Shooting Pistol Ammo In Your
Rifle Is An “Old But Good” Idea
By Dave Anderson
More than a half-century ago a pal showed me a neat little device his father used in a Savage 99 .303. It was a brass cartridge adapter, made by Marbles, I believe.
It resembled a fired .303 Savage case, except the base was wide open so a .32 ACP pistol cartridge could be inserted. Then the adapter was loaded in the Savage rifle, enabling the .32 ACP cartridge to be fired in the rifle.
Why would anyone want such a thing? Lots of reasons. Fired from the rifle, the .32 ACP cartridges were accurate, quiet, virtually recoilless. They were excellent for low-cost practice shooting, for introducing new shooters to centerfire rifles, for vermin control around the farm, for small-game hunting.
On a big-game hunt, the adapter and 50 of the small .32 ACP cartridges weigh little and take up little space. They could be used to take a rabbit or grouse for the pot without a lot of noise or meat damage.
Handloaders are no doubt thinking a handful of reduced-power loads just as useful. And they are quite right, except for a couple of issues: (1) not all shooters are handloaders, and (2) a box of reduced-power loads in say, .308 Win, take up as much space and almost as much weight as full-power loads.
Old timers (like me) may remember the name Harry Owen and his Sports Specialties, which began making chamber adapters some time in the 1950’s. After Owen died the company was acquired by Bill Herrick who continued it under the name MCA Sports.
Recently Herrick decided to pursue other business activities and the company was acquired by Ace Dube of Anchorage, Alaska. Dube is an interesting character, a lifelong Alaskan resident, whitewater rafting guide, licensed hunting guide, competitive shooter and hunter.
A fan of vintage, classic rifles, Dube began casting bullets in order to get some of the old classics shooting again. The hobby became a business, Ace Bullets, specializing in bullets, cases, and loading dies for oddball and obsolete cartridges.
MCA chamber adapters in .22 LR and .22 WMR are made to fit rifles chambered to several popular centerfire .22 cartridges. A steel plug with an offset firing pin fits the adapter behind the rimfire cartridge. Adapters in .30 caliber are made to fit .308, .30-06, and .30-30 rifles. There are also barrel inserts for both rifles and shotguns which deserve to be covered in another column.
Another adapter Dave tried allows the use of .22 Hornet cartridges in a .223
rifle. Since the .223 case is only slightly larger at the base than the .22
Hornet there isn’t enough metal to allow an extraction groove. MCA recommends
this particular adapter only for the break-action T/C single shot rifle or pistol.
The adapter and the Hornet cartridges do shoot, and shoot very well, in a .223
rifle (such as this Ruger American Ranch rifle with Burris 2-7×35 Fullfield scope).
The inconvenience is the need to use a cleaning rod from the muzzle to remove it
after each shot. It would be more practical to use the .22 Hornet with a .22-250
rifle and adapter, which does allow an extraction groove.
Shooting at 100 yards, the Ruger American Ranch rifle in .223 Rem delivered (left)
.223 Rem, 55-grain HP at 3,100 fps. In the MCA adapter, .22 Hornet Hornady 35-grain
V-Max ammunition at about 2,950 fps shot to nearly the same point of impact. The
performance is so similar there’s not much point to this particular conversion. A
.22-250 paired with an adapter for the .22 Hornet would give a broader range of
When the Tikka T3x was introduced, local dealers had their stock of the older T3 models substantially discounted. I took the opportunity to pick up a SuperLite in .308 Win. Fitted with a Nightforce 2.5-10×32 NXS Compact, it is a versatile and useful rifle.
It seemed logical to make it even more versatile by adding a small-game load. MCA Sports has adapters for .308 or .30-06 rifles in your choice of several smaller cartridges: .30 Carbine, .30 Mauser, .30 Luger, .32 ACP, .32 S&W (short and long) and .32 H&R. The .32 cartridge adapters are also offered to fit .30-30 rifles.
I selected an adapter for the .32 ACP, partly from nostalgia and also because I had several hundred .32 ACP cartridges on hand. The .32 ACP uses bullets measuring 0.312-inch in diameter, a bit oversize for an 0.308-inch groove diameter barrel. In practice the relatively soft copper jackets and soft lead core swage down easily.
The .32 ACP is a low-pressure cartridge with SAAMI maximum average pressure (MAP) is rated at 20,500 cup. Since the .308 Win MAP is 62,000 cup, a rifle capable of handling the cartridge can easily withstand whatever pressure increase results from the slightly oversize bullets.
The MCA adapter I tested showed excellent workmanship and appears to be made of high quality steel. In practice it worked flawlessly. The .32 ACP cartridges I had on hand were loaded with 71-grain FMJ roundnose bullets rated at about 900 fps from a pistol barrel. They fit perfectly in the adapter.
The only “fiddly” part of the process was manually feeding the adapter into the chamber. If you’ve ever tried to load an empty case in a rifle you know the sharp edges of the case mouth tend to catch on locking lug recesses or the edge of the chamber.
The T3 has a smallish ejection port making the job a bit trickier. I found by holding the rifle at the receiver (to keep the bolt open) with the left hand, muzzle straight down, it was simple enough to drop the adapter in the chamber with the right hand.
The adapter has an extraction groove so extraction and ejection after firing are no different than with .308 cases. I had a short wooden dowel on hand to push the fired .32 cases from the adapter though it was seldom needed. The low pressure, straight-wall cases generally fell out just by tapping the adapter on a hard surface.
The MCA adapter allows .32 ACP cartridges to be fired from a rifle chambered to
.308 Win. Note the machined stainless steel adapter headspaces on the shoulder
and has an extraction groove like a .308 case. The .32 ACP case fits in the
adapter and headspaces on both the case mouth and the semi-rim. Pretty fine
machinist work! The .32 ACP cartridges are quiet, accurate, with imperceptible
recoil, ideal for training or for collecting small game for the pot.
At 25 yards, .32 ACP loads from the adapter printed about 2 inches low and 1 inch
to the right of full-power .308 loads from the Tikka T3 rifle. Different velocity
and much lower recoil may explain why the .32 ACP bullets hit low, not sure why
they should print to the right. Once Dave settles on a brand of .32 ammo he’ll
record point of impact change and dial the scope as needed.
The .32 case doesn’t hold a lot of powder, but even so the rifle barrel gave a nice velocity dividend. Five shots over the Oehler 33 averaged right at 1,150 fps, a nearly 30-percent increase over the nominal 900 fps from pistol barrels.
This hardly turns the little cartridge into a giant killer. It’s still a rabbit/grouse/small vermin cartridge, which is exactly what I want. And unlike 50 years ago we now have some lighter, faster, expanding .32 ACP factory cartridges. A quick look on the Internet found examples from Buffalo Bore, Federal, Hornady, Speer and Winchester.
I’ve been having so much fun with the .32 ACP in the Tikka rifle I’m thinking of adding an “intermediate” load with a .30 Carbine adapter. And if you aren’t a fan of the little ACP cartridge, the adapter for .32 S&W short and long, and the .32 H&R would be a versatile choice. I’d like to try it in one of my lever-action .30-30 rifles.
Another recent acquisition is a Ruger American Ranch rifle in .223 Rem, fitted with a Burris 2-7×35 Fullfield scope. I thought it might be fun to try an adapter to shoot .22 Hornet in the .223 Chamber. MCA does make such an adapter though it is recommended only for the break-action Thompson Center.
The reason is simply one of size, as there isn’t enough thickness of metal to machine an extraction groove in the adapter. With a break-action design you can simply pluck the adapter from the chamber after shooting. With a bolt action the only way to extract the adapter is with a cleaning rod from the muzzle. If you don’t mind this inconvenience the combination does shoot very well.
A more practical idea would be the adapter to shoot .22 Hornet in a .22-250 rifle. This adapter does have the extraction groove, plus there is a wider range of ballistics between the two cartridges.
These adapters are extremely useful, very well made, and an excellent value. Adapters in blue steel are just $20, in stainless steel $28. The price includes shipping and handling, making an already outstanding value even better.
MCA Sports/Ace Bullet Company, 2800 West 33rd Road, Anchorage, Alaska 99517, (907) 248-4913, www.mcace.com