11-16-2021, 03:26 PM
(This post was last modified: 11-17-2021, 01:32 PM by Morvandium.)
I just received my 24" Grendel barrel from x-caliber barrels. (www.x-caliber.net). Maybe this will give an additional reference point.
24" 6.5 Grendel 416R with a Rifle+2" gas system, Hbar profile with thermal fluting. Shipped weight 3.7 lbs, with matched bolt and packaging. I did not weigh the barrel alone after it arrived, but I will when I disassemble the upper for cerakoting at some point.
This is what their thermal fluting option looks like. I'm sure if you had a similar custom fluting job done elsewhere, it would result in similar weight loss to what this did.
[ATTACH=CONFIG]18388[/ATTACH]
I posted some other pictures in 6.5 Grendel Photo Gallery.
It cost a pretty penny, but I got exactly what I wanted. I wouldn't do it for every gun.
The thermal fluting is 15 straight flutes on the back end of the barrel. They are narrow, deep, close together, and done at straight 90° angles to maximize surface area and linear surface at the original diameter, and material removal. While the fluting reduces stiffness slightly because it is material removal, it drastically increases the ratio of stiffness to barrel weight, and the ratio of surface area to mass. The maximized linear surface at the original diameter preserves more stiffness than typical, decorative/cooling fluting cut at angles. It's not a miracle cure, and the tradeoff is the machining takes time using small bits, so it has a steep price tag for longer barrels.
edit: stated a ratio backwards
24" 6.5 Grendel 416R with a Rifle+2" gas system, Hbar profile with thermal fluting. Shipped weight 3.7 lbs, with matched bolt and packaging. I did not weigh the barrel alone after it arrived, but I will when I disassemble the upper for cerakoting at some point.
This is what their thermal fluting option looks like. I'm sure if you had a similar custom fluting job done elsewhere, it would result in similar weight loss to what this did.
[ATTACH=CONFIG]18388[/ATTACH]
I posted some other pictures in 6.5 Grendel Photo Gallery.
It cost a pretty penny, but I got exactly what I wanted. I wouldn't do it for every gun.
The thermal fluting is 15 straight flutes on the back end of the barrel. They are narrow, deep, close together, and done at straight 90° angles to maximize surface area and linear surface at the original diameter, and material removal. While the fluting reduces stiffness slightly because it is material removal, it drastically increases the ratio of stiffness to barrel weight, and the ratio of surface area to mass. The maximized linear surface at the original diameter preserves more stiffness than typical, decorative/cooling fluting cut at angles. It's not a miracle cure, and the tradeoff is the machining takes time using small bits, so it has a steep price tag for longer barrels.
edit: stated a ratio backwards