The Parts:
Standard H buffer and buffer spring inside a Bushmaster tube
Young Chrome Full Auto BCG (minus the bolt)
Superior Barrels 18" Terebratus barrel with matching bolt
(.223 Wylde Chamber, 1:8 male polygon rifling, M4 feed ramps, made from stainless and treated with hardblue)
YHM low pro gas block
Gas Tube from Bravo Company
Essential Arms lower with LPK from M and A Parts
The Problem:
I assembled it myself, completed a functions check, then took it to the range. I had basically put together a bolt action AR,
after every shot it would short stroke, sometimes it wouldn't extract the spent brass from chamber, other times it would go
as far as ejecting the spent brass and resetting the sear but not feeding a new round. After 20 rounds or so it became
harder and harder to cycle by hand to the point of (after clearing it) banging the stock against a table while a buddy pulled
the charging handle back. At that point I stopped and took it home.
After disassembling it I noticed the M4 feed ramps of upper receiver and barrel extension did not line up properly, I assume
I over torqued it putting the barrel nut on. They were misaligned enough to be noticeable by eye, if I had to guess I would say it
was off by about 3 degrees. I placed the upper in a vise and an armorers wrench on the flash hider to turn the barrel and line
up the feed ramps properly. Hoping that was the cause I went back to the range. It wasn't the short stroking continued.
This time at the range it was still short stroking but it was no longer difficult to cycle by hand, assuming it was from a lack of
pressure I put my suppressor on it and it worked as it should for over 100 rounds. When I took off the suppressor it was still
short stroking and I noticed a large build up of carbon on the barrel just forward of the gas block. I am using the correct diameter
gas block for my barrel, and the correct length gas tube, there is a roll pin in the block holding the tube in and I tightened the 2 set
screws as tight as I could, and used blue loctite, and the gas block is properly aligned with the barrel as best as I can tell.
What is the most likely cause of the short stroking? I noticed most other gas blocks do not have a hole all the way through them
like the YHM does, could this be the problem? Or is it likely caused by something I did during assembly? I could switch to a lighter
bolt carrier but I don't think I should have so much (or any) gas coming out of the gas block.
Thanks
ETA- I'll post pics of the carbon on the barrel when I can