GHK M4a1 V2
 

A buddy of mine gave me a tip on this but I won’t to know if this is normal. My receiver has some wobble in it. For an $800 GBB I figured that this wouldn’t be an issue. Is this normal?

Yes.

Roger that

I'll elaborate;

Depends on the batch, but some are REALLY stiff and some are not....try not to take upper/lower apart to often.

You can try a magic pin to prevent the wobble, but when you're in a game I highly doubt you notice it.