Kimber45 3 Posted April 9, 2016 Hello all.this shout out is to all you 308/DPS guys and gals. First a quick rundown of my 308 build. Aero Precision M5 upper and lower. Mega Arms 16 inch mid length gas barrel cut down to 14.5 capped with an AAC brake. SLR Sentry 7 adjustable gas block. KAK duel ejector BCG. Geissele S3G trigger. Slashes Heavy Buffers XH carbine buffer and spring. Ok so out at the range today loaded up 1 round of PMC 148 gr. ball ammo in a gen 3 Pmag. Closed the gas all the way off and as expected the rifle fired but did not cycle.another round and another click on the gas block. Same result. After a few tries I was able to get the rounds to eject but the first shot the rounds would eject to 3 o'clock the second would just kinda drop at my feet also the bold wasn't locking back on the last round. So more gas... well that's when it happened. The set screw that adjusts the gas block crumbled into 3 pieces. WTF. I could no longer adjust the gas block the screw was fubar. So I am done for the day..... while looking over my failed attempt at a 308 build I noticed that the gas block screw was out quite far which also raised an eyebrow.Should I have to open that gas port open that far? Anyhow my thoughts are 1 low powered ammo. 2 too heavy of a buffer and spring.3 didn't have enough time adjusting the gas system before the malfunction. By the way contacted SLR they will be sending the replacement gas block by Weds.Sorry for being so long winded and if I missed anything sorry. Thanks for all the help.... Quote Share this post Link to post Share on other sites
NYMetsFan86 9 Posted April 9, 2016 glad they are replacing your gas block. you have to check again after the block, I have an XH buffer from heavybuffers in my 16" and its fine so trouleshoot again after new block. Make sure the block is lined up well with the port. Hope the new block does the trick for you bud. 14.5? thats a serious boomer right there haha Quote Share this post Link to post Share on other sites
Danno 127 Posted April 9, 2016 I had the same problem when I changed out my stock to a Magpul PSR. I put in a new spring and buffer (spring was much heavier) and it would fire but not cycle. I put the old spring in and the problem vanished. Try a lighter or shorten the spring you have. I would go in 1/2 inch increments on the shortening. Hope this helps. Quote Share this post Link to post Share on other sites
MidwestPX 172 Posted April 9, 2016 This thread may be of some help: http://www.njgunforums.com/forum/index.php/topic/75662-my-experiences-building-308-ars-from-parts/ Quote Share this post Link to post Share on other sites
Kimber45 3 Posted April 10, 2016 Thanks guys. Ty. Great thread.So from everything I listed I should be on target. I will replace the SLR gas block as soon as it gets here and try again... I would post pics but I can't seem to figure it out... computer wiz I am not.... again thanks to all that responded and if you have any other in site please don't hesitate. Quote Share this post Link to post Share on other sites
