AR mags loose in magwell
 

I've got a TM M4A1 with a guarder metal body and one piece hopup. It has been in that configuration for 2 + years now. Recently my mags have had trouble feeding. There seems to be to much up and down movement, at least a few milimetres. I have to hold the mag up in the magwell for it to feed properly. This happens with my TM & KA lowcaps and my CA & SRC highcaps. Now my SRC M16 with G&P metal hopup and metal body doesn't has this problem at all. I tried switching out the mag catch but it had no effect. I'm wondering if the hopup feed tube in the G&P unit is a little longer then the guarder one, but I don't think that would explain why the problem started just now.

Try tapeing the top of the mag around and around utill you get a proper fit to hold it in place.

are you using plastic mags? they could just be wearing, in which case metal mags would be the way to go

All the mags I've been using have been metal.

could your mag catch on your gun have worn out?

I tried switching my mag catch between my 2 ARs with no luck.

try bending the tab at the top of the mag out a little, i know this problem exists in some G&G guns and thats how you fix it

Do you think it would matter if one of the tabs on the upper receiver was broken? The tab one the selector switch side is broken.