I found this on airsoft armoury, they look like a real help, and it says tey work for the agm mp40. Just to confirm do they?
IIRC, they're utter cack.
I've got some and they are good, it's just a pity they're made of plastic. If you have an older MP40, there can be issues with inserting them (they need a good whack) but, overall they feed ok and it means you don't have to cart around a load of 50 round locaps.
When I want your opinion - I'll tell you what it is!
Don't listen to Headshot...
They're fecking ace! I love mine! They feed perfectly. I've not had a single jam.
The only downside is that in order to get them to fit there is a minor mod that may need to be made to your MP40 magwell. It doesn't stop other MP40 mags fitting as well and doesn't apply to all AGM MP40s.
Maybe I'm thinking of Star.....
so do you always have to do a minor mod, or sometimes can they fit staraight away. Or what sort of minor mod?. And isnt there also a way of making a hicap by using an uzi magazine?
Read this thread and all will become clear...
Its long but contains all the answers you require! 
Mine didnt need the mod done - Just give them a few whacks by fitting and removing a couple of times and they then fit a treat.
Meine Ehre Heißt Treue
SS-Rottenführer Kotzur
Zweite Kampfgruppe
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Used mine at a walk on at GZ last Sunday, worked flawlessly. Mine is the 'older version' MP40 (if there is such a thing) you just need to give the mags a nice whack when you put em in and no worries or mods required either!
'shokt
"The older I grow the more I distrust the familiar doctrine that age brings wisdom"
H.L.Mencken
