03-20-2020, 01:17 AM
Michigan,
In an AR I don't think you need to go thicker than .75" at the gas block. Like the other guys are saying, a Lilja 740 or 319 profile (I prefer the 319) is more than enough to be a tack driver if using a top-tier barrel like a Bartlein.
I would have a look at the machine drawings on Lilja's website for examples of 18-20" profiles that are excellent length, diameter and weight compromises.
Fluting will not make a barrel of the same diameter stiffer, it makes it lighter with more surface area for cooling. It can also introduce stress in the barrel and that will influence POI as it heats up.
The weight saving of fluting will not blow your socks off when you look at the numbers. Lilja's fluting of the 740 profile shaves a whopping 0.2lbs off a 2.4lb barrel. In his 319 profile fluting shaves 0.3lbs off a 2.47lb barrel. If I had my time again I would not spend an extra $100 or 20% to save a measly 0.3lbs.
Spiral or straight fluting...I don't know. Apart from camouflage I don't care what it looks like.
Good luck with your Bartlein.
In an AR I don't think you need to go thicker than .75" at the gas block. Like the other guys are saying, a Lilja 740 or 319 profile (I prefer the 319) is more than enough to be a tack driver if using a top-tier barrel like a Bartlein.
I would have a look at the machine drawings on Lilja's website for examples of 18-20" profiles that are excellent length, diameter and weight compromises.
Fluting will not make a barrel of the same diameter stiffer, it makes it lighter with more surface area for cooling. It can also introduce stress in the barrel and that will influence POI as it heats up.
The weight saving of fluting will not blow your socks off when you look at the numbers. Lilja's fluting of the 740 profile shaves a whopping 0.2lbs off a 2.4lb barrel. In his 319 profile fluting shaves 0.3lbs off a 2.47lb barrel. If I had my time again I would not spend an extra $100 or 20% to save a measly 0.3lbs.
Spiral or straight fluting...I don't know. Apart from camouflage I don't care what it looks like.
Good luck with your Bartlein.