AWCY? Poison SuMac troubleshooting

Weltall

Recently built this drum-fed badass and while I love it, it has a tendency to fail to eject every 2-3 rounds. First Mac11 build, not sure what I should tweak and what I should leave alone. If anyone has any knowledge or insight I would appreciate it

stuab

How many rounds do you have through it so far? Is the upper well-oiled at all the friction points?

The most likely issue, though, is that drum mags are notorious for jamming. Have you tried a different brand of drum magazine?

Weltall

The drums were brand new, I cleaned a lubed them as well as I knew how. The upper has been lubed, 100ish rounds through it, disassembled then cleaned and lubed again. Put another 40ish rounds through it, same problem.

I saw a post on another site about adjusting the ejector rod in the Mac11 upper, I may try that next time I have a moment to fiddle with things.

I may also buy a coffin mag to try as well, or print one.

stuab

Weltall

You could also hit up @avesrails or @JC_Arms on Twitter. They both manufacture Mac11 uppers and would probably have solid insights.

Weltall

Solved the problem. Had to open up the ejection port a bit. There was extra printed material that was causing the brass to bounce back into the action. The SuMac runs like a top now!

stuab

Nice!