I may attempt to move the gas port to +1 and see if it quits.
I am not a gunsmith by any stretch of the imagination no matter how much my Fudd friends who only shoot shotguns and bolt guns are "amazed" that I can "build" an AR.
That said, this is where I'm headed on my journey to eliminate blown primers and ripped rims from the SFAR.
I am currently on the path of polishing the chamber to reduce case sticktion. This, in my mind, raises the risk of early unlock. This will also maybe put more pressure on the bolt while it's locked having less grabtracktion between the brass and the chamber wall.
To counter the early unlock after polishing the only tool I have, that I know about, is reducing gas down the tube and, maybe, a heavier buffer
Reducing gas down the tube to mitigate the early unlock due to polishing means, I'm guessing, increasing the potential for cycling problems due to not enough energy potential to compress the SFAR spring enough to lock back the bolt and/or pick up the next round so it seems a lighter spring is required. Since the SFAR bolt is about the same weight as a AR-15 bolt this seems, in my imagination, to be a rational line of thinking so I don't see why I can't switch to a standard rifle spring ... I *think* a standard carbine spring will be too short and weak.
My goal is a standard rifle spring with a carbine or H1 buffer. I've already tried the SFAR spring and a DPMS spring (slightly lighter) with both a H2 and a H3-ish buffer but the results were less than impressive.
The question that pops up after that is whether or not a lighter spring will be strong enough or fast enough to properly drive the next round into the chamber. Again, in my limited capacity of gunsmithing, I don't see why not although it may also reduce the top potential for rate of cycling that I might experience some issues with mag dumps, which I don't care about as long as it cycles for reasonably quick follow up shots.
Feel free to tell me where I'm wrong.
mdws.forumchitchat.com 
