Line SI Promaster

[Axel]

Well, 20 minutes or so with a set of files and I've fixed my bolt stick issue. I should have gotten a picture first. It looked like the feedneck was rotated slightly on its central axis so that the two wings were sticking down into the bore instead of lining up with the tube of the barrel snub. And beyond that, the finish of the machines edges on the elbow look horribly chattered. I'm totally perplexed how this happened, because the gun was completely unfirable, but the condition and especially the breach wear indicates that this gun has seen some action. Would the feedneck unthread from its mount?

Anyway, the gun leaks like a sieve but I did get enough air pressure to confirm that blowback is functioning properly. Next step: rebuild with fresh seals.

Un2xs, what are these unobtainium parts you need?

[Axel]

So on further inspection, I figured out the bolt is getting torn up (and sticks) due to the RAGGEDY EDGE OF THE FEEDNECK STICKING DOWN INTO THE BORE. I'm honestly shocked at the workmanship. Mostly the gun seems exceedingly well built

While l figure that out, I also need a rebuild

[Axel]

No, but you inspired me to try tearing mine down again. It doesn't want to function, and I think it mostly needed a deep cleaning as well as a light deburring of the torn up bolt.

I discovered my detent spring is rusted through from years of sitting in paint gunk. Gonna try to fashion a replacement from a pen spring

[un2xs]

Do any of you have personal experience with Line SI Promasters? Do they require anything special regarding a service/rebuild? I have not torn mine down, but it's supposed to be complete.

EDIT: Rear Upper Bumper and Screw are missing.

I found the Pukin Dogs Promaster page, but have not digested it yet. https://pukindogspaintball.com/bg-guns/PROMAST.htm

These guns look to be fairly tunable, but may require unobtanium parts to sweet spot.