Carbon barrels

[Foxyboy43]

Is it true they only make them for the 6.5 Creedmore?
Tusker

 

[Emilio]

That example isn't really the comparison that I'm making though. The rate of heat transfer from welding into the steel is significantly greater than the rate of heat transfer from the steel into the surrounding air as it cools down. So no, the time it takes to cool down will be much longer.

To make a fair comparison example, run a 6" weld at 180 amps on 5mm plate (lightweight barrel) and 15mm plate (heavy weight barrel). 180A on both because the heat energy input has to be equal (same number of shots).

The 5mm plate will be hotter than the 15mm plate, but it has a smaller thermal mass so will initially cool at a faster rate than the 15mm plate. There is a crossing point where the 5mm plate will become cooler than the 15mm plate, even though the 15mm plate starts at a lower temperature. Both will reach ambient temperature at roughly the same point.

What that means, is that unless you are doing very long shot strings, a heavy barrel will heat up less and therefore have a lower risk of POI shift.

Multi material barrels like carbon wrapped ones require a bit more thinking

Thin barrels are always a trade off but often very acceptable in normal shooting scenarios.

With a mix of materials it can be a bit different, apparantly some manufacturers are adding aluminium particals to the resin to get better heat transfer from the carbon.
If my R8 keeps shifting POI like it now seems to do after the first shot/shots with all ammo, I will give carbon a try to see if that is better.

 

[oldhamstocks]

I have a Bergara Cima CF with a carbon wrapped barrel (20 inch 1:9) in .223. Put 40 rounds through it on the range the other week to verify a BDC reticle at the distances out to 500 metres and it performed brilliantly, no heat related issues impacting accuracy.

Looks cool AF as well