98Z5V

Armalite AR-10 Carbine receiver extension is indeed 7 5/8" internal depth, and it does take carbine buffers that are 3.250" long. You want to make absolutely sure that the buffer is H3 weighted, at 5.4oz. The recoil spring is the Armalite EA1095 spring. Those are the exact parts that are in the kit that @dpete linked above.

Sorry to hear this, brother.

A rifle receiver extension is 9 11/16th" deep. On a .308AR, a rifle buffer is 5.200" long. The AR15 rifle buffer is 5.900" long. The AR15 Carbine H3 buffer is 3.250" long. You cannot use an AR15 rifle buffer, it's too long. You cannot use an AR15 Carbine buffer, it's too short. It will physically fit, and you will slam the hell out of your lower receiver, with the BCG, the first time you fire it.

...and ON THAT NOTE!!! Here's the best one...

Read this, man...

I was gonna bring you up. I didn't want to rip off that band-aid, though...

CMMG Banshee uses AR15 lowers, AND AR15 mags, with mag kits to convert the mags. I hate to tell Rob, but those things run like a striped-ass ape. We need to know more about the 9mm gun that this guy has, before we can make anymore recommendations, or critiques. Then give up all the deails on your 9mm. We cannot go forward with information, until you do that. Descriptions are mandatory, pics are almost necessary. Otherwise, we're just pissin' in the wind here, in this thread..

What are you posting here? All you did was quote 2 posts, and you didn't say anything. Go to the Intro Section, tell us about yourself. THEN go to the Build Section, and tell us what gun problems you have. Here's a link to the Intro Section: https://forum.308ar.com/forum/22-introductions/ Here's a link to the Build Section: https://forum.308ar.com/forum/47-building-a-308ar/ Go hit those two, in that order, and in the build section post that you make, tell us all these details, that we need to make a recommendation on your issues, over the internet, when only dealing with descriptions and words... Details are mandatory, if you want an accurate outcome from this... Check it: Thanks for reading, and hanging around long enough to read this. Your compliance is appreciated. Otherwise, it's nothing more than garbage-in, then garbage-out. Thanks for your understanding on the matter.

Gonna need details on the whole gun, just like we tell everyone else that states operational issues. Start by reading this - and comply with the details needed... YOU have to tell US what you have - so we know what we must work with. That, right there, is the very "step 1" in the whole process. Otherwise, it's just guess-work. Read this:

We were trying to diagnose a rifle problem, over the internet, based on a description of what was happening, by the shooter. What we ultimately had was a problem in the Fundamentals of Rifle Marksmanship, purely from the beginning, by the shooter. Entirely. I recommend this for a required reading list. And not just READING... UNDERSTAND IT, absorb it, and PRACTICE IT... then you can try your hand at Basic Rifle Markmanship. If you can find an old copy of the real Army FM 22-9, that'll do you good. That's the last one before it got crazy, and started new FM numbers. In the meantime, this one will do: https://www.amazon.com/Manual-3-22-9-Marksmanship-Weapons-February/dp/1475198299 Basic Shooting Fundamentals are FULLY covered in this manual. START with basic shooting fundamentals, before you request that we diagnose "gun problems" over the internet - make sure you can SHOOT, first. Then we'll talk...

Like Jim stated. Battery posts are lead. Most battery clamps are lead. Lead does very well conducting both amps and volts. Otherwise, car makers have been stupid as fuk for the last 100+ years. So have battery companies... Lead works quite well for conducting electricity. Well enough to work in all our vehicles, every single day.

Good. Pulling the ejector is easy without special tools, and it's super easy with .45 ACP cases. .The .45 ACP rim diameter is identical to .308 Win rim diameter, which means it fits the .308 bolt face perfectly. Put a used .45 case over the bolt tail to protect it, put another .45 case in the bolt face, in a vise, and tighten until it's all straightened up. Add a little twist to the vise handle then. You can then tap out the ejector roll pin easily, but you might have to brace the underside of the bolt, and hold it straight, while you tap out the roll pin. After the pin is out, relax tension on the vise, slowly, and remove the case that was in the bolt face, and you can take the ejector and spring right out of it. If you hit that roll pin like a Hero, you'll certainly knock the whole rigged-up assembly right out of the jaws of the bench vise. Just sayin'... P.S. DO NOT remove the extractor for this - it helps to hold the .45 case in place, while you're screwing everything down in the vise. Removing the extractor is not necessary, and will hinder the operation. This operation takes 3 hands to perform, when done properly, you'll see when you start it, so be patient. Slow is smooth, and smooth is fast... You don't need a hundred-dollar special tool to do it, though. Just a couple .45 cases and a vise. And a pin punch. P.P.S. If there's a bunch of brass shavings down in that hole, make sure you get a pic of it before you clean it out...

The amplification modes are cool - let you bump up what you hear, "normal voice" and such - but how far you amplify has zero effect on that they do for noise attenuation. They crush gunshot noise like no other electronic ear-pro I've ever used or had. I played with them at last month's shoot, different amp levels - still made the gunshot noise go away, no matter what the setting. Like I said - badass enough to buy a second pair, and I did.

Ryan Fugit is the guy that runs the Combat Story YT channel, and he has some great interviews. This one with Kris Paronto is one of the greatest ones. Pay real close attention near the end, from the 1:20 mark and on. I live this mantra. https://pages.e3association.com/conference-2021

6.5 Creedmoor gun? That's some great ammo, and their 147s are even better.

Rifle Recoil System? Carbine Recoil System? "Aero M5" has both. Yes, carbon fouling in order to form a gas seal is normal. How many rounds out of this gun so far? Total... These aren't AR15s...

Did you use headspace gauges and check this chamber before firing it? What ammo are you using? Headspace check is the NUMBER ONE THING that needs to be done on any large-frame AR build. Numero Uno. Second statement - an 18" midlenth gas gun with your barrel specifics needs 0.080"~0.085" gas port diameter, and I recommend the 0.085" end of that spectrum, to make it function correctly. That's WITH a proper recoil system. For a 16" barrel, 2" less dwell time, you will need 0.090"~0.095" - and I recommend the higher side of that range. Start smaller, try 0.090". Don't be surprised if it has to go up a little bit. 0.63" is nowhere close to what it needs to be, nowhere. Fix your recoil system first. Play with the barrel gas port later - or at the same time. Start 0.090" after you have the correct recoil system parts installed.

Make sure you lemme know what you think - I love mine enough to buy a second pair. 2 is 1, and 1 is none. Gotta have backups. Still planning 4-deep, too. P - Stealth 28 HTBT A - Stealth 28 HTBT backups C - Walker Silencer 2.0 E - Orange foamies...

That's normal, breaking in a gun. I HAVE seen brass shavings clog up an ejector before, so test that ejector, like I described above - make sure it's moving in and out smoothly, and not hanging up. It might be good just to remove it, and clean all that stuff out, and see what comes out... You shoot .45 ACP? Have any spent cases laying around?

I'm not sure yet - what changed from the first post above that I quoted? It was running, so what changed to make it start malfunctioning? Ejector or ejector spring break? Test them, to find out. Hook a spent case under the lip of the extractor, and push it straight inline with the BCG, and see if the ejector moves in and out smoothly. See if the extractor is hanging on to the case rim. We know the gas system and recoil system are good - it was working.

Correct. Fundamentals.

^^^ That's incredibly badass, right there...

I saw the title, and knew you'd be in here...

Damn right, brother!

That's a Failure to Eject. Focus on the things that make ejection happen. Gas system is a huge part, recoil system is a huge part. The Ejector and it's spring are the (obviously) biggest part of the function. To a limited degree, if the Extractor is messed up, it'll let go of the spent case before the Ejector can kick it out of the receiver. That's rare, though. That's definitely not a double-feed malfunction. Double Feeds are two live rounds trying to enter the chamber at the same time. Double Feeds are ALWAYS magazine related.