failure to chamber, Savage 1928A1

[Dan Emmett]

 

 

Today my Savage TSMG stripped the first round from a 30 round GI magazine but failed to chamber the round.  The bolt went forward about three fourths of the way, then locked up

I had to give the actuator a smack with a rubber hammer to unlock it at which time the stripped round was ejected. I then fired the remaining 29 full auto with no issues. This has also happened with an AO L drum on about the 10th round. Is this an ammo issue or magazine issue?  Thanks.

Dan

[spall]

Drums have been more reliable for me, given they're effectively "single stack" feeding. Given you're having the same issue with not just two different mags, but two different kinds of mags, I'd rule that out for now.

What kind of ammo? What was the orientation of the round when it got jammed? Have you had the gun long?  Previous issues?

Is the recoil spring in spec? Is the bolt in good shape? When's the last time you cleaned it?

Are you sure it jammed on the round, and it wasn't a chunk of brass, bent felt oiler, etc hanging the bolt up inside the receiver?

Lots of questions...

Edited August 31 by spall

[Dan Emmett]

Thanks for the reply.

Winchester 230 grain ball ammo. I don't know the orientation of the round but assume it was angled as it did not make it into the chamber given the position of the actuator.

Ive owned and fired the gun for one year, probably 1000 rounds with no issues. Recoil spring is a Wolfe 5 percent power increase, bolt is like new as is the entire gun, I clean after every firing to include the chamber, no brass and the oiler is fine. 

Thanks.

[reconbob]

   Next time this happens remove/eject the round and look at the sides of the case. I will bet you that there will be some type of scraping or damage to show where and how the cartridge was jammed. A narrow scratch at the top would indicate it was dragging on the feed lip of the mag. If there is a half moon dent and following scrape on the lower side or bottom, it’s the feed ramp or the mouth of the chamber causing the jam. When I say top, side, etc. I mean the position of the round in the mag before it was fed.

If this is a rare occurrence it could be the mag. Some mags do not feed the top round from one side or the other. You can polish the underside edge of the mag lips that contact the cartridge with medium/fine emery cloth.

The fix may be to identify and stop using that particular mag. But since it happened with a drum I would look feed ramp/chamber. Again best thing would be to save and examine the rounds that jammed instead of firing them.

i assume the barrel is an original GI barrel. At least half of the new mfg. Thompson barrels out there are chambered using a standard available anywhere .45 ACP reamer or have a standard .45 ACP chamber cut with a single point boring bar on CNC lathes.

But the Thompson chamber is wider and more funnel shaped than the almost straight walled .45 ACP chamber. Nobody sells a true Thompson dimension chambering reamer. I had a custom reamer made to Thompson specs and we use it all the time to turn .45 ACP chambers into Thompson chambers. The difference is not much but turns a gun that will jam on feeding into a smooth reliable gun.

Bob

[Dan Emmett]

Thanks Bob,

 

[Rekraps]

Try loading just 29 rounds in the mag and see if that works. If it does, then it has something to do with the max magazine spring tension and maybe, just maybe the magazine feed lips are out of spec on one side or the other, or both. I bought the feed lip repair tool off this sight and realigned every magazine I own. Some really needed it, while others just a bit. In every case, i could not see the difference by eye.

[Dan Emmett]

Thank you.

[timkel]

Some dummy 45acp cartridges would be helpful to determine the cause.