Why no smallish 22WMR Semi Auto's

Back in the 80's the FBI did some serious testing on the Grendel P-30 as a BUG.
They liked it, but the ammo of the day held it back...

Having owned a P-30 for the better part of 15 years, I've tested the crap outta it...
Done a keltec fluff & buff on it, and feed it the highest quality ammo I can get...
Got no problem carrying it as a primary EDC due to the 30-rd mag...
so what if I gotta shoot a guy 5 times, still got 25 left, plus two more mags... ;)
You can keep a lot of heads down with 90 rounds...

Nowadays chances of a FTF are on par with anything else. Rare, if you choose good ammo.

If the KT was more available at its MSRP, I'd have one...but I ain't paying a scalper for squat.
I'll wait until I find some schmoe selling one to a pawn shop & cut a deal.
 
Another thing to consider is the .22WMR is too hot for the usual blow back design used in the smallest pocket pistols. This, combined with the length of the round means the pistols have to be bigger than ones for shorter lower pressure rounds.

They may not have to be a lot bigger, but they do have to be bigger.

The Automag II used a retarded blowback system, and they were picky about ammo. I had personal experience with 3 different guns that friends had. One ran fine on everything. One would only run on brand A ammo, and choked on everything else. The other would only run on Brand B, and choked on everything else.

I don't have any personal experience with the Grendl.
 
I believe the Automag was made in a short, pocket sized version.

I'm another one who would buy a PMR30 if they were easily available, and the carbine version really interests me.

Maybe Ruger will copy the Pmr30 and mass produce it, like they did the P3AT/LCP.
 
Just received my PMR-30 it was 350 out the door,have not yet shot it so I have no idea about the rim lock they talk about but I guess if you take time and load the mags right it's not a issue,I'm on the top of the list for a CMR........
 
I have no idea about the rim lock they talk about but I guess if you take time and load the mags right it's not a issue...
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Rim lock can be an issue with any rimmed or semi-rimmed case used in a semi-auto magazine.

If you load the top round in such a way that its rim ends up BEHIND the rim of the next (underlying) round in the mag, when that top round is pushed forward by the slide or bolt, its rim will catch on the rim of the case below it and the slide/bolt will simply STOP, slow or otherwise not function properly. Kel-Tec's follower/mag design seems to make this less of a problem than with other rimmed or semi-rimmed cases.

The manual says load five rounds and then tap the back of the mag against a flat surface. Then do it again. If you plan to load all 30 rounds, when you get to the last 9-10 rounds, tap the back of the mag against that surface with each 1 or 2 rounds loaded.

So far I've run a number of mags through my PMR-30 and haven't taken any special pains to avoid rim lock. But I've typically don't fully load the mag -- I like to shoots in smaller groups, and examine the target more frequently. I've just loaded the mags and fired away. I haven't seen it mentioned as an issue in any of the PMR-30 discussions on the 'net, but it may be that everyone is following the manual instructions.
 
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If the short length of the barrel is a problem, why are the NAA mag revolvers so popular? There has to be a more serious problem. Perhaps the increased length of the cartridge makes the grip too wide. However, the popularity of the PMR30 would argue against that. So it must be that mfrs question whether it would sell.

willr
 
If the short length of the barrel is a problem, why are the NAA mag revolvers so popular?
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The length isn't really a 'problem' it's just that the .22WMR doesn't develop much more velocity in a 2-5'' pistol barrel compared to .22LR

Out of a 4.625'' bbl I have sources claiming about 1050FPS for a 40 grain .22WMR

Compare that to a .22LR 40 grain 'velocitor' out of a 4'' bearcat which the same source claims 1044FPS
980FPS for the CCI minimag from the same bbl
Not a whole lot gained there...



Why are the NAA mag so popular?

Because despite more blast/noise and a fairly negligible increase in velocity, you still gain things with WMR, other than pricier ammo.

On a whole, .22WMR tends to be more inherently reliable in its ignition, which is a huge plus for SD. Higher quality ammo. Better jacketed bullets, and potentially heavier projectiles (excluding the Aguila SSS which will not stabilize in most pistol barrels)

Also the NAA mag are usually compatible with .22LR conversion cylinders, so you can technically buy a NAA mag, and then use it as a .22LR pistol, if desired. I'm not sure if it works the other way around, since the WMR should require a longer cylinder.
 
Many Moons ago when Winchester and CCI were about the only 22mag game in town I recovered a CCI MiniMag HP from a Coke can! Absolutely perfect condition except for the rifling grooves, it was shot out of a 2" H&R. I still have the box my Automag came in and it cautioned against CCI ammo due to the chance of fouling the Automag's chamber ports. Maybe today's magnums are loaded with a slightly faster burning powder, I know that little H&R magnum could wake the dead!:eek:It was great with shot shells though.
 
If the short length of the barrel is a problem, why are the NAA mag revolvers so popular?
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Because some people believe "magnum" is a magic word?

Because folks buy these guns without doing any research into their effectiveness.

Because there isn't a lot of info available on the ballistic performance of these short-barreled guns using .22 WMR, etc., etc.

I can think of a lot of reasons...
 
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The NAA 22 Mag blast from a 1 5/8 barrel scared the crap out of me one. I shot the gun in an indoor range between the two side walls of the lane.

BOOOM! I thought I blew up. I could feel the blast wave come back at me and go under my glasses. I slammed my eyes shut reflexively. No other gun in a similar range ever did that.
 
Anything smaller than a PMR needs a full on locked breech, at which point you might as well do a 32acp or 380.

TCB
 
I don't understand fully how it works, but the PMR-30 has a hybrid system, using both locked breech AND blowback features. The barrel and breech move, but blowback also powers the action.
 
I thought I read one time where the muzzle blast from a short 22mag at "belly gun" distances added to it's wounding potential?
.
 
The main problem is reliability. Heck, Ruger even had to give up on the 10/22 mag rifle, which was a proven performer in .22 long rifle, but they had too much trouble with it, when they tried to market it in 22 mag.

It maybe related to over all length, but I thing it's also related to the power or shall I say pressure spike.
 
I suspect, but don't know for sure, that short barrels make the .22 WMR round perform only a little better than a .22LR. And then there's the issue of capacity.
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All that extra case length/powder capacity does is translate primarily into more flash and bang at the muzzle and more pain at the cash register ...... not a whole lot more f/sec when there is not enough barrel to burn it in ......


The case itself is longer, which means a longer slide ...... more expensive ...... and in the short barrels, little gain in velocity ..... where's the upside?

There isn't. ..... so there aren't any small WMR pistols, much the same way that there are not any Celicas with tow packages, or submarines with screen doors.
 
Another point is that the unburned powder might quickly foul up a semi.

I had a SW 651 revolver and a 50 round range trip, gunked it up so much that the cylinder wouldn't rotated. I had to soak it in the Marianas Trench for days (joke) to free it. Then I had to take it apart to get all the crap out.

I imagine a semi would be worse.
 
"but the PMR-30 has a hybrid system, using both locked breech AND blowback features. The barrel and breech move, but blowback also powers the action."
It's a straight blowback with some tricks to safely run 22mag on a slide/bolt that light. First the chamber is fluted to reduce the peak friction force of the case wall, which prevents tearing during extraction, and the second is letting the barrel move back a short ways under what case friction there is, which is sort of like 'locking' the breech to the barrel using the case itself as the link. Not super effective compared to a real locked breech, but it does reduce the bolt mass required a little bit. The five-seven came up with this first, but they use lubricated cases instead of chamber flutes.

TCB
 
barnbwt said:
It's a straight blowback with some tricks to safely run 22mag on a slide/bolt that light.
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You say it's straight blowback and then go on to tell us that it uses tricks that aren't straight blowback. I would argue that it is, as I originally stated, a hybrid system. Wiki, when describing blowback systems, says:

"The simple (sometimes referred to as the "straight" or "pure") blowback system represents the most basic form of blowback operation and demonstrates the basic principles involved in the blowback cycle. The simple blowback mechanism typically consists of the bolt which rests against the base of the cartridge case and a recoil spring that is compressed by the kinetic energy of the bolt when it is thrown back in recoil. The stored energy of the compressed spring then drives the bolt back forward into firing position. "​

The barrels of straight blowback guns are also fixed; the PMR-30 barrel is not fixed. The Wiki article goes on to describe other blowback mechanisms, but none of which seem to match the PMR-30 system. The PMR-30 has traits of both the basic and delayed blowback systems (using what, to this layman, might be a variant of the "chamber ring-delayed" design); the system seems to work a bit like the PMR's fluted chamber. There is also, as you note, a locking function not typically present in straight blowback designs. It seems to be timing and pressure (and, maybe a fluted chamber) rather than links and barrel lugs. Here's what Tobias Obermeit, the chief designer at Kel-Tec had to say about the PMR-30 system:

The hybrid locked/blowback system is simple in execution. There is technically no mechanical lock in the gun but it is locked: the cartridge case is the lock in the system.

The friction of the case locks the chamber (and therefore the barrel) to the case as they both recoil together….as long as the pressure is high enough. Lower pressure rounds will cause less friction between the case and the barrel, and then the barrel stays still, or only moves a little…..It’s a balancing act between the bullet friction pulling the barrel forward, and the case friction in the chamber pulling the barrel back. Bullet friction does not change much based on round pressure, but the case friction will.

See more at: http://www.thefirearmblog.com/blog/2010/10/12/gun-design-engineer-answers-your-questions/#sthash.PrWNOlCZ.dpuf​

Obermeit also answers the question I asked, earlier: is it possible that the PMR-30 might work in a self-defense situation:

Do you believe that the .22 WMR is an adequate man-stopper?

I do not believe that a single .22WMR out of a pistol is adequate…but I do believe 25 to 30 .22WMR’s are adequate. It’s not ideal, but the total amount of bullet weight in a full 30 round mag is 1500 grains (if 50 grain bullets are used). This compares to 10 rounds of 147 grain 9mm, or 13 rounds of 115gr. Of course bullet weight alone is not enough, but the velocity out of the PMR-30 is still quite good. (1230fps for 40 gr)​
 
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