09-27-2011, 02:18 PM
28" Krieger barrel with gas hole in barrel about .090. Gas block extended 2 inches further out barrel. Mega milled upper with Young Manufacturing side charging bolt carrier. Gas block is JP adjustable. Stock is rifle length with stock spring and 150 gram buffer. Using 28.5 grains 8208 with 123 AMAX.
Took to range 2 weeks ago to break in barrel with the old one and clean. Figured I would have to adjust gas block. The best I could get was for the bolt to catch on the empty magazine about 3/4 open. Could not get to lock by the bolt catch except by hand with empty mag. At this time I had a lite buffer and heavy spring.
Went and bought heavy buffer and stock spring and went to range last week to try again. Same problem and same result. Took to gun smith and we checked everything out. Even changed gas block to the one that came with the barrel from Krieger. He has a gun range so we could fire after any change. We tried several combinations of spings and buffers and the results varied from short stroke to the bolt catching on the mag. Never got but a few clean ejections and never ejected and feed a new round. Can turn gas down and hand eject brass and then release and it loads just cannot get gas system correct.
He was busy so I came home and got on line to research gas systems. Took rifle apart and checked everything from the alignment of the gas block,gas tube blockage, gas tube to gas key alignment, gas key to bolt holder, to the washers on the bolt. Could not find a problem. Would figure that the gas hole in the barrel at .090 would be enough but now I am starting to wonder.
Any other ideas? Thanks.
Took to range 2 weeks ago to break in barrel with the old one and clean. Figured I would have to adjust gas block. The best I could get was for the bolt to catch on the empty magazine about 3/4 open. Could not get to lock by the bolt catch except by hand with empty mag. At this time I had a lite buffer and heavy spring.
Went and bought heavy buffer and stock spring and went to range last week to try again. Same problem and same result. Took to gun smith and we checked everything out. Even changed gas block to the one that came with the barrel from Krieger. He has a gun range so we could fire after any change. We tried several combinations of spings and buffers and the results varied from short stroke to the bolt catching on the mag. Never got but a few clean ejections and never ejected and feed a new round. Can turn gas down and hand eject brass and then release and it loads just cannot get gas system correct.
He was busy so I came home and got on line to research gas systems. Took rifle apart and checked everything from the alignment of the gas block,gas tube blockage, gas tube to gas key alignment, gas key to bolt holder, to the washers on the bolt. Could not find a problem. Would figure that the gas hole in the barrel at .090 would be enough but now I am starting to wonder.
Any other ideas? Thanks.