Autoloading for Rimmed Cartridges

[LoneCoon]

I notice the other day as I was loading SKS stripper clips that a .38/.357 fit perfectly into it. This got me thinking about the problem with loading rimmed cartridges into magazines.

If the magazines were designed like stripper clips, what's to stop manufactures from making reliable and (more importantly) less expensive firearms in rimmed calibers such as .357 and .45 LC? Assuredly the technology is there, as is the demand for such firearms.

Or do they do this already?

 

[Technosavant]

The Desert Eagle is available in .357 and .44 magnums. There's not much point in a .45LC semiauto; .45ACP is plenty competent enough.

The issue isn't so much the function, it is the size. .357, .38spl, and .45LC are rather long cartridges, and a resulting autoloader would end up with an enormous grip size. Keep in mind the strength of some of those rounds, and it's no surprise why the DE is so huge, and why it isn't as practical a firearm as some might think.

 

[SDC]

There have been a couple of attempts at it, but the rims cause more trouble than they're worth; either they stack up so fast that you end up needing a magazine (and a mag well, and a grip, in the case of a handgun, that looks like a crecent moon), or the rounds end up jiggling around to the point where you get "rim-lock", ie. the rim of the top round ends up behind the rim of a lower round, and it jams.

 

[Gifted]

The idea has merit, but machining a groove like that that has the tolerances that can make it work might be prohibitive. Feeding a magazine isn't nearly the same as a stripper clip. You also have the problem that just the back end of the cartridge is supported. The size of the rim means there's a considerable gap between the bodies. And how would you extract the next round from the magazine for chambering without it possibly fouling on the next round?

Guns like the 10/22, Dragunov, Desert Eagle and such use a different tact. The magazine has a slot halfway across the lenth. You insert the rim here, and push back. When the next round is loaded, the rim is in front of the last, avoiding the "rim lock" problem mentioned by SDC. When the action cycles, the round is pushed forwards, and when the rim hits the slot made in the middle, it allows the round to be pushed up out of the magazine for chambering. It works too well to mess with, though I've heard that too many rounds in such a magazine can cause problems.