Filter

Real gunsmiths chime in.

To the professionals out there, not the shade tree guys like myself, y'all tell me if I'm on the right track.

Some time ago I built myself my first rifle. Trued up my action to the best of my abilities and chambered my first barrel. It shoots pretty decent. Half moa is the norm with minimal load development, and it's shot a few in the. 3xx range.

The problem is, when I chambered it I got some reamer chatter toward the end of the chambering process, and I failed to notice it until I test fired it. It's very minimal, but you can feel it in the fired cases. And you can see it in the chamber now that it has a few hundred rounds on it. Probably more like 5-600.

But it shoots good so why mess with it? Well, #1 its not right, and it's bugged me since day one. And I think it's probably going to lead to erosion in the neck due to it not sealing like it should when fired. And #2, probably the main reason, I want to learn how to fix my mistake.

So here's where I'm at. Long ago, the smith that used to due my work for me, may he rest in peace, had told me he had one chatter one time. He had called brownells and was talking to them about it and they told him a process to follow to get it to clean up.

He said brownells told him to take a cotton/flannel cleaning patch and fold it in half and make a small cut with a pair of scissors in the middle, and to slide it over the reamer to the neck/shoulder junction and take a light cut. Repeat the process until it cleaned up. He said he only had to do it once. I forget the depth of cut he said he took.

So that's where I'm at. Am I headed down the right path ? What spindle speed should i run ? I'm here to learn, feel free to tell me if I'm screwing up or if there's another way I should go about it please let me know.

I already moved the shoulder, the breach face, and the bolt recess forward .062" and my witness mark on the barrel and reciever lined up perfect.

Also, I picked up a reamer stop off of LRH, and before I moved the shoulder and everything forward, I slid the reamer in and adjusted the stop to the breach face. Then I added .005" just to make sure I didn't go too deep.

Here's the setup.
20250423_194828.jpg

Which Heavy Duty Truck?

No gears in the cp4.

Additive doesn’t seem to make a difference. Some run it religiously and they fail early and some never run it and have no problems for 100s of 1000s of miles. They’re simply a gamble. I saw one the other day that failed with less than 300 miles on it. My dcr has been good so far. But my cp4 had 218k on it. One little wear line on one of the lifter rollers was all you could see. Rest looked great.
I refuse to say that a fuel pump has a cam..so I will keep them gears lol
  • Like
Reactions: Geno C.

Criterion barrel brass pressure signs

Im curious if the OP sent the barrel in and what Criterion said. I just installed a 16” mid gas criterion core 223 wylde barrel (with a headspaced bcm bolt) on a bcm blem upper and KAK handguard (with a non adjustable badger ordinance gas block). When I checked headspace with the stripped bolt it was really tight (didn’t close on 1.4646 and barely closed on 1.4636).

I only have about 140 rounds through it (mainly BH 77 OTM factory ammo and various handloads with 77smk’s) and the accuracy at 100 yds has been disappointing. Getting 2-3” 10 round groups while my 5.56 nato 14.5” super duty will easily get me sub moa 10 shot groups. Not sure what is causing the issues but I removed and reinstalled the barrel nut to make sure it has clearance for the gas tube, the way it was timed in my initial install the nut had some contact with the tube. I will try different COAL on my handloads due to the slightly different freebore length in 223 wylde vs 556 chambers to see if that helps. I also removed the yhm phantom flash hider to get rid of as many variables on the barrel as possible. Working on another batch of 50 rds of handloads to see if these changes helped.

Im open to any other suggestions and ideas to troubleshoot accuracy issues. Could be that the barrel doesn’t like this combo of powder and bullet so im not ready to pull the barrel until I get more data with other powders and COAL.

Below is my target from my last range trip to test loads with 8208 xbr.

View attachment 8670915
That's disappointing for sure. I have a Criterion 16" Hybrid that is factory nitrided 416R stainless and it does really well with 23.3 - 23.5 grains of 8208 XBR and 77 SMK's. My COL is around or just under 2.250", this load shoots very consistently well 10 round groups for me in both the Criterion and a 16" Bartlein/LMT, my URGI is a little larger, but still good 1.1 - 1.4 MOA for 10 rounds.

Berger 73's are a little more accurate for me, those might be worth a shot.
  • Like
Reactions: WeR0206

6.5 Grendel

Unfortunately I’m realizing I haven’t even fired 100 rounds through this rifle so it was probably too early to do load development… but here’s what I got
1x fired Starline 6.5 Grendel brass
Shoulder bumped 0.004”
0.285 bushing for 0.004 neck tension
COAL 2.25”
Lehigh 110 grain match solids

H335 at 28, 28.3, and 28.6 all produced terrible groups.
Each would produce 3 rounds touching and then 2 flyers

TAC at 28, 28.3, and 28.6 grains
Only 28 grains produced acceptable 5 round group size of approximately 0.8 MOA.
Min 2398
Max 2437

Is that reasonable or should I try some other combinations to get higher velocity?
What's your barrel length? With 110s you should be getting much higher velocity.

Bartlein Barrels Update

Who gives a fuck! One dude starts this bullshit and you guys keep at it. Bartlein is running great as it has been for years. Its putting out great products as fast as it can and continuing to run as it has to make it successful. It’s not changing to some nuclear power plant worker’s whim because he thinks he knows better. No need to debate how business works. Has nothing to do with this post. Go to the pit and start a business post.

L3i New "Stinger" Barreled action

Maybe tolerances have changed , it has been almost 3 years ago , please read their experiences before saying anything to me

USMC Unertl locking in the parallax on the objective

Yes, if I push the cell slightly further into the objective housing, I can achieve a clear parallax free image at 300yds. I was contemplating the spacer Idea but after further review it doesn't seem feasible. Other than messing with the objective cell assembly, the only way I can see to fix it would be measuring how far the cell recesses in the objective housing when it is parallax free and taking X amount of material off of the end of objective housing, somewhere between 0.020"-0.040"