I'm hoping you guys can help me out here since no one, including Lage, can seem to get my gun to run.

I have an M11A1 (.380) that runs like a top with the factory upper. Zytel mags, Zytel mags with the reinforced lips, Shockwave Z-mags, everything works great.

But, my Lage Max11A1 upper refuses to run. I can get nothing more than single shots out of it. The bolt will barely even bounce after firing the round. It doesn't even come far enough back to extract the empty case. To pinpoint that it was my upper that is the problem, I did some swapping with my buddy who has the exact same setup as I do. His Max11 works on my lower just fine and my Max11 won't run on his lower. I've tried all the combos of mags above. I've sent the upper back to Lage once and they told me they replaced the bolt and test fired it before returning it to me. It contnues to single shit on every shot.

I am beyond frustrated and need help.

Thanks.

Have you asked over at uzitalk? Those guys are excellent. To be honest I wouldn't be surprised if Richard would just replace your upper for a new one.  It sounds like something is out of spec. Richard has great customer service. I'd just let him know your frustrations and see if he will just swap for another upper.

This go to the Mac section on uzitalk.

Call Jackie at Lage, MFG and ask if you can send your lower and upper into them for trouble shooting.

The Lage parts are machined properly and "in spec."

Mac lowers are all over the place in terms of their dimensions and basically crap.