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needagun
07-31-2017, 03:56 PM
Gonna build a 6.5 CM strictly for hunting. Planning on 140 gr. bullet in a 8' twist. I want to go as short as 19" if I can get good stabilization. All shots will be under200 yard. Considering ER Shaw for the $$ factor. Barrel profile will be standard hunter

SageRat Shooter
07-31-2017, 04:10 PM
I wouldn't go any shorter than a 22"... I just built a 260 rem match and went with a 25" Criterion barrel. Get's 2750 FPS with a 143 ELD-X...

Rob01
07-31-2017, 04:11 PM
Yeah a 19" should work just fine for what you want. It will stabilize the 140s with the 8 twist.

Rosco
08-01-2017, 05:47 PM
I shot 140's out of my 20 inch barrel out to a thousand yards and it worked just fine.

needagun
08-02-2017, 11:07 AM
Yeah a 19" should work just fine for what you want. It will stabilize the 140s with the 8 twist.

what about a 9 twist?

stomp442
08-02-2017, 12:27 PM
what about a 9 twist?

Would be marginal at best. You would be better off with a good 130 and with the distances you are talking about a 130 would work just fine.

Rob01
08-02-2017, 02:14 PM
Yeah it would be close especially with the lower velocity of that shorter barrel. 120-130 would be a better option.

darkker
08-02-2017, 04:20 PM
Depends upon the bullet. A Speer Hot-Cor doesn't need nearly as much RPM as a Berger VLD, remember that stability is required for a length; not a weight.
Velocity will obviously be lower, but the Creed doesn't suffer nearly as much as many cartridges when used in a shorter barreled rifle.

MV * 720 / Twist = RPM
Even if you lost 200 fps, you are only looking at a rather minor RPM Loss.

2600 * 720 / 8 = 234,000 RPM Vs. 2400 * 720 / 8 = 216,000 RPM

Rob01
08-02-2017, 04:41 PM
True but he is only shooting 200 yards so he really doesn't need any advantage a 140 would give a long range shooter. A 120/130 would do everything he needs and give him a flatter trajectory.

Iowa Fox
08-02-2017, 06:25 PM
I've watched guys shoot the CM out to 1K with a 15" barrel with success. They paid an entry fee for the match to do that, 19" will do the job.

Rob01
08-02-2017, 06:42 PM
Seen a guy shoot an 11" .308 to 1000. Hell Jerry Miculek shot a 9mm pistol to 1000. LOL

darkker
08-03-2017, 12:15 PM
True but he is only shooting 200 yards so he really doesn't need any advantage a 140 would give a long range shooter. A 120/130 would do everything he needs and give him a flatter trajectory.
I completely agree, point was only that weight isn't the thing needing stabilizing; nor that a shorter barrel would cause him a significant downfall.
The 120-130's will do anything he needs, on most any game animal able to be legally hunted.

JASmith
08-04-2017, 06:00 PM
One can go very short if weight and maneuvaribilty are important factors.

Many 6.5 Grendel shooters successfully use 16" barrels for hunting medium game at ranges well beyond 200 yards. Some rouetinely hit steel with them ar ranges beyond 1000 yards.

Velocities for the Grendel are a couple of hundred fps less than those from the Creedmoor.

Bottom line: The OP can readily go to a 19" or even a 16" barrel and have a very effective hunting rifle.