Proof Barrel break in

WtxShooter

Gun loving dad!
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Feb 17, 2017
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Lubbock, TX
So I’ve recently purchased my first Proof barrel and paired it up with a Surgeon action. It’s chambered in 6.5 Creedmoor and I set this up for a primarily hunting rifle, then precision shooting after. My question is, how many rounds are you guys typically seeing before your groups get respectable? I have had 3 other rifles made or rebarreled, (2 in 6.5 Creedmoor, 1 in 6mm Creedmoor), and they’ve at least had sub-MOA grouping within the first 50 rounds. This particular rifle, however, is not good at all. Best 5 shot group is 1.27” after 50 rounds. 20 rounds of Hornady 140 grain A-Max, 30 rounds of Prime 130 grain. The Hornady had the better groups, but the Prime had the best velocity and the better SD. Just curious if I should start to worry, or give it more time. Any input is GREATLY appreciated.
 

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What barrel length is that and it's that mardi gras molded color?
Ha! No, that’d be a salt Camo from Core. And it’s a 20” barrel that is exclusively shot suppressed. As far as the Smith is concerned, that’s my concern. He’s new to me, but was highly recommended by a few of my friends. So I’m gonna give it a bit, and then approaching that issue.
 
It should shoot from round number one. Have you tried it unsuppressed? Have you measured any fired brass to compare with virgin. Do you have a concentricity gauge to check the run-out on the fired brass?
 
- Take the action screws out and put them back in at whatever your required/desired in/lb torque is; also make sure nothing weird is going on with the stock/action/bottom metal fit
- Shoot it without the suppressor; some suppressor/barrel/barrel length combinatrions have totally fucked the harmonics of a gun up before
- Put the optic from one of your known sub MOA guns on this one and shoot
- Check the crown with a flashlight as best you can
- Measure where the lands are; for all you know you're jumping the bullet 5 times longer than you should be, etc
- Check to make sure the barrel is actually free floating
- Check the usual things everyone usually checks but it can be that anyways; scope rings, mount, etc
 
It should shoot know loads decently(some good groups<1") in the first hundred. I definitely see barrels speed up after 200-250 rounds. Maybe you should pick up a couple of different boxes of bullet manufacturer.

I've started to think you should't even chrono or have any expectations in that first 250. Then start load development. Or just shoot factory ammo.

I don't think that is the norm around here. If it was 6mm CM i'd be a little more worried, with the short barrel life.

Barrels are made in factories, NOT heaven!

Lemons do exist. You could contact proof first(Bad run?), then gunsmith second.

Are you a Sub-MOA shooter? I know I have good days and bad days as well. I always bring along a proven one-hole rimfire with me to get warmed up with at 50y. If i'm shooting good groups with the 22LR or 22WMR than its the rifle.

The German has quite a few valid points. Thats just a starting point.

On another note. Light rifles don't tend to shoot to well! Manners carbon stock? What does the rifle weigh? Do you have a Atlas bipod you could use?
 
So you guys think threading a barrel can't affect accuracy?

That wasn’t what you wrote. You wrote that it would take a certain number of rounds for it to come alive(due to being threaded alone), which is completely false. A poorly cut thread will not affect accuracy by itself. Screwing a muzzle brake onto a poorly cut thread certainly can though.
 
To the OP. The only things that I can discern by looking at your photos is: Scope is really high above barrel (mount) and your harris is unusually high below your stock. What's going on with the bipod mount? This is just knit picking.
 
Looks like the gunsmith threaded the "dingus". I don't know what effect that would have on accuracy, if any, but Proof has a sticker that comes on these barrels from the factory that say to cut the skinny portion on the muzzle end off. It's an artifact of the carbon winding process.

I would try without the brake, if that doesn't work I'd have it crowned/rethreaded how it's supposed to be (maybe by a different guy???).

My Proof 6.5 SAUM was throwing good groups right off the bat.
 
Looks like the gunsmith threaded the "dingus". I don't know what effect that would have on accuracy, if any, but Proof has a sticker that comes on these barrels from the factory that say to cut the skinny portion on the muzzle end off. It's an artifact of the carbon winding process.

Ouch! I would not be happy about that....
 
I'm inclined to agree with Ledzep. Your barrel seems to have an awful lot of metal at the muzzle end compared to many of the Proof barrels I've seen here and elsewhere. I'd see if your Smith (or perhaps Proof if they'll cut and thread) can cut back and re-thread the muzzle.

Please post results once you get sorted. I'm curious about cause of your groups opening up.
 
Looks like the gunsmith threaded the "dingus". I don't know what effect that would have on accuracy, if any, but Proof has a sticker that comes on these barrels from the factory that say to cut the skinny portion on the muzzle end off. It's an artifact of the carbon winding process.
I didn't even notice that before you mentioned it but I think you're right. When I put my muzzle brake on the end of my Proof, there's hardly more than 0.5" of steel showing. It's a Heathen brake so slightly different but still.

If so, OP may want to let that gunsmith know. Proof barrels sometimes get a bad rap from people who had their gun put together by a gunsmith who isn't experienced with carbon fiber barrels.
 
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The culprit may be the threaded dingus, but, I have a 22” Proof Sendero 6.5CM, with no dingus, that took 80 rounds to settle down. Went from ~1.2 moa to 0.48 moa over the course of too many rounds. Very frustrating but it now shoots pretty good. If I had it to do over I would have run 100 Prime 130 through before doing load development.
 
So I’ve recently purchased my first Proof barrel and paired it up with a Surgeon action. It’s chambered in 6.5 Creedmoor and I set this up for a primarily hunting rifle, then precision shooting after. My question is, how many rounds are you guys typically seeing before your groups get respectable? I have had 3 other rifles made or rebarreled, (2 in 6.5 Creedmoor, 1 in 6mm Creedmoor), and they’ve at least had sub-MOA grouping within the first 50 rounds. This particular rifle, however, is not good at all. Best 5 shot group is 1.27” after 50 rounds. 20 rounds of Hornady 140 grain A-Max, 30 rounds of Prime 130 grain. The Hornady had the better groups, but the Prime had the best velocity and the better SD. Just curious if I should start to worry, or give it more time. Any input is GREATLY appreciated.
Dang man. I had good groups shots 6-10. Did you figure anything out?
Screenshot_2018-02-08-22-36-50.png
 
When a rifle won't shoot at least reasonably accurately for me from the first few rounds, I generally consider load compatibility.

As a handloader, I'll usually start with the preferred bullet and do a load workup. This will identify better loads and/or possibly disclose some sort of mechanical problem with the rifle.

For shooters who are restricted to factory ammo, this potential remedy isn't available. But buying a box or two of brands/loads which sample some significant variety in loads can get you at least partway to the same outcome.

If there's no joy after this, A) it's time to talk with the Smith, and B) you will at least have some solid evidence in your corner should the negotiations go sour.

Greg