u/bigsexy133

So I took my MAT9K apart to do some investigating and the extractor on my new roller delayed bolt has a small lip and it appears to be preventing the casing from fully seating to the bolt and appears to be the reason the breach, bolt doesn't return to battery. In the pictures the roller delayed is on the left with lip and the second picture both have a round in but you can still see the casing on the roller delayed breach. Hard to see in the second picture but in person very noticeable

Any ideas

So I have now taken my radial delayed MAT9K to the range and it won't go back into battery after the first round. It only works on the first shot and its the same whether I use my AR9 Glock lower or AR15 Endomag lower. But when I clear it and start again only the first shot works and you can see the breach slightly open not fully back to battery? I have used all my different mags KCI, SGM, Magpul subsonic, supersonic, round nose, flatnose....three varieties of ammo Pistol Pete reloads, blazer 124, Remington flatnose. Both lowers and mags worked with my direct blowback MAT9K that broke. I will say that the spring seems way softer, easier to rack than my old blowback. Any suggestions