Avoiding the dreaded "rim lock".

[gunfan]

After perusing the Savage site at length, I came across the link to the site's "rimlock" page. What causes it, and how it can be avoided.. Anyone that shoots a semi-rimmed cartridge can, nay, will benefit from reading the page. Some of the information reads:

a) Slide cartridges into the magazine, and let the rims of said cartridges rest against each other.

b) Don't "tap the magazine" to seat the cartridges into it. This can cause the rim of one cartridge to slip over another and create the dreaded condition.

c) Don't use cartridge of differing overall length. This can tempt one into seat the cartridges against the back of the magazine. Insert the cartridges into the magazine firmly, yet gently. IF the magazine is in good operation condition, it should feed quite well.

I paraphrased some of the content, but the message is the same. insert the cartridges as the mechanism was designed to accept them, and generally speaking, you can avoid rimlock.

Scott

[Idaho Sharpshooter]

No offense, but; there is no such thing as a semi-rimmed cartridge. Cartridges have rims, or they don't.

It's like saying "I'm a little pregnant.". You are or you aren't.

Which cartridge(s) are they referring to?

regards,

Rich

[Alan]

Well, the Colt semi-rimmed were all Browning concoctions - .25, 32, and .38 ACP. The .25 has the most in relation to the cartridge. The .32 has enough of a rim to fire in most .32 S&W and .32 Colt New Police revolvers. The .38 has enough of a rim to cause 90 years of utterly miserable accuracy. ;^P

[44man]

No offense, but; there is no such thing as a semi-rimmed cartridge. Cartridges have rims, or they don't.

It's like saying "I'm a little pregnant.". You are or you aren't.

Which cartridge(s) are they referring to?

regards,

Rich
But there is. They have an extractor groove but the rim is larger then the case base. Then you have rimmed, rimless, belted and rebated.
Gunfan is correct about the problem.

[Dan Cash]

Must be something in that Idaho water.

[Chicken Thief]

http://t3.gstatic.com/images?q=tbn:ANd9GcQqrwX8jLiFaOGee5RdHoGDENSxE1qRI setkvt9AptnIhfdtNBbfwhttp://t2.gstatic.com/images?q=tbn:ANd9GcTJP5zcl9N68mQjbVFCS7BUZ75KXXIsj _ubRPIxgpLXPnXaN0IO

[jblee10]

The 220 Swift is semi rimmed and was once common in bolt guns.

[grendelbane]

My experience with semi-rimmed cartridges is only with the .32 ACP and the .38 Super. Never really had a rimlock problem with either one. I suspect most of the problems are caused by shorter than usual cartridges.

If it hadn't been for that silly semi-rim, the .38 ACP would have been the world wide choice of 9mm type handgun cartridges, and the 9mm Parabellum would have been a footnote in cartridge history.

Give JMB credit. He took one look at the new 9mm Parabellum cartridge, and every cartridge he designed afterwards was rimless. It is a shame that Colt didn't introduce some thing like the 9x23mm Winchester cartridge when they came out with the .38 Super.

[swheeler]

220 Swift and 225 Winchester are a couple, 6mm Lee Navy too

[white eagle]

I was going to say the 220 but ya'll beat me to it

[MtGun44]

Yes, there are semi-rimmed cases. .38 Super and .38 ACP are just a couple examples.

IME, it is a total non-issue with semi-rimmed cases because the diam diff is just too small
to make any feeding issue. Also too small to headspace consistently.

Bill