Home Forums Hunting & Shooting AR and Tactical Rifles Failure to fire

I've got a RRA in 458 SOCOM that is giving me problems. Feeding the first round out of a magazine causes the rifle to have light hits on the primer and a failure to fire. When the bolt is manually withdrawn, sometimes the round is extracted but, more often, the loaded round remains in the chamber. I've tried everything to get the initial round to slam home and function properly, but it's to no avail.

The reloaded ammo is checked with a chamber gauge and fits perfectly so it's being properly resized. Also, all subsequent rounds that self-feed from the magazine feed-fire-eject normally. Why is it that the first round just refuses to fully chamber and often doesn't have the extractor slip over the case rim?

Are you feeding the first round by with drawing the charging handle and releasing or by locking bolt to rear and dropping with bolt release?

Was thinking the same thing. Pulling the bolt all the way to the rear as apposed to releasing from bolt lock may solve the issue. This is what is happening with the subsequent rounds, gas is pushing the bolt all the way to "full stop" to the rear. May want to go for a heftier buffer spring?

Some chamberings,in some mags,are VERY fhuqking tight when topped off. Due same,the first round of a drum tight mag,takes significantly more ass to strip from feed lips,travel the ramp and get buried in the chamber. It is often "MAGICAL" to simply drive same,less that "extra" too tight round. Hint..................

Yep. That is the other reason I ran 29rds "down range". The other being that I could reliably hit a "Tac reload". Drum tight mags don't seat well against a closed bolt.

Yep. That is the other reason I ran 29rds "down range". The other being that I could reliably hit a "Tac reload". Drum tight mags don't seat well against a closed bolt.

If you download by one round, does the problem still happen?

The last time somebody mentioned this same problem they had 31 rounds in their msg (5.56).

I'm using 3 458 SOCOM rounds in a factory PM Mag-10 (.223) magazine. It could hold more. I have a NY compliant 458 mag that holds 10 (ordinarily holds 20 .223) which does the same thing when loaded with 3 rounds of 458.
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I've tried loading the first round both ways; bolt locked back with inserted mag then press bolt release button AND insert loaded mag with bolt closed and yanking the charging handle rearward and letting it go to achieve the maximum of forward bolt thrust. The fat ass rounds just don't cooperate.

When the extractor is not over the case rim, I would assume that the bolt isn't in full battery. But the rifle will drop the hammer which I thought couldn't happen when it's not in battery. I get very light hits but the hammer is dropping when I pull the trigger.

Does it have an O-ring around the extractor spring? If so remove it.

If memory serves me, it does have a tiny O ring there. I'll have to check. Isn't it needed?

It was added to the M4 carbine gassed guns. It’s become so notable that you’ll likely find one in every BCG out there. Except Colt, they came up with the idea but now use a proper 5 coil extractor spring.

There have been reports of problems occurring. Possibly an O-ring added to a proper strength spring won’t let the extractor snap over the case. Doubly so if your buffer spring is weak or buffer too light.
Similar to too much extractor tension on a 1911.

Mainly just throwing an idea out there.

For whatever it's worth, SOLGW BCG's do not have an O-ring.

That's good to know. Pretty sure my Sionics BCG didn't have an O-ring either but my newest Toolcraft did.

It's not always a bad thing but shows who's paying attention. And when paired with the right spring, it's not a bad deal but so many think that it has to be in there no matter which spring is in it. I've got some HD spring kits from BCM which are I believe Springco from years back that have the O-ring and supposedly the 5 coil spring but at the time, it wasn't known to be a bad thing. I've got a few from Colt that just include the 5 coil copper colored spring and black insert.

Maybe your chamber is out of spec.

Some will have an insert inside the spring, so with have the O-ring on the outside of the spring, some will have both.
Best practice is considered to have one or the other, but usually not both.

Best practice is to have a good spring and no O-ring.

I’ve never seen a kit without the insert. Blue for rifle gas and black for carbine. The O-ring was only meant for carbine gassed guns with the old spring.

I've been shooting and reloading for 40+ years but I'm rather new to the AR platform. I grabbed an AR before the nice governor outlawed them here in NY.
I shoot fairly stout loads (but within specs) and wouldn't mind trying a heavier buffer spring. I'm using a full factory RRA 458 SOCOM upper on a factory RRA Predator Pursuit (.223) rifle.
What would the next stiffer spring be? Where should I order one?

Assuming your lower has a carbine length buffer tube, if you want to try a heavier buffer spring, Sprinco makes an extra power one.


https://www.primaryarms.com/sprinco-m4-ar15-carbine-red-extra-power-carbine-buffer-spring