DELETE

[WEST1157]

Not to get a new rifle but to diagnose and fix the problem with this one.

[neouser]

Sounds overgassed, causing a timing issue, but that's my answer for all 308 AR problems. This is my understanding of overgassing:

The gas pressure is driving the bolt carrier back and unlocking before the pressure has had time to drop. The case is expanded in the chamber and resists being extracted, and the extractor finally slips back over the rim after partial extraction and the bolt carrier moves back without the empty case. It moves forward and tries to feed the next round into the empty that's still halfway in the chamber.

[WEST1157]

hat exact "jam" are you having? If you tell us what the gun/cases were doing we OP what exact "jams" are you having, if you explain what exactly the cases/guns are doing we could better diagnose the issue.

To start, I'd say get non PPU ammo, I've noticed PPU ammo having a bigger case rim, also my LR308 ripped the rims off during my break in. (Used PPU brass on a few reloads). Try a different mag, and check your FSB like above. Also make sure it's plenty wet. 308 AR's have a lot of mass and like to be decently wet.

one casing was ejecting half way out and the other was half way in the chamber ,I had to drop the magazine to clear them both out. The empty casing was badly bent up.

[WEST1157]

Sounds overgassed, causing a timing issue, but that's my answer for all 308 AR problems. This is my understanding of overgassing:

The gas pressure is driving the bolt carrier back and unlocking before the pressure has had time to drop. The case is expanded in the chamber and resists being extracted, and the extractor finally slips back over the rim after partial extraction and the bolt carrier moves back without the empty case. It moves forward and tries to feed the next round into the empty that's still halfway in the chamber.

You got it this is the problem I'm having

[G21Shooter]

Clean, lube, and try different ammo.

[Mail Clerk]

Did you only use 1 magazine? If so, try it with a different magazine.

I ditto that suggestion. Wether it's metal or plastic the lips can be finicky.
In addition clean the area around the extractor and ejector well and oil.


Mail Clerk

[The War Wagon]

Yes. The moment you START shooting it.

[Mail Clerk]

one casing was ejecting half way out and the other was half way in the chamber ,I had to drop the magazine to clear them both out. The empty casing was badly bent up.

WEST1157,

The way you describe your delima it sounds like your chamber is dirty and the extractor is slipping off the rim. Before you next shooting secession re-clean the bore starting with the chamber first with a good solvent and brush it well!!!!

Too me it sounds like it's either the chamber is dirty OR your extractor and spring needs to be changed.

Mail Clerk

[Norcalkid]

When my BM XM15 (5.56) was new I had jams with steel ammo. IMO there is a break in period that you need to use good brass ammo in them. After 500 rounds or so steel worked with out issue in mine.

What ammo were you using?

[tiger222]

For some reason AR 308's (some). Need to be run very wet initially - frog lube is amazing btw. As the others have said try different ammo and mags. What is the rifle chamber for? 762 NATO or 308? Some will only shoot one, not the other reliably.

[SFCRangerDoc]

I would say mag issue first...usually I just lube and shoot the AR.

[Wallabing]

It's mostly the bolt carrier that has to be worn in to become smooth and get reliable..

The area where the bolt carrier rides on top of the hammer, and the bolt head and gas rings.

[Arnelcheeze]

the more you shoot it the looser it will get, but you may need to upgrade your extractor spring to a double unit from Sprinco, it could be slipping off from being over gassed.

[WEST1157]

Ok didn't shoot today but I think I found a deal on 308" at Turners PMC Bronze 147 gr 2780fps $14.99 I'm going to shot about 80rds through this on Sat and also Some 3 boxes American Eagle 150gr 2820fps ,I hope this breaks it in a little,If not back to bushmaster for them to diagnose and fix the problem.

[Danodog]

Ok didn't shoot today but I think I found a deal on 308" at Turners PMC Bronze 147 gr 2780fps $14.99 I'm going to shot about 80rds through this on Sat and also Some 3 boxes American Eagle 150gr 2820fps ,I hope this breaks it in a little,If not back to bushmaster for them to diagnose and fix the problem.

Hit the Walmarts around you to see if you can buy the ZQ1 7.62x51. $9.97 for a box of 20. A little over fifty cents a round. Some stores have it and some don't. It is hit and miss.