Wangbadan
Big Wang
- Jul 15, 2021
- 85
Hi all, hoping someone can help me troubleshoot this issue. Just built a 300 blk AR pistol but the problem I’m having is I can’t seem to chamber a round from the closed bolt position by hand, ie: combat reloads.
It only feeds the first round reliably when using the bolt release AND brass ammo AND the first round is on the right side of the stack. Subsequent rounds are cycled ok while firing so I don’t think it’s short stroking. It’s a bitch trying to chamber the first round of steel case. Have to bang the mag on my foot a bunch and make sure it’s seated just right.
I only shot about 30-40 rounds of supers through it so far. I’ve tried sellier and bellot 147gr fmj (brass) and 145 gr wolf (steel case). It seems to like brass better and prefer to feed from the right side of the stack in both usgi and pmag gen3 mags. Empty mags hold bolt open reliably. Don’t have any 300blk specific mags but I’ll get some and try those next.
It also doesn’t extract live rounds sometimes. I’ll release the mag and pull the charging handle but find that the round is still in the chamber sometimes and have to prod it out with a rod.
Here’s the build:
-BCA 7.5” barrel 1:8 parkerized
-pistol length gas tube, .750 low profile gas block
-Anderson upper w forward assist
-17D lower with mil spec lpk
-mil spec CH and nitride BCG
-pistol buffer tube with 3oz buffer
TLDR:
-gun doesn’t feed well
-hard to extract live rounds
-me sad
Thanks
-big Wang
It only feeds the first round reliably when using the bolt release AND brass ammo AND the first round is on the right side of the stack. Subsequent rounds are cycled ok while firing so I don’t think it’s short stroking. It’s a bitch trying to chamber the first round of steel case. Have to bang the mag on my foot a bunch and make sure it’s seated just right.
I only shot about 30-40 rounds of supers through it so far. I’ve tried sellier and bellot 147gr fmj (brass) and 145 gr wolf (steel case). It seems to like brass better and prefer to feed from the right side of the stack in both usgi and pmag gen3 mags. Empty mags hold bolt open reliably. Don’t have any 300blk specific mags but I’ll get some and try those next.
It also doesn’t extract live rounds sometimes. I’ll release the mag and pull the charging handle but find that the round is still in the chamber sometimes and have to prod it out with a rod.
Here’s the build:
-BCA 7.5” barrel 1:8 parkerized
-pistol length gas tube, .750 low profile gas block
-Anderson upper w forward assist
-17D lower with mil spec lpk
-mil spec CH and nitride BCG
-pistol buffer tube with 3oz buffer
TLDR:
-gun doesn’t feed well
-hard to extract live rounds
-me sad
Thanks
-big Wang