GJ M24 - Spring upgrade

so i upgraded the spring - its a metal v2 solution which was behaving fine previously

i’m sure it behaved correctly before putting it into the stock also but…

so the behaviour now is, grab the charge handle, pull back, all good

go to push forward to lock the bolt back into resting position and the plunger / trigger assembly releases

if i don’t go to push it forward it’ll hold it there all day without fuss

so…what have I done wrong then?

Turns out it’s the receiver stretching / flexing so I’m told

They question then becomes, who’s done what to reinforce the receiver successfully?

I was thinking a metal putty and more through bolts from both sides