12.7" GB Range Report

[ClutchAutomatic]

Hello Horde,
So I was able to get out to the range to test the new group buy barrels out. Today I shot 35 rounds of Hornady then I followed with some reloads that were loaded from 29-30.8g of CFE223 using the 123gr ELD-M projectile.
Build spec: Seekins SP223 billet upper, Seekins MCSR V2 12" M-lok rail, Superlative arms low profile gas piston conversion kit, GB bolt, Dead air flash hider, and Silencerco omega suppressor. Eventually it will be a Seekins SBR lower.
I shot at 83 yards today and here are my results.




All my brass was scratched up today by this barrel.

[Bigs28]

39.8g of cfe seems high.

[ClutchAutomatic]

39.8g of cfe seems high.

that would be extremely high, I didn't go over 30.8.

[VASCAR2]

It’s got to be a typo, don’t think you could get 39 grains of CFE223 powder in a Grendel case and seat a bullet. Probably meant 30.8 grains of CFE 223.

The scratches on the brass case are probably from the feed lips and barrel extension. I hope you cleaned the barrel and chamber on your Faxon barrel before shooting. Some of the Faxon barrels need cleaned because debris/gunk is left in the chamber and bore from the QPQ/Nitride process.


If you didn’t clean the chamber that could account for some of the scratches.

I bet that Faxon’s accuracy will improve with use.

[ClutchAutomatic]

I cleaned the barrel with patches up and down a dozen times til it came out clean as I do with every barrel, not necessarily the chamber though. I'll see what I can do with cleaning it up some more or might have to bust out the Dremel haha.

[kpswihart]

Looks like a great build. No similar scratches from my bbl. Hope you get things figured out.

[ClutchAutomatic]

It looks like the barrel lugs have lips on it

[Tex Nomex]

It looks like the barrel lugs have lips on it
*image*

You mean on that 12 o'clock lug, on the chamber side? Hot loads can do that.

Curious about the asymmetrical lug wear. Little wear on the 2:00 lug, but huge gashes at 8:00 and 9:00.

How's your bolt look?
How much play when seating the barrel in the upper receiver?

[ClutchAutomatic]

You mean on that 12 o'clock lug, on the chamber side? Hot loads can do that.

Curious about the asymmetrical lug wear. Little wear on the 2:00 lug, but huge gashes at 8:00 and 9:00.

How's your bolt look?
How much play when seating the barrel in the upper receiver?

Bolt looks fine, the barrel pretty much snapped right in wasn't super tight or loose. The very first round shot out of the barrel was hornady black and it left the scoring marks that never went away after 85 shots.

[ClutchAutomatic]

here are the first 4 shots of hornady black out of the barrel with the flash on my camera

[VASCAR2]

The way the barrel extension looks I’m curious if the gas setting is correct being this uses a gas piston. Some times over gassed rifles will show exaggerated wear from being over gassed. I’ve never used a Superlative Arms gas piston system is there a gas regulator with this design?


Did you lap the front of the receiver to ensure the receiver is square. The wear on the barrel extension does not look even.

[ClutchAutomatic]

The way the barrel extension looks I’m curious if the gas setting is correct being this uses a gas piston. Some times over gassed rifles will show exaggerated wear from being over gassed. I’ve never used a Superlative Arms gas piston system is there a gas regulator with this design?


Did you lap the front of the receiver to ensure the receiver is square. The wear on the barrel extension does not look even.

The piston system has a bleed off and it was closed for the first few shots and I was having to mortar the rounds out as you can see from the brass picture. I've never lapped a receiver in my past 10 ar's though. About 10 rounds in I had it opened up all the wau and it was ejecting fine no failures just the brass scored. Does it seem like a qc issue?

[VASCAR2]

I’m not qualified to answer that but I’ve seen accounts of bolt failures because the receiver face was not square. In many instances parts will wear together to a certain point then stop. If the barrel extension is not square with the bolt I could imagine this type of wear might occur.

[BCHunter]

If looks like the barrel extension is damaged on the inner right side of all lugs. Did you use a ransom type rod during assembly? If so how much torque did you apply?

[Tex Nomex]

If looks like the barrel extension is damaged on the inner right side of all lugs. Did you use a ransom type rod during assembly? If so how much torque did you apply?

Hurting my brain. Wouldn't a rod gouge the left side of the lugs?