I have a USGI M1 Carbine ('43 Underwood). I only have newer aftermarket M2 style mags with the bolt hold open follower. As stated, I get pretty consistent FTF on the last round in mags. The bolt pushes the round slightly and then hangs up. If I rack the bolt back and release it, the round then chambers and the rifle fires without problem. No problems on the first four rounds which chamber properly. I checked the spings in the mags and they are put in the correct direction so that's not the issue as far as I can tell. Any suggestions as to what to look for?
M1 Carbine FTF Last Round
- Thread starter RK99
- Start date
I'd say your mag latch isn't holding the mag quite high enough, or at not quite the right angle. I have had that issue with M1 rifles before. Next time try wobbling the mag to see if it releases and feeds. The angle at which it does so will point you to the adjustment you need to make.
I actually installed an M2 mag catch as mags weren't staying in or locking in properly and no rounds would feed properly unless I put pressure on the bottom of the mag. The mags are seated and tight now with the newer catch. The first 4 rounds feed normally without problems. It's just the last round that's a problem. I'll try as you suggest but it's weird that only the last round would have a problem if the mag was loose or wobbly.
those aftermarket 30/5 mags are not know for reliability
a few things I have found
pinning IF pinned with a rivet through the back it can do two things bind on the mag catch preventing proper insertion
2 the rivet if too long can bind the magazine spring prevent full spring force on the follower get a shorter rivet OR file the rivet inside the mag shorter
mag lips are often malformed on aftermarket mags some tweaking can sometimes correct it (or totally wreck the mag) go slow with small corrections I use calipers to measer lips on a known good magazine
get usgi 15/5 rnd mags they are better
a few things I have found
pinning IF pinned with a rivet through the back it can do two things bind on the mag catch preventing proper insertion
2 the rivet if too long can bind the magazine spring prevent full spring force on the follower get a shorter rivet OR file the rivet inside the mag shorter
mag lips are often malformed on aftermarket mags some tweaking can sometimes correct it (or totally wreck the mag) go slow with small corrections I use calipers to measer lips on a known good magazine
get usgi 15/5 rnd mags they are better
Mags really seem to be an issue. You see a guy recommend 5/15 mags whereas I have gotten all my 5/30 to feed but now 2 of my 3 5/15 don't feed the last round. My problem may not be your problem but I have had it with two M1 rifles. Both guns had the old style mag latch and both had to be fitted with M2 latches. One even needed some JB to get it sitting right but that is just a lame Auto-Ordnance repro.
It seems to just be variances in quality and dimensions from different manufacturers. The issue is moreso the position the mags are held in based on the exact latch points on a specific magazine. My 5/30 are all held mostly by the side latch point. The 5/15 ride the two on the spine tightly and an Auto Ordnance 5/5 I have rides the spine just the same but it completely reliable after fitting the catch to the rifle. I wish I had it all ways but it was a lot of fiddling just getting most of the 5 dozen mags I have working.
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Any idea where to get USGI mags in Canada? I haven't seen any for sale anywhere.
I'll try tweaking and tuning the mags and see if that helps. As you say, they are a weak point. Apparently during WWII GIs would just replace their mags frequently, often grabbing new ones when they got more ammo, just disgarding the old ones. They seemed to recognize the lack of reliability there. I may also replace the recoil spring as that is a recommended fix when feeding issues happen too. The one in there might very well be the original post war refit spring.
fingers284
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I would suggest looking at the follower for a drag on the brass issue. You say it feed the first 4 as it should suggests to me that it isn't a mag lip or mag catch issue because they are in the same orientation to the action/feed ramp for the first 4 rounds as the fifth. I would try polishing the follower anywhere a round contacts it because it sounds to me like the smooth brass-on-brass friction is somewhat free'er than the brass-on-steel of the last round.
I had thought about looking at the followers. They are plastic, not steel, on the reproduction mags. But they may still be dragging on the round. Thanks.
