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View Full Version : 6.8 Grendel AR upper barrel length


tpc13
02-17-2012, 4:30 PM
If I could get some info on the muzzle velocity regarding different barrel lengths. I was looking at 16" but how much will I gain if I go 18,20, or 24" barrel length. I saw some ballistics around 2510-2880 and energy to 1658-1942. Any I info would be appreciated. Oh this is going on a Spikes lower and want to shoot from 100-1000 yards.

russ69
02-17-2012, 4:48 PM
6.5 Grendel, right? The Grendel can make it to 1000 yards so you might want to not kill the velocity too much with a short barrel.

C.G.
02-17-2012, 7:22 PM
http://www.calguns.net/calgunforum/showthread.php?t=535214
There are graphs in this thread on 16" and 24". Personally, I would not go less then 20" (my Grendel is 24" without a brake).

Trickpony
02-17-2012, 8:03 PM
My Grendel started life as a 24" and I've shot the 6.5 Grendel out to 1200 yards in a similar 24" configuration and hit a 18" target 9 out of 10 times with a 123 gr. A-Max bullet. I cut my barrel down to 20" to make it more suitable for 3-Gun use and lost a couple hundred fps of bullet velocity. I was able to handload and get most of that back but I can barely make major power factor now. Anything over 20" will easily get you to 1000 yards. I wouldn't go any shorter if it were mine.

tpc13
02-17-2012, 8:38 PM
Thanks for the info. The 6.5 is looking good. Btw I spoke with sotarms today and they will custom cut a barrel length for me. Thinking either 18-20".

Trickpony
02-17-2012, 8:43 PM
Thanks for the info. The 6.5 is looking good. Btw I spoke with sotarms today and they will custom cut a barrel length for me. Thinking either 18-20".

Yeah, I have an Alexander Arms barrel that started life as a 24" and is now a 20." Alexander Arms cut it down and threaded it for me and polished it nice and bright. I also have a Satern 21" barrel that I need to build a complete rifle with sometime soon - It should be a tack driver.

gun toting monkeyboy
02-17-2012, 9:25 PM
Yeah, don't waste your time with a 6.5 Grendel in a 16" barrel. The whole point of going with the 6.5 is to milk as much long-range performance as you can from the AR platform. If you want that reach, don't hamper it by lopping 4 inches off the barrel. If you want something compact, go with the 6.8. It is designed for shorter barrels and closer ranges. Totally different philosophy for it's use. If you want the reach, go with at least an 18" barrel. 20" or 24" would be better.

-Mb

tpc13
02-18-2012, 3:31 AM
Cool tnks 18" sounds good