Help me before I give up on the Grendel altogether

[montana]

Yes the Faxon and Satern barrels have uppers that match their feed ramps.

Since you apparently didn't know the difference between the rifle, M-4 feed ramp barrels and uppers before, I will assume you now have that cleared up and understand the difference. There are many thoughts for polishing and shaping the receiver and barrel feed ramps but the main concern is cutting through the hard anodizing on the upper receiver. https://www.youtube.com/watch?v=Q1xw3ffy3No LRRPF52 posted a very worth while process on polishing the bolt, extractor and ejector. I have done this to all of my Grendel bolts.http://www.65grendel.com/forum/showthrea...g-pictures I would try this before anything else, if your barrel and upper receivers are matched correctly.

[LR1955]

And I will let guys who remember all of this or have done it take over. I do not like giving out bad information and I almost did.

LR55

[204 AR]

Late to the party here but if I understand correctly what you're describing sounds like the rim of the case is catching the square-ended ejector and not allowing it to pop up and square up with the chamber. I had this happen on my first 6mm Grendel. The solution is as simple as beveling or rounding the end of the ejector pin. Won't cost you a penny to try it.

[VASCAR2]

I posted a link to accurate shooter describing this type of malfunction and how to mod the ejector. This could be a combination of a gas/timing issue in conjunction to the ejector inhibiting the case head from seating into the bolt face.

[centerfire]

Sounds like gas and recoil systems. I'd start with one of the rifles and install an adjustable gas block and H2 buffer. Then adjust from there. Grendel and AR308 builds are pretty advanced and require specific troubleshooting. If you're not familiar with the systems a complete rifle from a reputable manufacture is the best solution.

[NugginFutz]

^ This, Pretty much. Knowing how to assemble an engine and knowing how to tune it is the difference between a garage project and transportation. Likewise, assembling an AR and getting it to shoot are two different things. Until you get them running, they are just a collection of expensive parts flying in close formation masquerading as a rifle.

[LRRPF52]

We don't know anywhere near enough about your components and assembly methods to start diagnosing your FTFeed.

Is the bolt presenting over the base of the cartridges, or is it behind them when you see the malfunction?

What is the gas system length and barrel length of each barrel, and what are the gas port diameters?

How did you install the gas blocks?

So, I thought maybe I need to increase the reliability by running a VLTOR A5 stock system. So I installed it to replace the Carbine buffer. The FTFs are still happening.

Did you use the A5 buffer along with the A5 RET and spring?

It's interesting because in all my years of building these things, all of my builds run out of the gate, whether they be multiple samples of 16" MLGS, 20" RLGS, 18" MLGS, 22" RLGS, or 12" CLGS.

I do a lot of things to nip any potential malfunctions in the bud before the parts go into the guns though, learned over many years.

That Wolf 123gr SP ammo was the only ammo I had a malf with in my first 16" Grendel build.

[m1a convert]

Problem Solved. I put Spikes Heavy Buffers in both. 500 rounds of FMJ and a few boxes of Hornady 123 with no issues.

I will let you know if I run into issues again but I think the issue is solved.

Thanks for the help on this

[rabiddawg]

Problem Solved. I put Spikes Heavy Buffers in both. 500 rounds of FMJ and a few boxes of Hornady 123 with no issues.

I will let you know if I run into issues again but I think the issue is solved.

Thanks for the help on this

If your problem is solved, why are you selling your ammo?

[m1a convert]

I’m selling it because I’m going to shoot Hornady 123 gr in these builds.