9 replies to this topic

[Got Uzi]

I have a PPSH-41 Im working on and its not feeding from the drum. It fires when the round is in the chamber but not when feeding from an ammunition source. Im waiting on some regular stick mags to come in but does anyone have any ideas?

[BillyDixon]

is your recoil spring strong enough to push rds out of drum ? just askin

[Got Uzi]

Yes it will go full stroke to chamber a round but its loosing bolt velocity somewhere. The bolt is not dragging on the drum as I can leave a round in the chamber then drop the bolt...BANG but if it feeds a round out of the drum, it will fully chamber but go THUD

[huggytree]

I heard drums have to be tuned to the gun. Try a few drums. I dont own one but at one time was in the market and was told drums can be fussy. 50%+ of guns Ftf seem to be mag issues. Maybe 95%

[StrangeRanger]

You need to mention that you've converted it to 9mm, it makes a difference.

 

Just guessing here but look at the front of the drum where the rounds get pushed out.  It's configured for the bottlenecked 7.62x25 cartridge.  The straight-walled 9x19 may be catching the mouth of the case on the edge of the opening.  If so 30 sec with a Dremel will solve that issue.

 

The other thing to look at is the feed ramp area.  Because the larger bullet diameter will cause the cartridge to feed at a steeper angle the 9mm may be slowed down just enough to be a problem and will require a bit more ramp than the 7.62

[jl7422]

Try a few drums. We tried a dozen initially. About half worked right off the bat. Offed the rest to the next guy to try in his. (That's probably why you see multiple serial numbers on the drum covers)  

[Roland the Thompsongunner]

The drum may be a bit too high in the gun or someone may have made winding spring pressure in the drum too high causing excessive drag to strip out the round. Try different drums as all stated above. When I bought my gun way back the drums were 10 for 100 bucks so i bought 20. Only around 5 or 6 worked well. The rest needed work..some did not fit in gun, some were extremely loose and wobbled and some the feed lips were bent and the rounds would not feed and release smoothly from the drum. Try sticks too they work much better and the rate of fire is faster and smoother. As noted also above is caliber conversion. 9mm makes feeding more difficult. I have two drums that feed 9mm well the rest are headaches but work in 7.62 well. Also try different recoil spring and also different bolt if no luck as they vary too fitting loose or tight in the receiver. You will get it worked out just takes patience

[Got Uzi]

Well....I got it to feed from the mags....a couple of them. Appears they will need to be fitted a little bit. Now I have another issue....hows much tension should the rear latch have with the spring? The latch is vibrating forward and let the receiver swing open. Im going to presume it needs to be pretty darn stiff but I want confirmation on this

[StrangeRanger]

The dummy gun on Sherman3's table at OGCA took a lot of effort to open, more than my arthritis was happy with.  It's not intended to be "easy access"

[Roland the Thompsongunner]

They do not need tonbe very tight they just need to lock up firmly And have no up and down slop between upper and lower. Mine was like that and would pop open which is dangerous and also let the bolt move up enough after firing that the empty casing would not hit the ejector correctly causing jams. What i did was remove my serial numbered rear cap off and got another. Then i added someweld to the tab that locks it down and then hand fitted it with a file so when the catch slides into the lower the upper and lower are tight. This made a huge difference on my reliability and the gun runs pretty much 100 percent