Point of impact shift with carbon fiber wrapped barrels

[rbuoncri]

I have a custom build in 300 PRC with a Bartlein Bull Sporter #4 CFW barrel. Have completed load development. After 6 rounds or so, POI seems to shift up and to the right (consistently). It goes from sub MOA (for 3-4 shots) to about 2 MOA. I'm waiting about 1-2 minutes between shots but the barrel still gets quite hot. Is this shift to be expected? Have I damaged the barrel? Is a POI shift to be expected with CFW barrels?

 

[Coldfinger]

I've never noticed much of a poi shift with proof, carbon six or Oregon mountain carbon fiber barrels. But they're all smaller bore cartridge's 7wsm down to 22 creed.

 

[ARlife4me]

I haven't checked any cf barrels I have yet? 30" 300wm c6, 6.5creed proof, 6.5creed bsf or 260rem proof as I haven't put any on target, only on torso sized steel.

 

[Coldfinger]

I never let them get very warm shooting either.

 

[Bob Wright]

I'd run it past the manufacturer. Also check the free float while on a rest or bipod. Hard to tell.

 

[338 dude]

I have a custom build in 300 PRC with a Bartlein Bull Sporter #4 CFW barrel. Have completed load development. After 6 rounds or so, POI seems to shift up and to the right (consistently). It goes from sub MOA (for 3-4 shots) to about 2 MOA. I'm waiting about 1-2 minutes between shots but the barrel still gets quite hot. Is this shift to be expected? Have I damaged the barrel? Is a POI shift to be expected with CFW barrels?

I've never had much of a problem with my point of impact shifting through the four proof carbon 6.5 mm barrels or my latest bartlein carbon fiber wrapped barrel.

 

[DoneNOut]

No POI shift Bart CF 308WIN. 10 shot strings and doesn't get all that hot compared to some others. Now, that was a one time test. It's designed as a hunting rig barrel so 1 shot 1 kills now.

 

[lancetkenyon]

6 rounds of 70+gr powder charge is creating a lot of heat. Slow down. Shoot 3 or 4, let fully cool.
Honestly, not sure why you need to shoot 6+ of .300PRC in a row. With a #4, I would expect it to start to walk. Could easily be mirage changing actual point of aim too.

 

[The Oregonian]

Slow down and let it cool down. Keep in mind the ambient temps play a big factor and it could be pretty warm where you are.

 

[Darryle]

I have never shot more than 2 back to back, something like I might encounter in the field. I shoot one, put the barrel cooler in and move to the adjacent bench and shoot a different rifle. The proof carbon barrels I have will create a ragged hole with 2rds consistently back to back and with 3 touching the majority of the time.

Like @lancetkenyon says, I can't imagine a scenario where you would need to fire 6+ rds with a carbon barreled rifle in the field.

 

[std7mag]

In the field, unless your on a prairie dog town, no reason to shoot 6 rounds.

But I do know of a few people that are using carbon fiber wrapped barrels as combination hunting/F-Class rifles. (20 shot strings)

If it's hunting only rifle, your better off doing a true cold bore grouping.

With a fouled bore.
Go to range & set up target at longest expected shot while your going to be hunting.

Shoot 1 shot.
Pull target & go home.
Next day repeat.
Next day repeat.

This will give you a true cold bore grouping.

 

[d11r529]

POI shift as barrel heats up is a bedding problem. Check the barrel to see if it's floated after it's heated up, should be able to slide at least one thickness of a dollar bill if not two all the way to the lug.

 

[Mark37082]

As mentioned above there seems to be something going on causing this shift. Bedding, excessive heat, or something with the barrel seems to be causing this shift. I've shot 30 rounds in a little over an hour with Sendero contour CF barrel without any material POI shift. I don't do this normally. I agree with two or three shoots and let the barrel cool to ambient temps.

 

[bultinkle]

my steel 300 pic didn't do that, nor my proof 6.5prc. Personally, I wouldn't like it