Point of impact shift with carbon fiber wrapped barrels

[kgunz11]

I have never seen a chamber increase much in temperature, it only receives radiant heat. I think you were given poor info there.

Maybe he wasn't the most articulate in his wording, but the point he is trying to make is 100% accurate.

 

[rbuoncri]

Take any #3 contour barrel and shoot 6 rounds of 300 PRC and I promise you the groups will start to walk from heat. There's nothing wrong with the barrel, the carbon wrap, the rifle, or the ammo. It's just how the steel responds to getting that hot. They claim CF dissipates heat faster, but independent testing has proven that Carbon Fiber wrapped barrels hold heat longer than a steel barrel of the same size.

I like carbon wrapped barrels for what they are. I build guns with a bunch of them, and I know their limitations.

Thanks. That sounds like the most reasonable, common sense, explanation. I still am awaiting a response from Bartlein.

 

[Dirtrax]

Maybe he wasn't the most articulate in his wording, but the point he is trying to make is 100% accurate.

The chamber is indelibly connected to the rest of the barrel. It's more than radiant heat, it's physically transferred heat as well. High rates of fire over time will unquestionably make a chamber hot. I'll agree it's not likely as much of a factor in your average slow fire range session.

 

[VarmintBob]

Like anything else, you won't fine that ALL or even MOST carbon fiber wrapped barrels do the same thing when the barrel heats up.

 

[Longtine88]

Well I shoot lots of CF barrels. Build all of them now myself. I don't have that issue to that extreme. I can run 10 shot strings on a .2 moa shooter with 3-5 shot groups and only opens up maybe to .6 moa or so with 10 string shots or so. And some of that could be me. And that's from 20" to 28" barrels, 22 cal to 338 cal. Maybe I'm just lucky. I will add, I've never experienced anything like that with a Bartlein barrel. As mentioned.... you may be having heat transfer type equipment issues. Could be a lot of things. Tough going through the discovery of the problem. I fixed a friends rifle that did a similar string issue. After looking at it what I found was several things, a gap between the back side of recoil lug and the bedding, bedding was touching left side of recoil lug, action face was not square with the shoulder, and one bolt lug was barely making contact on the back right side. So I fixed all his issues and now the problem is gone. I guess I have a different view of it cause we deal with heat in Texas daily lol. It's 108 right now and I'm fixing to go shoot a rifle that uses a certain powder I like and I want to see the diffence in 50 degree work up and 108 in this particular combo. Good luck finding it.

 

[Longtine88]

And to add.....I just got done shooting a rifle that I loaded for back in late winter. I developed it at 50 degrees and shot down to 28 degrees. But nothing hot. It's a rifle that I build my daughter. Anyways some guys were wanting to know real life velocity increase on hot days, well it's 109 and I'm soaked and just gone done shooting a 12 shot string. Now keep in mind the heat waves were horrible. I mean I was using edge of target to edge of target with cross hairs in the middle type bad. 12 shots in 1.6" at 300 yards. And it's 59 degrees hotter than the days I've shot the loads on.

 

[Barehandlineman11]

Heres 10 out of norma improved i just finished 5 at 92.5gr h50 and 5 93 grains this was back to back at 84 degrees. 28" proofs do walk. First 5 were a .3-.4 group. Same gun shot 4 inch 4 shot group at 1300 and 8 1/4 inch 3 shot group at 2100 letting barrel cool between shots