When do you give up on a barrel/trouble shooting

[PathFinder]

It's in a Bravo and I swapped to a 9" TB.View attachment 760625

Keep us posted on those results.
My first 6 UM barrel was a lot like that. Shot ok at first and then never better than 1.5" by around 50 shots. A bore scope revealed that the throat was toast. Never did decide if it was the +P throat or a bunch of projectileless fire forming that killed it.

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[TaperPin]

7.5 twist.

Did you measure it?

 

[Jimbee]

Did you measure it?

No

 

[TaperPin]

No

About once a year I hear of a rifle with the wrong twist rate stamped on the barrel. I just run a sharpie down a cleaning rod, then stick it in the barrel until it starts to turn, mark it, run it in until it’s made a rotation and mark it again, and finally measure the distance traveled.

 

[Te Hopo]

I'd be trying it without the can, sometimes they can add weird harmonics IMO.

I have a CZ .17HMR barrel that was grouping horrendous with any ammo despite trying a few easy fixes like different barrel/action torque settings.
No evidence of baffle strikes in the can.

Finally I thought to remove the can and was rewarded with nice tight little groups with all sorts of ammo brands.

 

[Jimbee]

I'd be trying it without the can, sometimes they can add weird harmonics IMO.

I have a CZ .17HMR barrel that was grouping horrendous with any ammo despite trying a few easy fixes like different barrel/action torque settings.
No evidence of baffle strikes in the can.

Finally I thought to remove the can and was rewarded with nice tight little groups with all sorts of ammo brands.

I'll try a different can, but I'm not going to shoot it without, like some kind of heathen.

 

[Te Hopo]

I'll try a different can, but I'm not going to shoot it without, like some kind of heathen.

100% agreed
It took a few goes but I found another can that works on my .17HMR, I hate using unsuppressed rifles

 

[Ryan Avery]

How far are you jumping those Dtacs?

 

[Wrench]

I had a different makers tube act that way last year. I pulled it and spun on a different 2b and it is a hammer. I did everything known to man to try to get it to shoot. It scopes good and the machine work is nearly perfect....the tube just sucks.

 

[Shortschaf]

if it's in the budget, delete this thread to hide the evidence, sell the barrel for a loss, and buy a new one.

Some barrels suck. If you've tried everything, save yourself the time and start over

ETA: deleting the thread was a joke

 

[Jimbee]

How far are you jumping those Dtacs?

.05 to .06ish.

 

[ddowning]

.05 to .06ish.

It can be different for different throat geometry and reamer geometry, but I have had the best luck jumping dtacs .035-.040 consistently in several 243AI barrels from Criterion and a couple Bartlein 5R barrels. This includes 2 different reamers.

 

[ddowning]

Also, as stated above, I wound check every single part of the rifle for torque, put it in a chassis, put a known scope on it, and shoot it with a different muzzle device. If that won't group try no muzzle device. Could be the barrel is a dog, or it could be the muzzle threads. If you have a barrel vice and action wrench, make sure the barrel is torqued. The higher the torque, the better as long as you can do it without damaging anything. 100-125 ft/lbs will be sufficient, but it should be at least 100 in my opinion.

If all of that stuff checks out, talk to UM. They seem like a pretty stand up company. Even if they told me to piss off (which is not likely) I would throw the barrel in the garbage and get another one. The cost of components and your time and frustration is worth a lot more than the cost of a barrel. With a good blank, a good smith, and a good reamer, the likelihood of getting two bad barrels in a row is near zero.

 

[Jimbee]

I swapped stocks, put my 6.5 CTR SWFA 10X in the Rokstok and the 6/7 in the Bravo. I shot what might be my personal best 10shot group with the CTR. The 6/7 did it's usual thing. (The shaded group) I was aiming at the 1.5" orange dot to the left. The only thing left would be confirming twist rate and swapping scopes.

 

[The Guide]

I swapped stocks, put my 6.5 CTR SWFA 10X in the Rokstok and the 6/7 in the Bravo. I shot what might be my personal best 10shot group with the CTR. The 6/7 did it's usual thing. (The shaded group) I was aiming at the 1.5" orange dot to the left. The only thing left would be confirming twist rate and swapping scopes. View attachment 760810View attachment 760810View attachment 760811View attachment 760812

I would try it w/o any muzzle device (gasp) to verify you don't have crooked threads. Have you checked your crown?

Jay

 

[Jimbee]

I would try it w/o any muzzle device (gasp) to verify you don't have crooked threads. Have you checked your crown?

Jay

I'll add that to the list of stuff to try. Thanks

 

[TaperPin]

I know that sinking feeling when a new barrel doesn’t shoot. In my case Shilen barreled the rifle and told me to kick rocks and didn’t even want me to ship it back for them to inspect.

 

[MtnW]

Only had those types of results once . Wiser now. After playing with and trying most variables, I would say 120 rounds and then down the road it would go.

 

[huntnful]

Junk it honestly. Already WAY TOO MUCH time and effort tied up into a $900 barrel chamber job. It's super overbore and too finicky in that setup right out of the gate. Whether it's just the cartridge, or its just paired with a sub par shooting barrel. My bet is that it'll never shoot well. Also if you're worried about running a 5 shot group, straight in a row, it's also too overbore and/or the barrel is too thin for the amount of powder being burned. Nothing of optimum consistency comes from getting up and down off the gun 10 times (or even waiting a minute between shots while laying behind it) and cooling it 10 times.

 

[WKR]

Have you borescoped it? Looked at the throat? You might have a throat that was cut crooked