Thread: Gun digest article on f-class rifles

The F-Class Rifle for Competition | Gun Digest

@res, check out the AR

Question from the article - One thing i generally don't understand is why fluting is bad from a heat sink point of view. When all that extra surface area is added by carving shapes into it - doesn't that dissipate the heat better?

Originally Posted by Dead is better

Question from the article - One thing i generally don't understand is why fluting is bad from a heat sink point of view. When all that extra surface area is added by carving shapes into it - doesn't that dissipate the heat better?

Yes it does dissipate it faster but due to the flutes there is less steel there so it will heat up quicker.
A fluted barrel of the same diameter nonfluted will be less rigid and will heat up quicker (not by my though in practise), but will be lighter.
So for the same weight you can get a slightly fatter barrel with flutes which will be as rigid and as good a heat sink a the thinner nonfluted.

Being a good heat sink and dissipating heat are both related but are different and one thing is usually given up for the other.
A barrel that is a good heat sink will have a lot more heat to get rid of, so once it's hot it stays hot for a long time.
A barrel that heats up quick will also cool quick.

This is from the Lilja web page .

Fluted Barrels

Fluting barrels for both competitive target and hunting rifles is quite popular. There are two advantages to using a fluted barrel. Improved accuracy is one advantage because of increased barrel stiffness. If we compare a fluted barrel to one that is not fluted, both weighing the same, the fluted barrel is stiffer. This is because the fluted barrel will be of a larger diameter than the unfluted barrel of the same weight and length. Increasing the diameter of a barrel greatly increases its rigidity. Fluting may also allow for a longer barrel, if weight is a consideration. Another advantage to fluting is the increased cooling rate of the barrel because of the greater amount of surface area exposed to the air. Please look at our FAQ section on fluting too.

Originally Posted by Dead is better

Question from the article - One thing i generally don't understand is why fluting is bad from a heat sink point of view. When all that extra surface area is added by carving shapes into it - doesn't that dissipate the heat better?

I might be completely off the mark, but here's my 2 cents

For 10-20 shot string in a relatively short timeframe,you want a barrel that is able to soak up as much heat as possible, without it starting to radiate that heat (heat SINK) - the radiated heat causes barrel mirage and affects optics.

If you have fluting it would start loosing the heat faster. You want increased heat absorption, not dissipation.

My Omark initially had the original (thinner) profile MAB barrel. 10 shot string were ok, but 15 and especially 20 shot string barrel heat became a noticeable problem.

Originally Posted by ebf

The F-Class Rifle for Competition | Gun Digest

@res, check out the AR

I shoot my 308 AR in FTR class. It goes well with 175 grain projectiles, I have shot a few 50.9's with it at 300 yards