SVT-40 magazine troubles

lonesalamander

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Hey everyone

I've had my SVT-40 for a couple months now, and I've had a lot of fun just playing with it at the range- maybe 600rds. of surplus through it thusfar.

However, things have been really spoiled for me because the gun tends to jam on the second (~75%) or fourth (~25%) shot- failure to feed. My observations have been that this is most likely due to some fault in the magazine. Rounds that jam tend to feed out at a 30 degree angle, miss the chamber and hang up on the rear face of the breech. Alternatively, they will feed half way into the chamber and I will have to slap the bolt handle ala forward assist to get the gun into battery.

There are two potential sources of this to my eye:

1) the feed lips look like they are causing too much friction- they're either improperly machined or have been dropped and bent at some point. This is what I think is the most likely cause.

2) the ramp on the front of the magazine doesn't look like it has been profiled properly. When I'm feeding rounds through the magazine by hand, rounds staggered to the right hand side of the magazine tend to hang up on the very edge of the ramp. During firing, spring tension generally tends to be enough that rounds are not hung up on the ramp.

I'm probably going to start troubleshooting this by gently bending the offending lip outwards to both reduce friction, and maybe give some clearance for rounds as they hit the ramp.

I've attached pictures of both the lips and ramp. I'd like to know if anyone has any commentary before I potentially mess up my one and only mag. If anyone can compare them to their own SVT-40 mags, it would be helpful to know how out-of-spec mine are and whether or not I'm going to have to break out power tools.

http://i54.tinypic.com/2mnq3af.jpg
http://i53.tinypic.com/avo40j.jpg
 
Guns weren't meant to be worked in slow motion. Because of this I feel your troubleshooting might be yielding a false impression of the problem. I would recommend adjusting the gas system before any more drastic measures are taken.
 
How far is the rifle throwing the empties?

If they are just dropping out, then chances are that Zippy the Wonder Chimp has hit the nail on its head. ALSO, it should not be winging them halfway to Arkansas, either.

The Tokarev is a gas-operated action and the gas must be adjusted correctly in order that the mechanism be given the impetus it requires in order to operate efficiently. On the Tok, using too little gas will give all sorts of problems, including the one you describe. Using too much gas gives a whole new set of problems, generally including but not limited to, a general loss of accuracy.

The ideal gas setting is with the rifle operating smoothly and efficiently AND throwing the empties no farther than a few feet from the rifle. This will give your best accuracy and with minimum strain on the operating parts of the rifle.

Hope this helps.
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Guns weren't meant to be worked in slow motion.

Yes I acknowledge this. I mentioned that the spring tension will generally cycle ammunition out of the magazine. My concern is that the rounds are being fed away from the chamber as they are possibly being "bumped" over the edge of the ramp.

How far is the rifle throwing the empties?

They generally go 3-4 feet. Gas is set at 1.5 atm. The first 500 or so rounds were at 1.3 before I bumped it up for a session.

If the problem were gas setup, would I not be encountering jams irrespective of "which shot" it was vs. almost always on the second shot correct?

Lets assume that gas is an issue- the fact that I consistently jam on the same shot would indicate to me that this gas issue would only be exacerbating a possible magazine issue.
 
It's a feeding issue, not ejection.
It's not friction. The cartridges aren't coming out of the mag at the proper angle. If you do open the lips, use long, fine, needle nosed pliers. Just tweak the lips open a wee bit. It doesn't take much to alter the angle. No power tools. Clean the mag too.
 
I have the same problem with my SVT-40.I have tried starting with the lowest gas setting and turned it all the way up in increments.On mine it is almost always the right hand cartridge that hangs up on the bottom of the breech face, so I took some needle nose pliers and opened up the mag lips a bit.Still no luck.The mag seems to have a bit of play in it so I think it might be worn a bit where the mag meets the feed ramp therefore causing the round to come out at to shallow of a angle to clear the bottom of the breech face. Unfortunately spare SVT mags are as common as hens teeth so I really don't want to experiment on my sole mag too much.By any chance if there is someone on CGN in Edmonton that goes to the CHAS range on weekends with a SVT that would let me try their mag in mine please PM me.If it works I'll let everyone know.
 
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