This is a bit of a repost from a previous thread that got no response, but I need some AGM MP40 assistance.
The mag catch on my cheap ass Chinese weapon doesn't protrude far enough out into the mag well to connect with the recess on the mag. It clicks unconvincingly into place then falls straight out. I've had the mag catch off and tried reseating it, but can't make it work. I can't fathom out any way of making it stick further into the mag well without finding a way of building up the catch somehow.
There was a thread on here that suggested shimming the thing to cause it to stick out more, but for the life of me I can't work out how to do that.
Any suggestions would be most welcome.
I just had mine apart (pesky little washer).
I don't see how "shimming" will help at all.
It looks to me like the moving catch part (not the button, the other part) would need to be thinned were it touches the mag housing so that the catch pawl can protrude further into the mag well.
The only problem with that is, not knowing what it's made of, I don't think much metal could be removed before it gets too fragile.
Agree. My other thought was to try and build up the catch with something like epoxy or car filler then file it back into shape. Fiddly, but it could work.
Gah, I wish I could remember what I did to improve my MP40 catch but I'm sure it involved adding a small washer somewhere!
The only thing I can think of that adding a washer could do is to make the release button stick out more.
That's not the problem here.
Mine is looking borderline, and I can guess that with use the catch will wear down more.
I don't have the time at the moment, or I'd have a go at making a new part with a deeper catch.
I read the thread where the washer fix was suggested but I can't for the life of me work out where you would put a washer to make the catch stick further into the mag well. As No1 says, it would only make it protrude less, whcih woul be fine if the thing was sticking and not releasing the mags. My issue is the opposite.
Building up the catch or completely replacing the part are the only options I can see, and I can't find anywhere that sells after market parts.
Heh, all I can say is a few of us solved the poorly-engaging-mag-catch problem with judicious use of a small washer!
As I said, the only thing I can think of that a washer could do is to make the release button stick out more.
I suppose it's possible that makes less friction in the hole, so the spring could work better, allowing the catch to stay in place more strongly, but it can't make the catch protrude further into the mag well.
A washer under the spring would compress it more, making the hold stronger.
Perhaps that's it - Maybe the "washer fix" increases the spring pressure, making the catch less able to move out of place on its own.
OK - I buy that as a remote possibility. Maybe a stronger spring ? I'll have a play and see what happens.
And I quote, from the other thread...
By unscrewing the button and putting some shims behind it, the catch can be made to sit further into the magwell and grip the mag better
Despite 3 misepent years doing an Engineering degree I still don' t get how, but I'll try it.
Physics would contradict that statement. There is no physical way the catch can go any further into the mag well.
As I said in my last post, I think all shimming there will do is increase the hold of the spring. That would grip the mag better, but not by more catch.
I sorted mine out with some spare Marui gear shims. A perfect fit and, done almost 4 years ago, with no problems since.
When I want your opinion - I'll tell you what it is!
I am obviously a massive dumb ass, because I am soooo not getting this. I've been to B&Q and got some washers and there is no way I can work out where to put them. See the pic below...
If I put a washer at point A on the outside of the reciever the whole catch won't recess far enough to connect with the mag. If I put it on the inside it stops the mag release from depressing as it relies on there being a gap between point A and C when fitted
A washer at point B stops Point C sliding over it and means the whole thing doesn't fit
I haven't tried point D as I can't see how this will help
Point E can be achieved by just not fastening the screw as tightly, and this does nothing.
Clearly when the apocalypse comes and we all have to fend for ourselves by our wits I'm screwed, because this just isn't working for me !
I put the shims inside the bit you have marked "D", if that helps?
When I want your opinion - I'll tell you what it is!
I'll try but I really don't understand how that's going to do anything. I'll go hunting for a bigger washer and report back.
Clearly when the apocalypse comes and we all have to fend for ourselves by our wits I'm screwed, because this just isn't working for me !
Alternatively, you could be one of the few that survives because the others are wrong.
I'm with you. There is nowhere on that whole gun that you could put a washer to make the catch come in further. it's a physical impossibility.
Others' responses are confusing "hold better" with "protrude further".
The washers only affect the amount of pressure the catch exerts. if the new catch protrudes 0.5mm in, and mag movement moves it 0,5mm, it'll come out. If the spring is stronger, the catch can't move as easily, so will "hold better". If the catch is worn, the smaller movement will make it lose its grip.
Nope. Makes it worse.
I'm sure that I have a spare one laying about somewhere. I'll have a dig through my numerous gun parts tins.
When I want your opinion - I'll tell you what it is!
Cheers. I have come to the conclusion that mine is just broken.
