August 10, 2019, 08:53 AM
x0225095Thoughts on barrel length for 6.5 Grendel AR...18” or 20”?
As the title says...
General purpose rifle for Target/Range shooting and Hunting (Whitetail & Hogs)
Can’t decide between 18” or 20”.
Leaning towards 20”...
Any forum experiences out there ?
August 10, 2019, 09:31 AM
fritzMuzzle velocity will likely be some 40 to 70 fps from the longer barrel, depending on load, for similar barrels.
The 20" barrel will weight a little more, with the additional weight depending on brand and barrel profile.
For a target shooting, where you generally don't move around much, a longer barrel improves flight ballistics.
For hunting, a lighter barrel is easier to carry.
August 10, 2019, 10:02 AM
ed308For target, 20" barrel would be my choice and what I have for my 6.5 Grendel. But for hunting, I grab one of my 6.8 SPC with a 16" or shorter barrel. When hunting, I like light weight and a short barrel. Unlike the Grendel, the 6.8 doesn't give up much when you go short on the barrel.
August 11, 2019, 06:45 AM
fritzquote:
Originally posted by ed308:
Unlike the Grendel, the 6.8 doesn't give up much when you go short on the barrel.
Fluid dynamics is behind the physics of how much a bullet gains/loses velocity as a barrel length increase/decreases. There isn't much difference in powder capacity for the two cartridges, nor is there all that much difference in bore size.
Sure, the 6.8 is a slightly larger bore, therefore its MV is slightly less affected by barrel length. But it's splitting hairs -- it's not comparable to the MV & energy differences between, say, a 223 Remy and 300 blk, for SBR and rifle-length barrels.
August 12, 2019, 01:56 PM
Phelen_KellSuppressing? Get 18. If not, then get 20.
August 12, 2019, 08:06 PM
x0225095Thanks for all the input fellas.
I got the Atheris 20”.
August 19, 2019, 09:23 PM
guardianangel762What ranges are you using it?
I have a 22" for open areas and a 12" for my brush gun.