Barrel Life, Accuracy and Velocity – Columbia River Arms Wins!

I’m running a .243AI set up by Columbia River Arms (formerly Black Hole Weaponry) about a year ago. It’s a pre-chambered drop-in with a pretty tightly necked chamber set up by CRA. I’ve got it set at zero head space so between that and the Ackley Improved case there’s zero brass growth after 4-5 firings.
It’s got just a touch over 1000 rounds down the pipe and appears to be going strong. So far I’ve only had to push the bullet out .010 and add .1gn powder to keep everything tight to my original load spec. I don’t know what kind of life the pipe has left in it. I’m running 115gn 6mm DTAC bullets at 3200fps with a modest charge of very slow burning powder (RL-23). Pressures are pretty mellow but it’s, for sure, burning that powder all the way down the barrel. This is evidenced by the fact that there’s just the tiniest bit of flash in the first chamber of my brake that’s visible in low light conditions.
Corey testing out the CRA barreled Hot-Dog Gun at 900yrds.
In a more conventional barrel I’d guess I’ve have between 100 and 300 rounds more life before it’s just not match grade anymore (based on a 1200-1500rnd life expectancy) but I would also expect substantially more throat erosion than I’ve gotten to this point if that were the case. I started with uncoated 108ELD’s and quickly went to HBN (hexagonal boron nitride) coated 115DTAC’s. The rebated boat tail and pointed tip on the DTAC’s pulls the BC up to .620 which puts me up to 1mile of supersonic range. So far it’s been as far as 1500yrds and proven itself very capable.
Out of the gate I was getting 10 shot groups like those below (these are fireforming and load development groups, the first loads out of the barrel). After a little refinement they settled down to repeatable .5-.7MOA across 10 shots with single digit SD’s (5fps across over 100 rounds loaded in 3 sessions). The thing has since then been ridiculously consistent. Once I found an optic I could deal with in matches (I hated the turrets on Vortex Razor 2’s, U.S. Optics ER-25 was just too damned big, SWFA 16×42 was too much minimum magnification, etc… nitpicky stuff) in the form of the U.S. Optics SN3 3.8-22x58mm with a custom made PRS oriented reticle and 35mm main tube, I really started to have some fun with it including punishing the rifle with 10 shots strings in 90 seconds on hot days (hey, that’s the stage on the match). I wasn’t going to take it easy on this barrel.
I crossed the 1000 round mark in the summer of 2018 at a match and I’d thought the barrel might be toasted then due to some repeated and huge misses on otherwise simple shots. It was so convincing that I decided to not take the rifle with me to Africa on a hunting trip. Turns out it was just me. I clearly did something wrong to make those misses. I know that because I went out again this month to teach a long range precision rifle class and demonstrated most drills and techniques with my .243AI. It started out by making a .5″ 5 shot group @ 100 yards. At the end of the class it got to be time to see what I could do under some performance pressure so I got right down into the prone with my Columbia River Arms barreled Savage 10FPSR, dialed the parallax on my U.S. Optics SN3 3.8-22×58, extended the Accuracy Solutions BipodEXT, set the Accu-Tac SR-5 bipod to 45deg forward and slapped a 6″ 900 yard 5 shot group on the steel rapid fire in direction shifting 5-15mph winds while the student body looked on.
I’m using 45.6gn of powder now. It started at 45.5gn of Reloader 23 in a very tight chamber with Hornady brass. By the book one should expect to see 3000-3100fps with 44-45gn of powder in a 24-inch barrel with 100gn to 105gn bullets. I’m getting 3200fps with 115’s and only 45.6gn in a 26″ barrel. I’d expect to see 25fps or thereabouts per inch of barrel after 24″ but certainly not 50fps per inch from barrel length alone and not with a heavier longer bullet. I’m also not even remotely pushing this round. I can go another 3gn of powder before even starting to flatten primers but 3300fps only serves to damage steel targets and is technically against the rules. 3200fps is max so that’s what I’m running. I already damage quite a few targets at 3200fps anyway so I don’t need any help in that department.
Hot Dog Gun in .243AI. A Savage 10FPSR with bits from MDT, XLR, Magpul, BipodEXT, Accu-Tac, U.S. Optics, Seekins, Weaver, and JP Enterprises. Painted to look like a Dodger Dog. Go Dodgers!

Typically as I wear out a barrel I’ll see it shoot fine, fine, fine, start to open up, plateau, fine at plateau, open up more, open up more, open up more and it’s all downhill from there. After the plateau if it doesn’t quickly plateau again it’s getting there and it’s time to start planning my next pipe. I’ve already started planning my next pipe, a 6XC to match an identical one we’ll put on Coach’s gun. Nonetheless, this barrel is still good. Question is, for how long?

I know from prior experience that I get a little longer barrel life from the polygonal rifling that CRA uses. I’ve not burned out enough of their barrels to get a useful statistical value for how much longer but I can speculate based on the limited data I do have. Right now, given the throat wear and grouping we’re getting on Coach’s existing 6XC; which is at 1500 rounds so far, and the expected life of that Shilen barrel being around 2200-2300 rounds, I’m estimating; and trying to be extremely conservative in that estimation, that I’ll make it to 1800 rounds or further before this .243AI pipe is really done for match work. (See update below).

The difference between .243Win (right) and .243AI (left) is shoulder angle, body taper, performance, case life and barrel life. The loaded round has a 108gn ELD-M in it and 39.5gn of RL-23 for fireforming.

That’s almost 40% longer barrel life than I initially anticipated, if it gets there. We knew that the HBN coating on the bullets would help barrel life but probably only marginally so I’m confident it’ll get to 1500rds. We knew the CRA polygonal rifling means no sharp edges for the burning powder plasma to ablate would help too. We knew the Ackley shoulder angle would keep the flame vertex inside the case neck and that that would help too.

It’s just with all those things helping, we have no idea where this train is going to stop. If I go on throat erosion alone, calculating how far until the boat tail is up inside the case neck, then I’m looking at almost 3000 rounds of barrel life. That’d be 230% of anticipated barrel life and I just don’t see that as being realistic given the amount of powder being burned and the rapidity with which I shoot in matches. I’ll get that barrel pretty hot sometimes.

Shooting stage 6 at my monthly match with Hot Dog Gun in its current form. Targets are on the opposite hillside from 300-700yrds away.

I get higher velocities than one might expect from less powder than one might expect. I get longer barrel life than one would expect. I get amazingly accurate and consistent performance, moreso than one might expect (especially for a drop-in pre-fit). The thing turned out sub-MOA groups with fire forming loads. It did not like 55gn varmint bullets at all though. No surprise on an 8 twist. The chamber on it is very tight. It’s meant for someone who’s willing to turn necks if necessary (my inside neck diameter on a fired case is .2435). Thankfully I don’t have to neck turn. Lucky me, everything just fits perfectly. When I ordered it I specified that I would not be put off by a possible requirement to neck turn brass if that were what their reamer would require.

Much of this situation was and is by design. When I initially decided I wanted a fast 6mm I found what my options were and then picked a chamber that would maximize performance, brass life and throat life. I picked a powder that would give maximum velocities without pressures being tall or a lot of flash. I picked projectiles that had very high BC’s and would be routinely available in boxes of 500 (including a primary and backup bullet). I set up a load that performs identically with both bullets and shoots to the same point of aim, just in case I’m unable to re-up on one I can use my backup supply of the other.  I bought all of the brass, powder and primers I expected to ever use in this barrel ahead of time (8lbs of powder, looks like I might need another 8lbs). Everything about the gun except the optic I’d settle on was decided before the barrel even arrived. Best of all, the barrel was set up to CRA’s rigorous standards which means it was done perfectly and it was under $400.

Hot Dog Gun before it was even painted. Getting some early long range testing done. Both Vortex Razor 2’s are now replaced with U.S. Optics glass. I just like USO. What can I say, they work for me.

So why am I building a 6XC now? Well Coach and I shoot together. It’s best if we have one set of ballistics DOPE and shoot the exact same load through identical chambers. It’s actually best if we share a gun but I like mine and he likes his. We find that when we can use drop and wind corrections from each other that we win more matches. Duh. If I run a stage and miss 2 of 7 shots on wind, I can tell him what the adjustments would have been and what the wind was for those misses then he can adjust accordingly and pick up those points and vice versa. (Update: Coach has left the BallisticXLR team.)

So, I’ve got 2 new barrels on the way from CRA, 27″ 6mm 8-twist unprofiled blanks which we’ll have a local gunsmith chamber, thread and profile for us in 6XC with a .264 neck (CRA doesn’t have a 6XC reamer or I’d have them do it). We’ll set them up for zero head space to minimize brass growth and then we’ll use my new ExactShooting.com Custom Collection sizing die to perfectly set the head space and neck tension of our reloaded ammo. We’ll be as close to shooting the same rifle as two guys can possibly get. If you want faster velocities, longer barrel life and one heck of an accurate barrel, you could do a lot worse than to drop Columbia River Arms a line.

.243AI Dimensions

6XC Dimensions

 

UPDATE: November 2019

Hot Dog Gun’s barrel finally gave it up. Throat erosion made it to the point that ammo was longer than mag length and if I made the ammo fit in the mag then group sizes opened up to almost 2MOA with tons of flyer action. The final round count was 1800+. So I took that barrel off and had my gunsmith gauge it. He found that the bore was still .239 which is exactly what it was when it was brand new. So we’ve cut the chamber off and run my 6XC reamer into it as well as cutting the tenon for M26x1.5 to stuff into my new Howa 1500 receiver. It’s got a new crown as well. We’re going to shoot this rifle till it starts key-hole-ing. Right now I’m betting that I’ll get a full 2000 rounds from this barrel. Probably a little more as we’re using HBN coated bullets. Let’s see.

New Friends Are Only 8,078 or 19 Miles Away

I had to land for a four hour layover in Dubai during my recent flights to and from South Africa. On the way to SA as soon as we landed I went to the Duty Free which actually is the entire airport area near the boarding gates in Dubai Airport now. I needed cigarettes. Wasn’t going to buy them in California at 8 dollars a pack and I was told they were 2-3 dollars a pack in SA. I didn’t figure they’d have any of the rather rare smokes I like though so I checked around the Duty Free and found cartons of Djarum Black for $13.26US and immediately bought a carton and headed to the nearest smoking lounge.

After I’d finished my first smoke another guy, middle eastern looking, walked in and sat at the next seat over around the same ashtray as me. We exchanged greetings and queries of where you going, where you from and such. The were are you coming from question for both of us had the same answer, San Francisco Bay Area. Our destinations couldn’t be much different. He was going to Afghanistan and I to South Africa.

Whiskeys of Scotland in airport of Dubai. My budget almost vomited. There are $30,000 bottles in that case.

Turns out the guy worked with our boys in brown over there during the war’s heyday and had moved at the first opportunity to California where he loves the climate and culture and clean & safe everywhere sort of feeling. The last remnants of his family, I gather, are in Afghanistan taking care of the last of their property holdings.

We chatted for a long while about religion, politics, war and sports and found that despite our mutual distaste for each other’s system of beliefs that we were perfectly happy to be in each other’s company and to talk, entertain and educate each other. After a while both of us were hungry and we retired to the nearest place where one can get shawarma. Having never really had an authentic regional copy I asked if I should get the sandwich or Arabic version (a wrap lightly grilled). He suggested the Arabic version and so we ordered. The food place had nice seating but didn’t serve alcohol so we both had what they called tea though it was doped with sweetened condensed milk and cardamom so heavily that it really resembled the taste of horchata more than tea. I was unused to the flavors but tried to enjoy them without a preconception. The tea worked to soothe and really broke the shawarma flavor up. The shawarma was, according to my companion, terrible if edible. I thought it would be spicier but was otherwise getting the distinct sensation that a Greek had introduced them to the gyro but called it shawarma so they wouldn’t get offended at it not being a local delicacy.

Arabic style shawarma. Broiled thin sliced meat, flatbread, salad, wrapped & grilled.

In the end we ate till just before my boarding time and then I ran full out to my gate to make my flight. My companion, whose name is Ghani, turned out to live not 20 minutes from my house so we traded contact info and agreed that we’d try to find a decent shawarma and continue our conversation upon our respective returns to the States.

In almost every way, the pair is incompatible. Opposites in so many ways. The salve for that problem though was to simply leave aside distaste and to engage in open and honest conversation where we didn’t bog down in the rote definitions of words. We defined the words with contentious possible meanings ourselves and left the “well that’s not what I call that” over to one side. It really made the conversation entertaining and educational.

If countries, religions, political movements and most of all groups of people could accomplish what we did there would be no international conflicts and fewer conflicts within individual nations. Live and let live gets you only so far. Sometimes you really need to deliberately set aside distrust or dislike and simply coexist.

Hi Ghani! Be safe in your travels and let me know when you’re back in the States. This time the dinner is on me.

Africa and Back – A Brief On My Trip In Pics & Text

My recent trip to South Africa was partly to do a couple hunts and partly to see what the long range precision rifle scene there was all about and how it could be well served. What products and services were available, what are needed and what just won’t play there. They have their own competitive rifle sports that are very like some of ours but different enough to have special needs. They also have a budding long range precision scene in the more common American influenced sports like F-Class.

Along the way I met a huge number of people: Gunsmiths, Knifemakers, Suppressor Makers, Farmers, Competitive Shooters, Guides, Importers, Exporters, Collectors, Legendary Hunters & Soldiers and 3 of the toughest, most well behaved polite & intelligent teenagers it’s possible to raise in this world.

I took some time to teach a few basic ballistics classes for some friends and we even got down to doing some long range live fire work complete with challenging drills and tests of both bravado and ability. Shots under 500m were there but we focused on shots over 500m and I have to tell you, these guys in South Africa are not fooling around. They’re motivated, well educated and not afraid to spend money if it’s going to return results.

I learned not only what biltong is but how to make it and why it throws jerky straight into a cocked hat. I saw fully 15 species of antelope, along with warthogs, ostrich, cape buffalo, and more. I got to experience what it’s like to be an ethnic super-minority and a chance to learn a little Afrikaans.

Afrikaans is a lot like Dutch but to the ear it sounds like there’s a lot of Hebrew or Arabic language influence with some of the sounds. I found it greatly difficult to understand spoken Afrikaans with my hearing loss eliminating vast wadges of the audio inputs and lip reading it is right out, much like Hebrew and Arabic. I did manage to toss a bit of surprise around when I picked up a book about wildlife which was written in Afrikaans and I started translating it to English on the fly, out loud.

For those that don’t know, modern English decends from Old English with tons of Norse, Latin and French tossed in. This is why English seems to lack a coherent set of rules… there’s nothing but exceptions to the rules it might otherwise have because all the languages it’s based on have different rules. Old English itself is largely descended from Dutch, or a Dutch relative and a surprising number of the words they use are pronounced identically (cheese, bread, meat, beer, blue, etc…) but are spelled in a way that would make Chaucer giggle. Once you figure out how they use vowels and some odd uses of the letter “g” though translating the language to English is almost unnecessary as it’s so much the same as English and the rest you can get from context pretty well. For someone that truly sucks at languages, this was a nice experience.

If you’re thinking of a trip remember that you don’t have to know a lick of Afrikaans to get along. Everyone there, EVERYONE, speaks English pretty fluently if with various accents and sets of commonly used phraseology. All the signs are in English. The retail infrastructure is quite a lot like a mix of European and American. It lacks the number of big box stores and has oodles of smaller more specialized shops (though big box stores are there).

It’s almost like visiting San Diego in a lot of ways, especially in the visual appearance of the landscape. Apart from the racial makeup (who is in the minority) you’d have trouble figuring out you’re not in a city in the American southwest somewhere, other than all the cars are diesel powered and they drive on the other side of the road.

Also, for your first time especially if you’re an American: DO NOT RENT A CAR TO DRIVE THERE. You really need a primer trip where you get driven around first so you can see how the locals actually drive or you most definitely will find yourself in a surprising situation or two and may piss someone right off by trying to be safe instead of polite. If you’ve driven in India you’re probably not going to be surprised as much but otherwise, take the first one with a local driving you around.

PICTURE TIME!

Knife made for me by Danie Joubert.

My Eland.

.308 150gn Sierra Game Kings working springbok innards.

Draining blood and guts from my eland.

One of the two toughest little girls I’ve ever met.

My eland on the ground.

Tracking my eland as it walks off to die.

Rough country doesn’t mean you can’t prone out properly.

Filling my guide in on where the eland went to die.

Getting our stalk on.

Africa is as austere a place as it is beautiful.

The tall thin trees are actually aloe’s. 3m tall aloe. Just wow. Never knew they grew into trees!

Authentic South African Boer recipes. In Afrikaans of course.

A braai of livers, hearts and sausages. OMG that was good.

My springboks getting their cool down on.

That’s a happy hunter.

With a poker face carved in stone.

My trophy springbok.

My first springbok.

Egyptian geese.

Wildebeest

Bontebok

A landscape that says, “You’re totally alone here. Don’t get injured.”

Outline for a little classroom ballistics session.

It wasn’t a formal class, actually greatly condensed. Still, we wanted everything to look nice.

Sakkie and his bride. A more amazing pair of honest, hard working, kind and generous people I have not met. Only James Yeager comes close (if you haven’t met James, you don’t know him).

It’s winter in Africa. And quite cold and windy.

Landowner warthog trophy.

Landowner bushbuck & caracal trophies.

A caracal trophy.

Kudu trophies.

My impala ram.

My impala ewe.

The buckey (what South Africans call a pickup truck)

Jacques confirming zero.

Black giraffe not 100m from our accommodations.

Ostrich

Johannesburg, SA suburbs. They name restaurants very strangely there.

Teaching ballistics eventually leads to a range session.

Dubai looks cool from the air.

Russia looks greener than I ever imagined it.

Teaching a little ballistics to a few friends.

Cruising through acacia trees on dirt roads. Like being a kid again.

These guys are great people, great shots and great students.

A landscape you just can’t find anymore. Empty of apparent human activity.

BallisticXLR Version 9.3 LIVE! Half-Sheets, Full Sheets, Wrist Cards & Tacti-cool Colors

BallisticXLR, the single most awesome external ballistics application to grace the face of the Earth has just outdone itself. We’ve updated the color scheme to be a lot less less Rainbow Brite and lot more Terry Shappert (we love you Terry). No longer does it have the insanely over rainbow’y color scheme Rex insisted upon. It looks Tacti-cool as hell now and is a lot easier to read and is lower visibility so when you use it in the field, you won’t be as easily spotted by counter snipers, herds of marauding deer, overbearing British government agents or lawless tea importers.

Font sizing, page breaks, information flow, etc… all have been massively improved. I’ve shrunk the file size and made tens of thousands of formula calculations more precise and much faster to use electronically as well as off-line.

Peep delta and tell me how awesome I am. Or not.

Fix your computer.
New Wrist DOPE Card with improved BDC generator. Folds for 2-sided awesomeness. BDC is automatic and you can change the reticle on it very easily.
Fix your damned computer. Seriously.
100yrd/m increment half-sheet DOPE. More compact, removed unnecessary stuff like coriolis, toned the colors down to be easy to read but hard to spot by counter forces.
If you can't be bothered to fix your computer I'm not going to help you.
Page 1 tab 1 of 10yrd/m increment tables. Faster reading, no page flipping, easier to read fonts, low-vis tactical color scheme and made for 8.5×5.5 half-sheet use
I fixed your computer. It will never show images again.
Page 3 of 10yrd/m increment half-sheet table. Notice the color scheme, automatic color changing to tell you how far you are into your maximum effective range.
My grandma and your grandma sitting by the fire.
100m full sheet table. All the data, including coriolis, reference data, conversions and all the other stuff you need for a day of recreating or hard target interdiction.

Sniper Weapon Fire Control Error Budget Analysis

ARL-TR-2065 Sniper Weapon Fire Control Error Budget Analysis

Do you know what a standard deviation is? If not, start with the Wikipedia entry on that then come back. The document above is rife with terminology from statistics. If you don’t understand the really quite simple definitions though you’ll probably miss the point.

What the document above says in short is that, all else being equal, a cold-bore shot on an animate or static man sized target beyond 700 yards is more or less a pipe dream. In fact, a first round hit even by a highly qualified shooter beyond 400 yards on a man sized target starts to get to less than 99% certainty of impact of metal anywhere on meat.

BipodeXt by Accuracy Solutions – It’s Almost Magic

It’s simple: In normal form a bipod will be about 1/2 way between the muzzle and the butt of the rifle. By adding a BipodeXt from Accuracy Solutions you’ll move your bipod forward by from several inches to a couple feet. This takes the pivoting load off of the fulcrum and puts it all to one side of the fulcrum meaning that it takes a larger effort on the butt side to make the a change in the muzzle direction than it used to. You could even (and I do) extend your bipod out a few inches (or quite a number of inches on <24″ barrels) in front of your muzzle making the system as rock stable as it could possibly be.

Here’s how stable it is: I don’t carry toe supports for my rifle anymore. I don’t need them. Ever again. The video below is using a BDC reticle which is sensitive to hold by its very nature. I got my 2nd highest .223rem score with the BDC on it only because I had the BipodEXT on it too.

I could spend all day telling you about every detail and if you want me to, drop me a line at ballisticxlr@gmail.com and ask me. If on the other hand you’re willing to accept that someone that knows what they’re talking about is telling you that with one gadget your groups will shrink, your hits will increase, your misses will decrease, you’ll have more fun and you’ll not have to spend a HUGE amount of money to get there from here. Usually I’d call that snake oil but it’s not and I’ve taken a year of using the thing to be 100% sure. It doesn’t even matter what position you want to shoot from, the BipodeXt will help you get more stable when properly utilized. It can’t not because trigonometry is what its leveraging (pardon the pun) and you can’t make real numbers work 2 ways in 1 equation. 1 equation always yields 1 answer.

So, now I can say without a hint of gun writer contrivance or the slightest prevarication that this is the best 300-500 bucks you’ll spend on your long range shooting rig. You will thank me later. If I didn’t know it’s helping me I wouldn’t take the extra effort to hump it around all day at my monthly precision rifle match (it’s a hiking match, any weight reduction is good). I leave the thing on my rifle full time because there’s no good reason to remove it given the benefits I get from it. I’m sure you’ll see things the same way in very short order.

You can see the stability I’m getting from that bipod position being so far in front of the usual position at the mid-point of the rifle. Geometry doesn’t lie.