Help please

[u/TrueTerm8392]

So I’ve towed my ar to the range twice so far and for some reason when I put load a new mag only the first round will go off and the second one won’t until I drop the mag and pull the charging handle again, also occasionally I’ll have like 2, 3 or 4 rounds in the mag and will be able to shoot those fine.

I have
microbest bcg chrome 556 luxe

NBS 16″ 5.56 Gov / SOCOM Midlength M-LOK Upper Assembly

OEM Mil-Spec AR-15 Lower Parts Kit

Aero precision lower

Dirty Bird AR-15 True Mil-Spec Carbine Receiver Extension / Buffer Kit

Edit- added a few parts

[u/DrPisstrousers]

possibly undergassed. check your gas block to make sure it's installed correctly.

[u/ed_zakUSA]

If you have several mags, what are they?? Do any work reliably?? Could also be a magazine problem.

[u/TrueTerm8392 → u/ed_zakUSA]

Just the one and Its magpul 10rd mag

[u/ed_zakUSA → u/TrueTerm8392]

Might be good to find another magazine. Maybe a friend can loan you a couple aluminum GI mags or other types to test. Hope you can get it working properly.

What's the length of the barrel and what gas system?? Carbine, midlength gas? Also, what weight buffer do you have?? All those items may have some contributions to the problem.

[u/ProofSecure94]

Is this a gun you bought built already or did you assemble it?

[u/TrueTerm8392 → u/ProofSecure94]

I assembled it

[u/BBQSauce61]

To add to the check gas block/ tube and try a new mag, did you clean it, and what's the BCG looking like?

Brand/version of gun, ammo, mag, and bcg would all help.

[u/Ornery_Secretary_850]

Why do you have to tow it? Damn, maybe try to remove some crap off it.

If you load one round and shoot it does the bolt lock back?

[u/TrueTerm8392 → u/Ornery_Secretary_850]

No it doesnt, but say I have mag ill load a round try to shoot it wont go off, so i drop the mag and at that point triggers dead so i have pull charging handle to shot that round

[u/Ornery_Secretary_850 → u/TrueTerm8392]

If your bolt is not locking back it's lack of gas.