Introducing .45 Cinderblock

Here’s the beastie. It’s a 1915 manufacture Swedish Mauser action with a Timney trigger, Troup Systems .45ACP conversion barrel with a short .45acp chamber and magazine adapter, custom black oak stock and Williams peep sight and of course a 1911 magazine.


I take .460 Rowland brass and cut it to .888″. Add deeply double digit loads of Hodgdon LongShot or Ramshot TrueBlue, a magnum large pistol primer and either a 200gn Bear Creek HBRN moly coated lead (hollow base round nose), 230gn RN, 200gn LSWC or a 185gn Nosler Custom Competition JHP. Velocities are nominally 1780FPS with the 200gn lead hollow base. Any faster than that and they turn into 4″ long lead darts. With the 230gn RN I’m able to push them to 1900fps. With the 200gn LSWC’s I’ve gotten them as high as 2100fps. When you make the SWC’s go over 1500fps they make a roaring sound which is super neat. I get 2100FPS with the 185gn jacketed bullets. I know I can squeeze a little more velocity from it and have but there’s no reason to.

The cast lead bullets at that speed are best left to close shots at light bodied critters like blacktail deer, coyotes and bobcats. The bullets don’t come apart but they do substantially deform and penetration can be erratic on larger bodied game. If you want to go for bear or even tule elk the 185’s offer amazing penetration and don’t suffer from substantial core/jacket separation and the 230gn RN penetrate like liquor stores in a ghetto. The reason I use the Nosler Custom Competition bullets at all is their toughness and ability to hold together under these extreme velocities.

Here’s the 185 grain Nosler. These are not a bonded bullet but they manage to hold together like a bonded core bullet. I’ve driven these over 2100fps at 1/4″ mild steel and they penetrated clean through. On light bodied game they’re absolutely devastating at high velocities.

Here’s the 200 grain Bear Creek HBRN. The hollow base makes them appreciate being loaded really stoutly or seated deep. Either way you gotta pick the pressures up or leading can be an issue. You want to get the pressures up so the base is able to obdurate and fill the bore to avoid gas cutting and related leading. This bore filling action is how I’m able to get such high velocities.

I can already hear you asking about .45ACP brass. Well, I’ve used it extensively and apart from primer pockets loosening when I get overly exuberant about powder charging they’ve held together exceptionally well. Remember, the .45ACP pressure limit for pistol use is in the low 20K psi range because of an unsupported section of the case which is necessary to allow reliable feeding in auto pistols. In a bolt action rifle that’s not an issue. We can seat that case deep in the chamber if we want but in any event it’s well supported all the way to the case head. The pressure holding capability of normal .45ACP brass is pretty stout in my experience.

.45Cinderblock provides performance capability from .45acp to .454Casull power level in a 1911 magazine. It uses .45acp chamber dimensions with .41magnum level powder charges. .460 S&W power levels can be attained using the same bolt action rifle conversion and .45WinMag brass.

.460S&W, .454Casull, .44Mag, .45ACP/Cinderblock, .22LR

.460S&W, .454Casull, .44Mag, .45ACP/Cinderblock, .22LR

As a case in point, I’ve loaded as much as 12grains of Unique under a 200gn bullet using Remington brass and fired 6+ of those kind of loads from the case without substantial primer pocket loosening. 9.8grains of Unique seemed to be the sweet spot as far as performance per unit powder consumed with Unique. Remember the .45acp charge for ball equivalent ammo with Unique and a 230gn bullet is 5.8gn. I’ve done deliberate double charges and it’s perfectly safe in a rifle. I’ve gone as high as 14.5gn of Longshot in a .45acp Remington case (this is over book for .460Rowland and double pressure for .45acp) and had the primer pocket loosen up too much to reuse the brass.

There's only 1 powder that's perfect. Hodgdon LongShot.

There’s only 1 powder that’s perfect. Hodgdon LongShot.

With .460 Rowland brass I’ve gone even further off the reservation. I won’t say how high but my rifle only loads have been higher than 16grains. This is fine territory to play at as long as loading procedures and tolerances are extremely tight. Seating depth changes of .002″ make a difference at these levels and all the charges above 14grains are going to compress so it’s not something to just play around with. I found that a .1g charge variance at the very top of the range (which is not a safe place to play in the first place) made the difference between pierced primers and not pierced primers. Probably the neatest part about loading for .45 Cinderblock is what you see when you drop the hammer on a full-house load. The gas volume that comes out of the muzzle is just tremendous and you’ll certainly be surprised that you can get that much gas out of that itty bitty .45acp case.

If you’re ready to walk on the wild side and willing to sacrifice a bolt action rifle with a .308 bolt face you can have a really amazingly powerful and handy rifle that you can also feed .45acp pistol ammo to. Your little girls can shoot it with pistol ammo and you can shoot it with full house ammo. The one thing you need to do for sure is bring plenty of extra ammo to the range. Whenever I bring my .45 Cinderblock to the range I end up getting to hand it to at least 5-10 people that want to try out some .45acp compared to my full-house Cinderblock loads. They always hand it back with a huge grin and the wheels inside their head spinning.

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