Extraction and feed problems

[buck119fa]

New to the forum and the 6.5, this is .my first build in this calaber. I've read a lot on here and fixed many issues. Thanks for all the tips.
Got the magzine issue fixed with the trimming of them so that is no loger a feeding issue. Working on over or under gas.
Problem is this...
Factory anderson 120g nosler function fine, 50 rounds not 1 issue. Average 2560fps thru the chrono. Bolt locks open as it should when mag is empty.
My Hand loads will stovepipe.... or pick up the next round but jam because the empty didn't fully extract 1 out of every 8 or so shots.
100g nosler, 28.3g of benchmark, new hornady brass. Average 2680fps. Bolt also locks open as it should when the mag is empty.
Im thinking over gassed? I've adjusted the gas block to about 1/2 closed off now and still getting the problem.
Build is a 20" grendel hunter upper, rifle length gas, grendel hunter bolt also, rifle lenght stock, buffer and Tubb flat buffer spring.

Thoughts?

[Popeye212]

What does it do on this chart.
22671928017_8c68eccc92_b.jpg

This helped me solve mine turned out to be the BCG. Hope this helps

[buck119fa]

According to that chart the factory ammo is perfect ejection. Hand loads are over gassed. Going to the range later(weater permitting). I'll try adjusting the gas down again and try both loads.
That. Chart is handy, Thanks

[Kswhitetails]

I preface the following with the fact that I experienced your same failures on my first build, and after finding this forum and reading a while have learned the following. I am no expert.

Where is your ejection pattern developing when you have successful ejections? It should be 330-4 o'clock.

Are you getting claw marks in the extractor groove of your cases? Have you tried rounding the face of your ejector, polishing the extractor claw, etc...? https://www.youtube.com/watch?v=kMrMUyyWV0k

Are you reloading the brass with which you had no issues, or are you using a different brand?

Do you know what your gas port size is?

I assume you started with your gas block wide open, and fired groups of rounds until failure at each adjustment going downward to 1/2 closed? I have always used the "from closed" method in setting my AGBs, which I find works better than going the other way. You want enough gas to operate your system without failure, any more (there is a window) and it starts to get spastic and harder to diagnose. There are a lot of variables involved here, gas port size, gas system length, gas block alignment, gas system seal, friction of the carrier in the receiver, spring tension, buffer weight, load, projectile, etc. You want to find the window your rifle functions well in after accounting for the many possible variables. The only real way to do that is to fire lots of rounds, from all your potential sources of ammunition, and ensure that the system is properly built.

Building with high quality components is the surest way to guarantee a big "window" with which to operate your system, allowing a greater range of variance in these variables without having to determine adjustments. The bigger the window, the more likely you are to have an all round well running rifle.

I have only used AGBs from ODIN, SLR, and on my Anderson Arms piston carbine. My process is to close the block down, fire to ensure no gas operation at all, then open a single turn. Then, loading 10 rounds, I fire and observe the ejection pattern until I get a failure. I then open another full turn, and repeat. At this point I'm usually able to find rather quickly a spot at which my rifle functions well, with ejection about the 330 position, and I will usually add another 1/3-1/2 turn. I will then switch to Wolf steel, and fire until failure, which so far has never been an issue. 1/40 rounds is my minimum standard in Grendel.

I put a lot of the info together after watching Johnny's video above. Hope this helps.

[VASCAR2]

Does the extractor move easily with thump pressure? I’d inspect the extractor and spring. On my 6.5 Grendel the extractor spring rides on a small cone. There are upgrade extractor kits that contain a small O ring plus you can get stronger extractor spring.

If the extractor has the O ring you might try shooting with it removed. If there is no O ring you might try adding the extractor O ring.

Adding or taking out the O ring on the extractor has cured similar failures in the past. Like Ksw mentioned I’d inspect your brass and make sure the extractor fits the rim of the brass.

[buck119fa]

Gas port is correct size, already pulled the gas block checked size and verified proper alignment and resealed. I did not skimp on parts for this build. Did that once on another build, never again. I'll look at the extractor directly and report what i find. Thanks

[buck119fa]

Checked the extractor, seemed ok, no deep marks on the brass. I did polish it to take off a little bit of sharpness. This doesn't have the o-ring on it so I'll take one with me to the range to run a test if need be. I'll run the gas check first. Thanks for the ideas

[buck119fa]

So... Just returned from the range. Ajusted the gas again and ended up 1.5 more tuns in, decreasing the gas. 50 rounds of hand loads not 1 hiccup, functioned correctly every round, still runs the factory stuff good too. Ejection is 330 to 4 oclock right where it should be. Not seeing any marks on the new brass from the extractor or mags. Seems to be running good now. I did cut down the front of the ACS mags 1/4 inch and that fixed the mag feed issue, with my elander mags i didnt need to cut the front down but i did cut 1.5 coils off the spring. The 4rnd mags hold 5 now and havent missed a beat feeding.
So far looks like my issues are resolved. Thanks for the assistance and ideas!

[Kswhitetails]

Very good to hear, sir! Welcome aboard, and stick with your new Rifle. Let us know how you find it as you progress.