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Version 8.23 of BallisticXLR Released

This new version has several tweaks to the primary and secondary functions tabs as well as bug fixes and formatting fixes. Now has wind values for 5-10-20mph and max ordinal update and an updated and more useful danger space calculation. The next version will see removal of Extended Data tab and a huge number of updates to the record keeping, graphing and statistics features. I’ll also be launching an entirely new version meant specifically for characterizing rifles.

Barrel Life: Estimating With Mathematics

People ask me probably 10 times a day, “How long will my barrel last?”. I hate that question. Makes me want to bash my head on a desk because they’re asking me to predict the future and counting on my answer being exactly correct. It can’t. I can get close though and so can you.

Tada: Below is the actual equation that I use (NOTE: I did not invent it and never claimed to have.) to give me an idea of my accurate barrel life. This is really meant to deal with match rifles where 1MOA groups are simply not going to cut it. This is also not something that’s necessarily scientifically precise so please see and use it for what it is, a mathematical MODEL. I’ve shot rifles well past the numbers given by the equation below but they all would soon enough tell me or had already started telling me they’re giving up the ghost.

Variable Definitions:
Powder Heat in KJ/kg (kilojoules per kilogram): H
Peak Pressure in PSI (subtract 10,000psi for Moly: M): P
Bore Capacity = (Bore Diameter^2 * 1000) / 2: B
Powder Charge Grains: C

The Formula for Non-Moly Loads:
((3800/H)^5)*3600/(C/B)^2)*55000/P

The Formula for Moly Loads:
((3800/H)^5)*3600/((C/B)^2)*55000/M

So let’s do the non-Moly math for my .243AI (which is a known barrel burner). Conventional wisdom is something around a 1300 round barrel life. Let’s see what our model says…

First replace all the variables with my numbers.
((3800/3990)^5)*3600/((45/29.52)^2*55000/55000

Next, just like we were taught in math class as kids, do the insides of the parenthesized sections:
(.95^5)*3600/(1.524)^2*55000/55000 = (.7737)*3600/(1.524)^2*55000/55000

Once all parenthesized sections have been reduced, run the equation left to right:
.7737 * 3600 / 1.524 ^2 * 55000 / 55000 = 1199 rounds of accurate bore life.

So yeah, the model is looking very accurate so far. What it cannot account for is how long of a delay between shots or how hot the barrel gets. One varies radically while the other is based on the thermodynamic properties of the barrel and the effect of environmental conditions. I’ve used this model for everything from .223rem, .308win, 7BR, 7MM Rem Mag, .243AI, 6.5BR, 6.5×55, .30-06 and .22LR with substantial success. It predicts a 1.5MM round life with a .22LR. Yeah, that’s about right.

This barrel life calculator is included in BallisticXLR and can even track against how many shots you’ve already fired and logged.

Get out and shoot!

RX17: Just A Few Quick Pictures

The man himself, TiborasaurusRex, teaching the fundamentals of long-range precision shooting on day 2.

Ivanpah Solar Thermal Power Facility from the air. Those shiny things are balls of incandescent air being super heated by focused solar energy at the tops of the boiler towers.

519″] The venue dedicated by Dubbya! Pretty cool.[/caption]

Yours truly hanging with Rex. This was truly an amazing class. Even the presenters learned new things. Hanging with Rex just made it so much cooler. What a great guy.

Me describing the intricacies of BallisticXLR. The students were fantastic. Great questions and good guys all around.

Rifle Stocks In Broad Strokes

Rifle stocks are seemingly simple things. They are the thing you bolt all the actual gun parts to and which keep you from holding all the actual rifle parts themselves. Why should they be so complicated then? Simple, they’re the interface between the oodles of different body shapes and the oodles of different gun shapes and even more oodles of use cases.

Trying to pair a stock with a rifle can’t be done without some vision of what the use case will be or you have a good chance of ending up with a rifle that doesn’t work well for its intended purpose. You can sort the things that matter into some very simple categories: Style/Form Factor, Materials, Bedding, Weight, Cost.

Figure 1 Conventional hunting rifle stock with short comb. Good for low mounted scopes with backup iron sights used from field positions. Short curved pistol grip works for everything from offhand to prone but can put a thumb in your nose on hard kicking rifles. Trigger actuation has a small amount of up in the angle that is not ideal for precision shooting. The definition of a general purpose stock.

Figure 1 Conventional hunting rifle stock with short comb. Good for low mounted scopes with backup iron sights used from field positions. Short curved pistol grip works for everything from offhand to prone but can put a thumb in your nose on hard kicking rifles. Trigger actuation has a small amount of up in the angle that is not ideal for precision shooting. The definition of a general purpose stock.

There are also some terms of stock construction that you should familiarize yourself with such as: comb, heel, toe, butt, grip, fore end, cast-off/on, length of pull, and pitch. We’ll ignore some of the fine detail here and cover the broad strokes. If you want to know more see some of the links, pictures and examples at the end of this article.

Styles are many and sometimes it’s less than obvious how to categorize what might be an element of one particular style or another versus what is simply variation within a style. The basic style of the stock needs to be able to position your eye in line with the sights in whatever position the gun is meant to be used in, provide a solid base to mount the action to and allow recoil to be absorbed. A stock that’s just right for shooting offhand while standing will be very differently shaped than one that’s meant to be shot from a bench rest or one that’s optimized for prone shooting.

Figure 2 Tactical rifle stock with no drop at comb & no raised cheek-piece and no drop at heel. Optimized for shooting through low mounted scope from a rested or prone position. Recoil is straight back. Comb is too high for low profile iron sights. Nearly vertical pistol grip puts trigger motion straight back. Narrow fore end and other weight considerations like barrel fluting make this a well laid out long range hunter.

Figure 2 Tactical rifle stock with no drop at comb & no raised cheek-piece and no drop at heel. Optimized for shooting through low mounted scope from a rested or prone position. Recoil is straight back. Comb is too high for low profile iron sights. Nearly vertical pistol grip puts trigger motion straight back. Narrow fore end and other weight considerations like barrel fluting make this a well laid out long range hunter.

In broad categories you have combinations of the following: wide fore end, narrow fore end, flat fore end, curved fore end, short fore end, long fore end, flat comb, raised comb, rollover comb, straight grip, curved grip, pistol grip, thumbhole grip, flat butt, curved butt, one-piece, two-piece, fixed butt, collapsible butt, folding butt, and probably 50 other things I’m leaving out.

The fore end is the part generally forward of the grip. I’ve always thought that there is missing terminology here because the part of the stock the action is supported by in my view should not be considered part of the fore end. The fore end to my mind should be everything that is forward of the receiver. This would rationalize the nomenclature in a way that stocks for lever action rifles which with very few exceptions don’t have any wood underneath the receiver and rifles with one-piece stocks. That’s an argument for another day.

Figure 3 Rimfire Metallic Silhouette rifle thumbhole stock with radical drop at heel and very high cheek piece for standing offhand shooting. This scope appears to be mounted too low to be used. This rifle would not be very usable for anyone who still has cheek bones. Nearly vertical pistol grip for straight back trigger pull.

Figure 3 Rimfire Metallic Silhouette rifle thumbhole stock with radical drop at heel and very high cheek piece for standing offhand shooting. This scope appears to be mounted too low to be used. This rifle would not be very usable for anyone who still has cheek bones. Nearly vertical pistol grip for straight back trigger pull.

Fore ends that are slender and curved on the bottom are generally more comfortable to shoot off-hand quickly. The curved profile fits the hand nicely. A flat fore end is optimal for shooting from some sort of supporting structure or device like sand bags or a bipod. Most shooters will find any corners to be less than comfortable for offhand shooting. There are notable exceptions to this rule in sports like metallic silhouette which is shot standing off-hand unsupported. Many shooters in that sport opt for a hold on the rifle that places the fore end on the finger tips with the tip of the thumb supporting the rifle closer to the magazine or trigger guard. While the flat fore-end works there, the shooters are taking a good bit of time for each shot. Hunters taking much quicker shots on average would not generally adopt such a stance or hold. A flat fore end allows for the rifle to rest evenly and flat on bags or rollers and for easy attachment of attachment systems like Anschutz rails and Picatinny rails to which gobs of nifty gadgets can be mounted.

The grip is the part your trigger hand holds. Grips vary from proceeding nearly straight back from the trigger guard to the comb (where your cheek goes) all the way to completely vertical and may or may not be part of the actual butt stock. Modern Sporting Rifles like AR/AK/FAL pattern rifles and their various kin tend toward a separate pistol grip. Most conventional bolt action hunting rifles have a pistol grip that’s part of the main stock and which curves gently downward and rearward blending into the butt section. Lever guns like the Winchester 1894 and some versions of the Marlin 336 tend toward straight non-curved grip sections that transition abruptly into the butt section. Generally target rifles with grips very near to vertical have some benefits in ergonomics as it allows the pull on the trigger to be more purely straight back. What is a benefit on the target range isn’t likely to be the case in the wild lands on a hunt where you need more flexibility and a more general purpose pistol grip profile like the common curved or straight forms are appropriate.

Figure 4 Hunting rifle with Mannlicher style stock and no drop at comb. For use iron sights. Could work with a scope but a proper cheek weld would be difficult or impossible. Long curved pistol grip has more upward pressure exerted on the trigger than is ideal for precision shooting.

Figure 4 Hunting rifle with Mannlicher style stock and no drop at comb. For use iron sights. Could work with a scope but a proper cheek weld would be difficult or impossible. Long curved pistol grip has more upward pressure exerted on the trigger than is ideal for precision shooting.

Now comes the butt section. There are a lot of parts here as most of the way a stock lays out is defined by various parts of the geometry of the butt section. The butt itself as a bit of nomenclature is both the very rear section that contact your shoulder and the stuff behind the grip. This is another area where I think we’re missing useful additional terminology but I’ll continue to avoid that discussion for now.

In the butt section will be the comb. As mentioned before that’s the bit that your cheek rests on. Its height is critical to aligning your eye with the sights in the vertical plane. If you’re not able to rest your cheek on the comb and see your sights then you need to raise or lower either the sights or the comb until you can for both your comfort and for the best results in your shooting. A very low comb like on a Winchester 1894 is great for use with iron sights but horrible for use with a scope unless you add a cheek piece that raises your head up high enough to see through the scope. A very high cheek piece that gets your head up high enough for a scope with a large objective bell will likely prevent the use of low mounted iron sights.

Figure 5 XLR Industries aluminum chassis stock. Recoil is straight back and stock is fully adjustable to get your eye where it needs to be. Pistol grip helps trigger pull go straight back while pistol grip angle is very comfortable.

Figure 5 XLR Industries aluminum chassis stock. Recoil is straight back and stock is fully adjustable to get your eye where it needs to be. Pistol grip helps trigger pull go straight back while pistol grip angle is very comfortable.

At the very back of the butt there are 2 positions that determine a lot of the overall geometry of the rifle. That is the heel and toe. The heel is the point at the uppermost, rearmost part of the butt. The toe is the bottom most, rear most point. The angle of those two points relative to an imaginary line drawn from the heel to the tip of the fore end determines the pitch, or up/down angle of the stock. The distance vertically from the heel to the top of the comb is the drop at comb.

Figure 6 Injection molded polymer Choate Varmint stock w/ internal aluminum bedding block. Low-ish mounted scopes work best due to low comb height. Pistol grip brings trigger pull straight back but is very nearly truly vertical which can be uncomfortable. Drop at heel of around an inch brings some muzzle rise when shooting on the bench.

Figure 6 Injection molded polymer Choate Varmint stock w/ internal aluminum bedding block. Low-ish mounted scopes work best due to low comb height. Pistol grip brings trigger pull straight back but is very nearly truly vertical which can be uncomfortable. Drop at heel of around an inch brings some muzzle rise when shooting on the bench.

A large drop at comb helps raise the action of the rifle relative to the butt. This is handy for shooting from the standing position as it helps keep your head and neck straight up and down which helps with your inner ear working with your brain to sense what level is so as to not cant the rifle. Any drop at comb will increase the uncomfortable perceived effects of recoil along with making it harder to recover from recoil. The M16 stock and most lever gun stocks come straight back from the axis of the bore to the shoulder providing a very straight path for recoil forces to travel down. That’s fine for a light recoiling gun but might not be so great for a hard kicking rifle. Just like with a pistol, raising the bore line above the comb line will cause more muzzle rise to be experienced. Just like with a single action revolver, muzzle rise takes energy to happen and allowing it to happen can lessen perceived recoil on the shoulder.

The drop at heel versus drop at comb determines the actual distance covered by the butt plate/recoil pad/butt. Too small a difference between the drop and heel and drop at comb will make for a sharp feel to the butt under recoil.

Figure 7 Winchester 1886 with radical cast-on (pushes action toward the chest) for a shooter with cross dominant vision. Also called a “cripple stock”. Very rare in modern times.

Figure 7 Winchester 1886 with radical cast-on (pushes action toward the chest) for a shooter with cross dominant vision. Also called a “cripple stock”. Very rare in modern times.

The cheek piece may or may not be of the Monte Carlo rollover style. A Monte Carlo cheek piece can add cast off by pushing the butt of the rifle a bit to the right without having to cut the whole stock with the cast off built in. The stock can also be cut with that cast off/on built in to the whole butt and pistol grip sections. Cast off moves the receiver toward the shoulder. Cast on moves it towards the chest. High end adjustable stocks sometimes have adjustments for cast but it’s not super common nowadays.

Finally in the geometry area we have length of pull which is the distance from the middle rear of the butt plate to the trigger. The length of pull is not determined by any single rule of thumb but has a lot to do with shooting style. If you use the old stand-by rule of the distance of your forearm from bicep to bent trigger finger you may find that on heavy recoiling rifles that your thumb and nose get brought together without it having been planned beforehand. Also if a shooter tends to crawl their head forward on the stock they may have an unplanned meeting between their head and the ocular bell of their scope.

Figure 8 David Tubb's competition rifle with radically positioned scope for chin-over-comb hold.

Figure 8 David Tubb’s competition rifle with radically positioned scope for chin-over-comb hold.

In an ideal world, where recoil management is concerned, your rifle bore axis will be in a straight line to just below the heel of the stock. Having the bore and the heel aligned in a straight line helps to bring recoil energy straight back so the rifle returns straight forward. This allows hugely faster follow-up shots and; more usefully, allows the shooter to much more easily spot their own impact. This is because muzzle rise is mitigated thanks to a bit of physics. Since physics is both boring and heavy on math I’ll skip the gory details.

Some stocks are designed with recoil mitigation in mind. Others like those popular in metallic silhouette actually substantially accentuate muzzle rise as a sacrifice to other matters, in this case avoiding canting the rifle. Standing straight up without craning your neck is better for balance thanks to the way the inner ear works. The accentuation of muzzle rise is not a problem in metallic silhouette for various reasons but it is for shooting from a supported position such as is common in long range hunting or banging at steel.

Figure 9 Butt stock geometry elements.

Figure 9 Butt stock geometry elements.

When shooting prone from a bipod, or off a backpack, or with the rifle laid across a log, or rock or mound of dirt you’re going to want to be trying to get as directly and straight behind the rifle as possible, as low as possible and to achieve a natural point of aim. So done, upon firing the straight back recoil path of a rifle in a stock with little or no drop at the heel lets the energy travel right into the shoulder pocket and for the shoulder to return to its former position in a straight line.

With the bore slightly below the level of the heel of the stock such as we see in the AR-10 and AR-15 platforms (and let’s not forget about the Nemo Arms Omen line of magnum AR platform rifles) recoil energy is just about as straight back as it could be and spotting your own shot and delivering fast follow-up shots gets surprisingly easy.

Figure 10 Anschutz Olympic rifle with fully adjustable stock. Recoil control isn’t given much thought on this .22lr. This stock is optimized for offhand unsupported accuracy.

Figure 10 Anschutz Olympic rifle with fully adjustable stock. Recoil control isn’t given much thought on this .22lr. This stock is optimized for offhand unsupported accuracy.

Suffice it to say, if you can see that the elk you just drilled was hit a bit high in the chest because you see the bullet hit you’re more prepared and able to decide to deliver the second shot quickly and minimize suffering on the part of the animal. Conversely, if you hit it square in the pump and it takes to running off you’ll be much less likely to unnecessarily destroy any more meat if you know it’s going to be quickly lethal and you know you shattered the shoulder. Everyone loves as few shots being loosed as possible in the wild lands during hunting season. It’s better for everyone’s hunt to keep the noise down.

For steel shooters being able to spot exactly where your shot landed and even watch it fly through the air is always helpful and entertaining. Adjusting your hold becomes easy when you know for sure how far off the last shot was. In games like PRS winning matches versus coming in second is frequently a matter of a single point. You often have more than 1 shot at a target but you don’t likely get to have a spotter working for you (any spotter will be scoring, not so much helping). Being able to see your impacts whether on steel or off steel means faster follow-ups and higher 2nd round hit probabilities.

Figure 11 Traditional single shot Swiss Shuetzen rifle for standing position shooting. An example of extremes in buttstock design. Lots of muzzle rise comes from this layout.

Figure 11 Traditional single shot Swiss Shuetzen rifle for standing position shooting. An example of extremes in buttstock design. Lots of muzzle rise comes from this layout.

Materials selection is another big area full of complexities. The bulk of materials used in factory rifle stocks are good and strong and stable though some have seriously sub-par options available. A good stock shouldn’t have any flex in it. Flex is the enemy of consistency. High end stocks are very rigid and often, though not always, very light. They get there with exotic materials and rather expensive manufacturing processes. There’s a reason they cost that much after all.

The lower end of package rifles and bargain line rifles will commonly come with an injection molded plastic stock that’s got a lot of flex in it. If you can avoid or replace those. The fore end on these will often flex enough to contact the barrel which is not normally good for accuracy or consistency. On the upside such stocks usually have some sort of metal pillars serving as bedding. On the downside, they’re intended more as ferules than as bedding blocks and serve as such. Wood stocks of the traditional regular wood variety can subtly change dimension due to changes in environmental conditions. There are good solutions for bedding and finishing that trim that problem to a manageable level. Aluminum stocks are generally impervious to flex. As well, every fiberglass or kevlar stock I’ve ever seen has been similarly rigid to aluminum. In the recent decades laminated wood stocks have become common and popular. They offer the visual appeal of wood with a lot more resistance to swelling or contracting due to moisture and great rigidity. Bedding of a laminated stock should be given the same attention you’d give any traditional wood stock, or any other stock for that matter.

 Figure 12 Big Bore Double Rifle. The recoil tolerability limits of the human body made manifest in wood and steel.


Figure 12 Big Bore Double Rifle. The recoil tolerability limits of the human body made manifest in wood and steel.

Bedding is a long and fraught subject and many times methods are combined. You can pillar bed, which uses pegs of metal usually which the receiver rests on and which the bolts that hold it down go through and press against. These are fixed into the stock in a variety of methods, most usually a snug hole and some adhesive/epoxy. You can epoxy bed which is to use a great gooey gob of epoxy to form the spot the action will rest in. This nets a perfect fit between the action and the bedding surface. You can also so a skim bed which is to use a much thinner layer of epoxy to do the same thing. Depends on the inlet done to your stock as to which is appropriate for you. I do an epoxy skim bed on my aluminum chassis stocks which have an aluminum bedding block machined into them and on my fiberglass stocks and on my wood stocks. Some aftermarket fiberglass stocks and even some wood stocks come with an aluminum bedding block actually fitted into them. These are great for maintaining a more conventional look but having all the greatness that can come from an aluminum bedding block. Whatever bedding system you go with, take the time and effort and cost to do it or have it done properly.

Weight is a function of material and mass. You want to have your rifle balanced correctly which means that the lightest stock material may not actually suit your combo or needs. Where weight limits aren’t a factor things like heavy metal (mercury/tungsten/lead) stock inserts can help to fix the balance. Composite stocks like carbon fibre/kevlar/fibreglass often need some weight added to the back to bring the rifle into balance. Wood and laminate stocks tend to balance pretty well without special measures. Aluminum stocks tend to shift the weight rearward. The chronicler is of the opinion that the best balance is to have the balance point directly under the closed bolt head.

Figure 13 Steyr HS-50 Anti-Materiel Sniper Rifle. Straight back recoil path for the hard kicking .50BMG. Even with a big brake it’s a big kick.

Figure 13 Steyr HS-50 Anti-Materiel Sniper Rifle. Straight back recoil path for the hard kicking .50BMG. Even with a big brake it’s a big kick.

Cost. Ahh yes, the thing that causes otherwise rational people to buy garbage. If you want a simply functional stock you can get one cheap but, don’t expect it to do much but hold the rifle away from your skin. If you want a really good stock it’s going to cost you. You can go anywhere from buying a replacement “tupperware” injection molded stock used on E-Bay for nearly free to spending many thousands for some of the fancier and bespoke stocks. As you put cool features like aluminum bedding blocks or glass and pillar bedding the price can soar. Super awesome finishes of hand rubbed boiled linseed oil are going to have heart stopping prices tied to them.

When you go to put a rifle together or just to buy one off the rack, be sure that you’re thinking about what you’ll do with the rifle and pick the stock that best suits that use case. You’ll be glad you did and you’ll have more fun in the field.

Links:
https://en.wikipedia.org/wiki/Stock_(firearms)
http://www.chuckhawks.com/rifle_stock.htm
http://home.insightbb.com/~bspen/fit.html
https://www.icslearn.ca/~/media/files/pdf/samplelessons/025-gunsmith-career-diploma.pdf?la=en

Midway Rifle Case and Shooting Mat Backpack

These are well built but not built like tanks. Zippers are reasonably rugged and come with string pulls. There’s oodles of MOLLE webbing and the pockets are generously sized. Backpack straps are very comfortable with no bits of metal digging in anywhere. The rifle case shoulder strap is similarly comfortable. All in all these have been great purchases and have done more than 100 matches as well as additional recreational shooting trips. In all of that time the only damage has been one snag on a barbed wire fence. The hole that made hasn’t grown in over a year. Midway really made a quality product with these. They’re a little heavy for what they are but that weight comes with durability and you’re just not going to get durability any other way no matter what you spend… even if you made your rifle case out of actual money.

On to the pics.

Midway Rifle Case (front) and Shooting Mat/Backpack (rear).

Midway Rifle Case (front) and Shooting Mat/Backpack (rear).

midway_drag_bag_back

Rear view.

midway_drag_bag_open

Open View

midway_drag_bag_front

Front View.

Coach and Meccastreisand with their rifles. TheDiscoTripper dutifully taking pics. Teamwork starts with the right team.

Coach and Meccastreisand with their rifles. TheDiscoTripper dutifully taking pics. Teamwork starts with the right team.

IMG_4126

Coach and Meccastreisand catching some relax juice while waiting for our relay to start.

Doing that match shooting thing.

Doing that match shooting thing. The big guy is one of my preferred squad members.

This guy gets a Tactical Barbie award for sure. He's a great chap and a fantastic shot in reality and I like ribbing him.

This guy gets a Tactical Barbie award for sure. Wearing a shemaugh. He’s actually a great chap and a fantastic shot in reality and I like ribbing him for the neckerchief.

Custom Mossberg MVP in .223 (r) and custom Savage 110 in 6XC

Custom Mossberg MVP in .223 (r) and custom Savage 110 in 6XC

And another of the guns. Shooting mat has a lot of room.

And another of the guns. Shooting mat has a lot of room.

Making DOPE With BallisticPRS

I was recently asked to create a Density Altitude version of BallisticXLR for those that like DA over absolute air density. Ok, fine. Done. It took quite a number of hours to port it over but it’s there now and it works. This new system is meant for shooters that need extremely rapid ballistics data that is easy to read under time pressure and that can deal with atmospheric changes extremely rapidly.

And here it is!

ballisticprs

The inputs page is a very close match to the original BallisticXLR inputs page but unlike BallisticXLR does not require any atmospheric data inputs. BallisticPRS also differs from BallisticXLR in that it does not have the Primary or Secondary Functions tabs and a number of other tabs that are not relevant for DA applications. It does come with the reloading cost calculator, projectile database, reticle subtend tab, and sniper range cards.

BallisticPRS is meant for the experienced shooter while still being easy enough to use that beginners will not find it stammeringly confusing. As seen below the data tables are noted in meters or yards with data in 10yrd/m increments from 100 to 2490. Data for Drop, Wind, Movers, H-Cor, V-Cor and Spin are listed in a single row making for very fast info uptake.

ballisticPRS1

There’s an included DA tab (which is experimental) that will allow the user to identify a correct DA with a non-standard temperature and a pressure altitude reading. This handy feature will assist the shooter as temperatures change throughout the day in their FFP.

ballisticprs

This latest product is free for download and; just like with BallisticXLR, I provide free email based support. Just like BallisticXLR, BallisticPRS requires genuine Microsoft Excel for correct function. I’ll be adding a new BADEDS and B-FEDS kit with the DA tables shortly. Because of the much larger page count these kits will be modestly more expensive.

I’m very excited about this new product and I think you will be too!

P.S. – Being that it’s Memorial Day as I post this, I thought I’d leave this here. The price of freedom for some is said to be the blood of patriots and tyrants. It could also be termed the blood of our children and our parents. Dead and living soldiers bought this day off for us.
noname

All About Rifle Scope Reticles

A reticle is simply a set of markings inside an optical device for use in measuring, pointing, aiming, etc… My 8″ Newtonian telescope comes with an eyepiece that you can use for aligning the telescope with the Earth properly so its drive motor programming can drive it to pre-determined stars and planets automatically. Inside that eyepiece is a reticle of sorts, there are several stars and constellations. You adjust the scope to place the legs facing north and those reticle elements on the actual image of the sky. Once the reticle and the real stars are aligned, the telescope is aligned. Nifty huh?

Reticles_assortment

In weapon scopes we have quite a lot of variety. Part of that comes from the variety of weapon types and part comes from the variety of ways those weapons may be utilized. There is such a thing as a general purpose rifle scope which would tend to come with a general purpose reticle. Anything that’s meant to be general purpose can be pressed into service for most needs but it’s not going to be optimal for probably any of them. This means it’s important to select your reticle with the same pickiness that you’d select your rifle, your ammo or your boots. Make sure it’s up to the task.

Reticle designs have exploded in number and manufacture method in recent years. As people have crafted solutions to new and old problems, the number of reticles and their specialization has dramatically increased. What many will find surprising is how astonishingly old most of the technology used today is. There is some exciting technology that’s been developed in more recent years but the fundamental method for creating a reticle hasn’t changed in centuries.

Reticle Manufacture Methods:

Wire/Hair:
wire_reticle
In the oldest days you may have had a simple crosshair which would have literally been a pair of intersecting spiderwebs (which are astonishingly strong and flexible) or actual hairs (later wires) tied between posts inside the scope. Primitive and fragile though they are, they solve the first problem: The aim point. Now there is one instead of just a view of some section of the target with no identified center. Before long it was realized that there was a growing need for more sophisticated aiming points and for those points to be useful for intelligence gathering. Thankfully the technology to make such a thing had existed for a very long time already. One problem a wire crosshair will never experience is flecks of debris appearing to float on or around the reticle. That only happens with etched reticles because of gravity, which brings us to:

Etched:
etched_reticles
As early as the 1700’s crafty people were thinking of etching a reticle onto glass. This practice allows extreme flexibility in reticle design as floating elements can be very easily accommodated. This is the dominant system in top quality magnified rifle scopes today. Some have said that etched reticles are less durable than wire (Wikipedia). I would dispute the hell out of that. A genuine problem brought in by etching is that the etched bit will disperse some light thereby lessening transmission marginally more than a wire reticle. Etched reticles are more expensive and difficult to manufacture and they are going to be able to rotate which is annoying and unhelpful and requires advanced adhesive technology or mechanical impingement systems. Where wire hairs may break under the stress of a big shock (like dropping the rifle), etched reticles may also rotate after a big shock. Etched reticles also exist on their own hunk of glass. Glass isn’t going to transmit 100% of the light so you will lose some.

Collimated/Reflected/Reflex:
Reflex_Sight
Reflected reticles aren’t inline with the incoming light like wire and etched reticles. Reflected (called Reflex) reticles are literally projected onto a lens at an angle and the image reflected back to the shooter superimposed and collimated with the target image. The AimPoint CompM2 uses this system as do many red dot sights. The need to project light onto the lens through which the primary image is coming means that there’s a sort of minimum line width and brightness which is pretty beefy when compared to a wire or etched reticle. There’s also the potential problem of bloom. Bloom is not entirely common anymore but it consists of a scatter effect like looking into bright lights at night. Reflex reticles which are high quality will not exhibit bloom. Because there are no physical parts of the reticle you can get very creative about reticle design just like with etched reticles. Battery life with these can be ridiculously long (on the order of years of power-on running) because of the low power output needs of the illuminator. The Burris FastFire III uses this system.

Holographic:
holographicreticle
Holographic reticles are much like Reflex reticles in that they use light to bring the reticle to life. Unlike Reflex sights that project light onto an interior surface to form the reticle, a holographic sight uses an etching on a lens element in the primary optical path which is illuminated by collimated laser diode. It’s a bit like a mixture of an etched reticle with an illuminated/reflex reticle. Similar to Reflex sights, holographic sights can suffer from bloom. Battery life with these can be poor compared to a Reflex sight due to increased power needs to illuminate the hologram. Eotech 512.A65’s use this system.

Reticle Focal Plane:

front-and-second-focal-planes-of-the-rifle-scope

Focal plane is pretty simple to contemplate. First focal plane refers to the placement of the reticle element literally near the front of the scopes internals with the result of the reticle being the same angular size relative to the target or object being viewed. If I were to wear a t-shirt with a big X on it and walk towards you, you’d see the X get bigger and bigger because it’s attached to me. Second focal plane refers to the reticle always staying the same size. This can be modeled by placing a big wire X a few feet in front of you and having the target move toward you but not having the X move. The X would appear to stay the same size while the targets apparent size would continuously change. Each has its place. This only matters with variable magnification scopes. With a fixed power scope, since magnification never changes, the actual location of the reticle becomes largely immaterial.

First Focal Plane:
First focal plane reticles are necessary if you want to use a reticle for estimating range to target and to be able to do so at any of the available magnification levels of your optic without having to take additional steps in the math or actions such as setting the magnification to a specific level. FFP reticles are wildly popular in the tactical/tacticool/sniper/long-range worlds where you’re shooting for hits rather than for X’s. FFP scopes will be more expensive than second focal plane if that’s the only difference between them. The reason is simple, another lens near the front of the scope. It’s a small and necessarily finely crafted lens with an exactingly precise reticle etched into it and it’s placed very far toward the front of the system of lenses by necessity. Small things that are super finely crafted and placed deep inside complicated mechanisms are expensive. That’s how things work. The lines inside the reticle on a FFP scope are at precise angular distances from each other and can be placed over other elements in the image to compare angular size. If you know the angular size and the actual size of the thing you’re looking at you can deduce how far away it is. When you increase magnification on an FFP scope the crosshair will appear to grow in direct proportion to the apparent size of the target. At low magnifications a FFP reticle may be little more useful than a standard Duplex. At high magnifications it may occlude quite a lot of the image of the target. That’s not going to be super helpful to people shooting for X’s but it is a very fast way to range and hold-off and allows the shooter to rapidly engage targets with lower magnification and to precisely compensate for wind, movement, etc… without having to fuddle with turrets.

SFP_FFP_images

Second Focal Plane:
Second focal plane reticles are desirable any time you want a fine reticle to stay fine as magnification changes. It might seem odd to some reading this, but sometimes folks do want that feature. Because the lens is placed closer to the rear of the scope and not deep inside its guts there’s typically a little more room for using a larger lens element, or even for just stringing a pair of wires across each other (some still do that). Because it’s SFP the lens element with the reticle can more durably be installed and it’s easier to fabricate, easier to install and cheaper because of that. Just because a scope is SFP doesn’t mean it’s not as good as a FFP scope. They have their purposes, each of them. Second focal plane scopes are extremely popular in target shooting applications where group size is measured and for hunting. If you’re shooting for X’s you’re going to be best served by a SFP scope.

Reticle Layout:

Fine, Duplex, Post, Mil-Dot, Circle, Target Dot, Christmas Tree, Hunter Ranging, SVD… Which one is right for you. You want the least complicated reticle that can do the job you need it to do. Having too much going on in the scope will absolutely slow the shooter down which will require more training to overcome. Below we’ll introduce some common reticles and some not so common ones and give a brief blurb about common uses for each. This is by no means going to be comprehensive because much like a screwdriver handle occasionally will become a hammer, a target scope sometimes will get used for hunting. Neither works great for off-book use cases but they can be made to work.

Fine:
finecrosshair
A fine crosshair is the simplest reticle that’s in common use. Two wires are crossed to form the X or T or whatever letter you wanna call it. They’re typically pretty fine and their width is controlled by using wider or narrower wire to make them. In low light situations these can be very difficult to use and if they’re the old school type that are actually made of hair or spiderweb or wire then breakage is a concern. Benchrest shooters, people shooting for X’s and those shooting for group size will quite often choose this layout along with extremely high magnification as it obscures the least possible amount of the target so they can see their bullet holes, even from a great distance and even with very small bullets.

Duplex:
duplex
Duplex reticles are a fine-ish crosshair in the center that grows to be quite wide nearer the edges. The transition is normally abrupt rather with a very short triangular taper. These are just about perfect for hunting non-dangerous big game with a rifle. Low light situations are helped by the wider lines and precision isn’t hampered because the crossing lines are still fine. The thicker lines guide your eye naturally to the center so they’ll much more easily pick up the fine hairs in low light. This is probably the most popular reticle in the USA and is used on the vast majority of hunting rifles that are equipped with a scope. Some companies have made FFP versions (the 30/30 reticle for example) but most are on SFP scopes.

German #3/Post:
german
Also called the German reticle provides an open field of view with minimal stuff going on and is ideal for hunting dangerous game and was heavily used in early eastern European sniping scopes. The thick center vertical post is quick to pick up even in low light. The pointed top of the post allows combat sniping precision without a temptation for the sniper to spend too much time refining their aim point. The thick horizontal bars at the edges help the sniper avoid canting the rifle. The reticle is simple to make and lacks ranging stadia. For German snipers in WWII this was very effective. When hunting dangerous game or hunting in a dangerous environment the lack of extraneous stadia makes for a very high level of situational awareness and increased speed of use. Things don’t always need to look fancy to be sophisticated. This forms the foundation of the much more sophisticated SVD type discussed further below.

Mil-Scale/Mil-Dot:
milscale
mildot
Scopes with reticles with miliradian subtends can be used very easily for range estimation and provide a brilliant method of fire correction. There are 2*Pi radians in a circle which isn’t helpful for most people. In the interests of not making you do math, suffice it to say that for 1 radian there are about 57degrees of arc. That’s a huge amount of arc so we cut it into 1000 little pieces which are very approximately .3 minutes of angle each (which works out to about .36 inches at 100yards). There are 60 minutes in each degree so we’re talking about a very fine set of intervals which allows very small differences in target size to be helpful in estimating target range which makes for great precision. Why not use minutes of angle? When using Mils/MRAD everything we do is in base10 and we tend to do it with metric measurements of the target and world which makes for easy math. Minutes of angle on the other hand uses base60 (thanks ancient fertile crescent residents for the hellish system of mathematics) and the SAE measurement system (feet/inches) is base12. Base60 and base12 are compatible in places (12*5=60 right) but they’re not easy to mix in your head and few of us have 12 fingers to count on to help. Scopes with their reticles in mil-scale and with mil-scale turrets make fire corrections ridiculously simple, especially if you use metric linear measurements for target size and range. With a scaled reticle like these and turrets in MRAD you can watch where your bullet landed, measure it in the reticle, adjust exactly that much up/down/left/right and fire. There’s no converting to or from minutes of angle and no guesswork. Scopes with mil-scale reticles are wildly popular in many forms of shooting including PRS, Long Range Tactical, 3-Gun, etc.. as well as with tactical/SWAT units of police departments and military snipers. If you need flexibility between being able to deliver slow precision fire and being able to deliver rapid and effective if slightly less precise fire (precision and speed are mutual enemies).

MOA-Scale:
moascale
This is more or less the same as a mil-scale but instead of using miliradians they will use minutes of angle or some fraction thereof. All the same basics in use case apply from mil-scale to moa-scale. There are reasons to use a MOA-scale reticle and it’s entirely probable that if you need one, you know it and know why. There is also a sub-type of MOA scale which is IPHY or inch per hundred hards. 1MOA is 1.05 (or 1.09 depending on how you measure) inches at 100 yards. Because different scope companies had different ideas of how to measure 1MOA some other companies decided to say the heck with it and adopted a system which is exactly 1 inch at 100yards. The math is much easier to do in your head without extraneous decimal places in the significant digits. While IPHY is by definition not MOA it’s very very similar. Both have smaller linear distances covered at any distance than MRAD with IPHY having the smallest subtended linear distance. The small value lends itself to a smaller click value and the ability to dial more precise adjustments. For target shooters an IPHY scale would probably make sense. For those that just can’t grok the metric system of linear measures, the MOA scale is probably up your alley (though you should really learn the metric system for your own benefit).

Circle/CQT/CQC:
circle-scale
These used to be nearly exclusive residents of the realm of shotgun scopes but someone figured out that they make brilliant combat reticles because they’re super fast and easy to use. Put your target in the circle and kill it. Simple. Now we’re starting to see really clever things like circle reticles being placed in the second focal plane and a secondary crosshair or scaled reticle being placed in the first focal plane in the same scope. This in theory enables the shooter to engage long range precision targets as well as deal with high intensity combat at conversational to hollerin’ distances. That combination is finding more and more appreciation within the 3-gun world as well but still has its home in more genuinely deadly use cases. This is a case of everything and the kitchen sink. It’s not going to be perfect for most anything except for giving someone in battle a leg up if they’re well trained with it.

Target Dot:
targetdot
This may consist of a simple dot in the center of the field of view but is more commonly combined with a fine crosshair. The dot may cover anything from 1/8moa to 3moa or more. These are popular with many sorts of target and varmint shooters. The tiny dot moving over your target gives an easy to see and fast to pick up signal to the brain to pull the trigger while the fine crosshairs give an aid in not canting the rifle. In metallic silhouette competition these are wildly popular especially in very high magnification scopes. Varmint hunters seem to really like the hair:dot system as well as many target disciplines which go by X count or group size or both.

Christmas Tree:
christmastree
These are a more recent development which has gained popularity across the shooting sports and military world. These consist normally of a first focal plane mil-scale cross-hair reticle which is then decorated with elevation and windage stadia in something of a pyramid below the primary horizontal cross-hair. While pretty busy in the eye these reticles allow for the user to hold off from the center of the target to account for range, wind and movement without having to twist the turrets. That makes these a potentially incredibly fast scope to use particularly on ultra challenging PRS courses because you can transition from close targets to far targets without having to tinker with your scope. Horus has come up with a pretty big selection of this type of reticle. There are also many proprietary reticles of this type. When selecting this type of scope reticle for use it’s important to know about how much training you’ll need to do to be proficient with it as well as picking the exact design that well suits your needs. These make a pretty poor scope for shooting for groups or X’s in competition, they’re not ideal for most hunting situations either. They’re fantastic for speedy target acquisition and engagement in tactical and simulated tactical pursuits.

Ballistic Drop Compensating / Hunter Ranging:
bdc2
bdc
Ballistic Drop Compensating (BDC) reticles come with additional intersecting lines on the vertical post that correspond to various ranges based on your muzzle velocity and bullet choice. These are fine for short to intermediate ranges but rapidly lose veracity as range increases. Up to about 400 yards they’re great but after that actual ballistics should be referred to to assure a humane harvest of your target animal. Some of these reticles like the Bushnell 30/30 (which appears to be a regular duplex until you find out it’s first focal plane) are meant specifically for deer hunters so they can quickly range their target. There’s a long running debate in some circles about whether including ranging and distance compensation features in a hunting scope is really worthwhile or if it’d be better to either not have them or to get a scope with those features fully implemented, like a mil-scale scope. While mil-scale reticles and MOA scale reticles have their secondary line intersections at precisely equal angular distances, BDC type reticles almost uniformly do not place the secondary aim points at even intervals. This makes them more difficult to train on, memorize and apply to new situations and environments. BDC reticles are generally limited to .5km distances and should be as things like air temperature and barometric pressure really start to matter around there. For people with a small area of operations and a mission profile that allows for shots being limited to 500m or under these are pretty good options for shooting at meat. For target use, they’re generally inappropriate but like a screwdriver handle can become a hammer, a BDC scope can be pressed into service as a target scope with some performance consequences.

SVD:
svd
A fairly unique reticle that’s more or less limited to eastern bloc Soviet aligned countries’ sniper rifles. This reticle is actually a series of them. There’s a ranging box meant for use with human and human sized targets to provide rapid range estimation. There are chevrons which provide hold-overs and there is a horizontal mil-scale for hold-offs and whatever else you find you need them for. While being possibly the foundation of the ideal universal reticle the SVD reticle just hasn’t caught on with western shooters like those above have. It’s not meant for precision but instead; and in a very Soviet way, for combat. It’s meant to allow poorly trained designated marksman to put reasonably accurate fire against human and materiel targets with the least amount of hassle (training) possible. Where western armies developed doctrine that used snipers as force multipliers and intelligence gathering resources, the Soviets were less interested in having front line troops reporting intel back up and seemed happy to have them just go ahead and engage the enemy. Again, pretty standard Soviet thinking. They did understand ever since WWII that effective use of large numbers of designated marksman does sap the heck out of your enemies will to fight and their ability to freely move around and this sort of reticle is ideal for that. It’s not very good at all as a target reticle for any pursuit where you’re counting group size or X’s but like everything, can be pressed into service with consequences.

Choosing the Right Reticle for You:

First: remember that a fine crosshair is about the standard minimum. Every reticle feature or element after that that you add in after that will either increase the cost of your final product, orient your scope for use in one pursuit or another or force the manufacturer to reduce its quality to maintain profitability. So, keep it as simple as you can and don’t buy what you won’t use. We all want the whizz-bang-est scope in the world. It’s nice to own the best when the best is measured by its cost. In this case though the best is that which accomplishes the mission without costing you anything extra.

While you’re shopping around decide if you need first or second focal plane first. This will be the thing that limits your available selection the most. If you shoot competitions at unknown ranges then first focal plane is almost dictated if you want to not have to lug around a laser rangefinder. If you shoot in competitions where group size is important then you’ll probably be best served by second focal plane. That’s a good rule of thumb but not gospel so think about it and see what others are using before you make a purchase. Other competitors are going to on average have a set of features in common and are your best source of comparative shopping especially since they’ll usually be pretty generous about letting your look through and compare different brands and models. Hunting at close to intermediate (<500yrds) ranges won’t make any dictates about FFP vs. SFP but anything further you’ll want to consider the environment (vegetation, terrain, species) carefully as well as lighting. Fine crosshairs in low light can be difficult to use. Broad crosshairs against a small target are just as hard to use.

After you’ve figured out which focal plane you want the reticle in and what purpose you’re putting this gun to we can start figuring out if you need ranging capability and from there if you need advanced features like hold-overs and hold-offs and if they need to be in even intervals or not. If you don’t need ranging capability, don’t get it. It’s just a distraction in the image if you’re not using it. If you don’t need BDC, don’t get it. If you need a target dot, get one. Below is a list of some of the reticles of my scopes and what guns they’re on and some of my reasons for choosing them. These are representative of the world at large in most cases and will hopefully provide some context.

Woods Big Game Hunting Rifle, .30-06: <1960 Weaver K3 3x fine crosshair.
I use this for hunting in dense woods for deer, elk, bear and hog. Low magnification and a fine crosshair make for a rifle easy to use in bright light but not so much in low light. I walk hunt when I hunt the woods so I don’t spend much time in low light.

High Power Metallic Silhouette Match Rifle, 7mm BR: Weaver T24 24x44mm AO fine crosshair & 1/8MOA dot.
Super high magnification (24x), fixed power and adjustable objective with target turrets. The thin crosshair helps me avoid canting the rifle. The target dot makes for instinctive trigger pulling when the dot covers some section of the metal target. Silhouette competition is done standing up without shooting aids like glove/jacket/sling and we have to knock the target over so a hit anywhere on it is all we really care about. Super high magnification helps me keep only 1 target in the scope at a time. Lots of downsides makes this a bad choice for a beginner and a catastrophic choice for things like deer hunting in the woods. This is not for everyone but is popular in target sports. They’re super popular with long range varmint hunters as well.

Long Range Precision Match Rifle, .223rem: US Optics ST-10 TPAL MPR reticle.
This rifle is used from 200-1000m to engage metal gongs at known distances under time pressure. The MPR reticle has extreme flexibility in the reticle without getting to be a Christmas Tree. There are subtends in there that aren’t actually listed, they’re implied, and so this reticle takes a bit more training than a simple mil-dot system. Fixed 10x magnification is easy to use when scanning along a ridge line for concealed targets. I have also used a 16×42 on this rifle and found that that was often too much magnification when you’re moving from target to target.

Long Range Precision Match Rifle, .308Win: US Optics ER-25 5-25x58mm MPR reticle.
This is the big brother to my .223 match gun. If winds are too heavy for .223 I use this rifle. Having the same reticle as my ST-10 equipped .223 rifle means I have less to train for. The ER-25 is a 5-25x58mm while the ST-10 is a 10x37mm so the ER-25 is a FFP which is an irrelevance for the ST-10 since it’s a fixed magnification scope. Being able to drop the magnification on the ER-25 to 5x makes targets in the distance easier to find (greater field of view) and then you can just zoom in to 20-25x. 25x is too much magnification for most things so it rarely sees full magnification. This scope is best left to tactical and tacticool sorts of pursuits. This scope occasionally will see my big 7mag for shooting up to a mile against 2MOA steel gong targets but that’s mostly because it has the adjustment range and the magnification, not because it has the perfect reticle for that.

Plains Deer Rifle, 7mm Rem Mag: Vintage 3-9x37mm 30/30 Duplex FFP.
This rifle is explicitly for shooting at deer in open grasslands. Shots can be from 10yrds to 600yrds. The 30/30 reticle is a standard duplex reticle in the first focal plane. It’s meant to match a 30 inch width regardless of magnification which is about the same size that an adult deer is long from neck to butt. You can tell by what portion of the reticle is taken up by a deer about how far that deer is from you. It’s handy and light and gives a feature I find useful while having snag free low capped turrets, fixed parallax and an uncomplicated reticle. Uncomplicated scope, uncomplicated rifle, uncomplicated reticle.

Alpine Big Game Hunting Rifle, 7mm Rem Mag: Leupold VX2 3-9x33mm Duplex SFP.
This rifle is explicitly for shooting at deer in the California hills. Shots can be from 10feet to 500yrds. The duplex reticle is in the second focal plane. It’s just a basic rifle scope on a basic rifle. I find it useful to have snag free low capped turrets, fixed parallax and an uncomplicated reticle. This rifle gets walked over rocky terrain in high mountains so it needs rugged and simple with a crosshair that works high and low light and doesn’t needlessly obscure the image.

 

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