ar 15 cycling problems or False firing

[toddthedog]

I have an ar 15 with the nato 1:7 twist 20 inch barrel and a chromoly bolt but dont remeber the manufacture. the problem that im having is that when i shoot brass casings the gun cycles perfect for as many rounds as i want but when i put wolf steel casings it will fire, eject the round, cycles a new round but then when you pull the trigger it clicks but no fire and no impact from the firing pin. is the problem because the brass is 5.56 and the steel is 223 or what? im at a loose of words here. please ask any more questions about the gun and i will try to answer them at the best i can.

[rero360]

lots of guns don't like steel cased ammo, purely that. Some run fine with the steel cased ammo with the lacquer coating, some just the new polymer coating, some with both, some with just brass.

If you want to run steel cased ammo, you have to keep your chamber extra clean, and probably could benefit from getting your chambered polished a bit. even then, best to stick with brass.

[General Urko]

Hey Todd.
I've seen this before... especially with new rifles.
The fact that it chambers and fires the first steel case round is due to the initial full stroke charging spring pressure to lock it to fire, as opposed to the shorter cycling strokes that don't.
The reason it leaves no firing pin mark, is due to the bolt carrier not reaching full battery after cycling to fully rotate and lock the bolt closed to fire, which is a really good thing.. cause it would blow up if it were able to fire without it fully locked.
Two problems I would suspect are the steel case ammo for one, since brass works fine, but probable cause overall would be a dry action.
Are the carrier rails, bolt cam pin, and 1 drop for the gas rings, all oiled properly?
Never hurts to put a drop on the hammer where it drags under the carrier as well.
The steel case stuff isn't quite as slick as brass for a dry gun and would do this, but should work fine after a nice lube job for the action.
Always oil up the army toothbrush and dress out the bolt group so its wet but not dripping before use and it will run just fine with both kinds of ammo... plus it helps keep the crud from sticking so well when its time to clean.
So.. oil it up and give it a go.. well lubed actions always work better than dry ones.
5.56 AR's will also fire .223 no problem.
Enjoy!

[Time of Flight]

Hey dont double post. You were getting all the answers you needed in the other post you just made.