Ammo suggestions.





#1
Fellas, I've have a 10.5" ar pistol and LC M855 ammo is having some issues, i.e. failure to extract. Just to test I used different mags and still the same issues. Next I ran some IMI M855, and that ammo ran like a champ. I suspect that the IMI ammo is loaded just a little hotter than the LC ammo. Looking for some range/plinking ammo hot enough to reliably work my ar pistol. It can be M193. What brand do you guys recommend?
 

Janizary

Geth Prime
Forum Supporter
2019 Supporter
#2
Questions:

  • Is the LC ammo factory, straight from a sealed box, or 2nd hand? (some resellers will pass off LC reloads as 'factory' and the cases may not have been sized properly which can cause extraction problems, or just underloaded to save on their costs)
Else,
  • Is this a factory or a custom build?
  • If custom, did you build it or someone else (shop, friend, etc.)
  • Do you know the gas port size? (or, who the OEM for the barrel is?)

I ask the above, because if all else is 'good' and functioning correctly, a properly-gassed 10.5 barrel with carbine gas port should run LC 855 with no problems. In fact, it should be somewhat over-gassed. All else good (properly lubed, gas-key staked, torqued and gasket sealed, etc.) I'd be looking at gas block alignment (or small chance of a under-sized gas port...BA Hanson/Premium like very skinny ports, for example).

LC factory ammo runs hotter than some other bulk ammo. If you are right on the edge of cycling with very hot ammo, I'd have concerns about operability.

With a properly-setup 10.5 upper you should be able to run lighter loads like PMC bronze and Armscor without any operability problems (and still be over-gassed).
 

iav8524

Member
Forum Supporter
2019 Supporter
#3
Questions:

  • Is the LC ammo factory, straight from a sealed box, or 2nd hand? (some resellers will pass off LC reloads as 'factory' and the cases may not have been sized properly which can cause extraction problems, or just underloaded to save on their costs)
Else,
  • Is this a factory or a custom build?
  • If custom, did you build it or someone else (shop, friend, etc.)
  • Do you know the gas port size? (or, who the OEM for the barrel is?)

I ask the above, because if all else is 'good' and functioning correctly, a properly-gassed 10.5 barrel with carbine gas port should run LC 855 with no problems. In fact, it should be somewhat over-gassed. All else good (properly lubed, gas-key staked, torqued and gasket sealed, etc.) I'd be looking at gas block alignment (or small chance of a under-sized gas port...BA Hanson/Premium like very skinny ports, for example).

LC factory ammo runs hotter than some other bulk ammo. If you are right on the edge of cycling with very hot ammo, I'd have concerns about operability.

With a properly-setup 10.5 upper you should be able to run lighter loads like PMC bronze and Armscor without any operability problems (and still be over-gassed).

THIS.. I have a 10.5" Bear creek upper with a carbine gas system on my SBR.. That thing, even with gun show reloads drops brass regularly at like 1-2:30 using the muzzle as 12:00. Now my Adams piston upper doesn't really like to run with .223 reloads, but will run 5.56 NATO ammo just fine.