jamesp15
Active Member
A few weeks ago I built an AR10/LR308 (not sure which to call it lol) with the following major parts:
Aero Precision M5E1 Upper and Lower
Faxon Match Series 18" Fluted barrel (Link) (Originally 20" but when Faxon swapped the barrel I asked for the shorter, it looks better aesthetically to me.)
Faxon .308 BCG (and paid for their match/headspace service) (Link)
Odin Works Adjustable Gas Block (Link)
Aero Precision Upper and Lower completion kits for M5
Aero Precision M5 .308 Rifle Length Buffer kit 5.6oz Buffer(Link) (Was originally a carbine with 3.8oz buffer)
Giessele SSA-E Trigger
Magpul PRS Gen3 stock and MOE+ Grip
Midwest Industries Hand Guard (Link)
Lantac Dragon 7.62 Muzzle Break
Tried 4 types of ammo:
Federal Premium .308 165gr
Hornady SST .308 150gr
Federal 7.62x51 150gr (XM80CBL I believe is the box label)
PMC Bronze 7.62x51 147gr
On ALL of them 85 times out of 90 shots the spent casing will NOT Extract (still in the chamber, though not "stuck")
A very light tap with cleaning rod down barrel and they come right out, or if I close the bolt and manually cycle it they will extract 100% of the time, also a very light tap of the stock on the ground with the barrel pointing up and the cartridge will come out.
The spent cartridges have cuts/marks where the extractor tried to grab it. The ones that happen to extract pretty much fall out onto the table right next to me.
A friend suggested that it was over gassed and I have adjusted the gas block to all of its possible detent settings. (from all the way closed to all the way open, first 6 detents of the adjustment from closed and it doesnt cycle the action enough to hold open on empty magazine, 7th detent and up it will hold open on empty)
Any suggestions on what to try next?
Aero Precision M5E1 Upper and Lower
Faxon Match Series 18" Fluted barrel (Link) (Originally 20" but when Faxon swapped the barrel I asked for the shorter, it looks better aesthetically to me.)
Faxon .308 BCG (and paid for their match/headspace service) (Link)
Odin Works Adjustable Gas Block (Link)
Aero Precision Upper and Lower completion kits for M5
Aero Precision M5 .308 Rifle Length Buffer kit 5.6oz Buffer(Link) (Was originally a carbine with 3.8oz buffer)
Giessele SSA-E Trigger
Magpul PRS Gen3 stock and MOE+ Grip
Midwest Industries Hand Guard (Link)
Lantac Dragon 7.62 Muzzle Break
Tried 4 types of ammo:
Federal Premium .308 165gr
Hornady SST .308 150gr
Federal 7.62x51 150gr (XM80CBL I believe is the box label)
PMC Bronze 7.62x51 147gr
On ALL of them 85 times out of 90 shots the spent casing will NOT Extract (still in the chamber, though not "stuck")
A very light tap with cleaning rod down barrel and they come right out, or if I close the bolt and manually cycle it they will extract 100% of the time, also a very light tap of the stock on the ground with the barrel pointing up and the cartridge will come out.
The spent cartridges have cuts/marks where the extractor tried to grab it. The ones that happen to extract pretty much fall out onto the table right next to me.
A friend suggested that it was over gassed and I have adjusted the gas block to all of its possible detent settings. (from all the way closed to all the way open, first 6 detents of the adjustment from closed and it doesnt cycle the action enough to hold open on empty magazine, 7th detent and up it will hold open on empty)
Any suggestions on what to try next?
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