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    Front Range, Colorado

Elmer75's Achievements

  1. Thanks for your input. I'll drill out the gas port first thing. I had a feeling.... The buffer and buffer tube came from 2 different sources, so I don't thing there was any compensation going on. Thanks for the spring recommendations, I just ordered a genuine Armalite EA-1095 spring. It should be here next week. It's always a bit tricky trying to figure out which parts I really need. Mil Spec has some real advantages. I copy you on mis-matched uppers and lowers. I got lucky, these two actually play together very well. I waited for months for the right ones to be in stock, and Biden was making noises in the background, so I figured I better get something before I couldn't get anything. I have an Accu-wedge in the lower which tightens everything up very nicely, with only the slightest gap between upper and lower. I'm happy with it. The FSB is wide open. I'll post a picture once I get the rifle put back together. Thanks again.
  2. Hey All, This is my first post on the 308 forum, but I've been reading here for almost a year. It all started with an innocent 80% AR15 project back in early 2020, which morphed into "needing more". One thing led to another, and one day I found myself machining an 80% AR308 DPMS lower. I knew then that I had a problem. At the time AR parts were pretty hard to find, prices were high, and I bought what I could find. The 308 went together pretty well, but I'm having failure to feed issues with my setup. Here's what I have: CBC 18" barrel with mid-length gas. Gas port is 0.070" CBC supplied BCG (make unknown) 5D Tactical 80% DPMS lower Daytona Tactical DPMS upper (5D Tactical uppers weren't available at the time) 5.4 oz buffer, 5.25" long, and has a loose weight inside the buffer 308 buffer spring from ?? A2 buffer tube, 9.75" inside length JP Enterprises adjustable gas block/FSB Mid length gas tube that ends right in the middle of the bolt cam notch Barrel nut tightened to 45 ft lbs I'm firing American Marksman 147gr M80 ammo. Groupings are consistent at 100yds. As far as I can tell everything is set up well. The gas tube ends where it's supposed to. The adjustable FSB is wide open, and the gas ports are lined up right. The gas tube is clean and clear. The bolt key engages the gas tube well. But the BCG barely moves after a round is fired. Once in a while it will start to eject the shell, but always hangs up in the chamber. I haven't once had a clean feed. My gut tells me the gas port is too small. There is very little gas residue inside the upper or the bolt after 30 rounds. If the problem is the gas port, I have no idea how large to make it. I read the Forum article on Barrel Gas Port Size, but there is very little info on 18" mid-length barrels. What little there is makes me think my gas port is too small. I appreciate any feedback you care to offer.
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