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Joined: Jun 2019
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Thanks for your help in advance. Short version - 1:9 or 1:8 for the Newton (~6.5-06) with 125-140 grain bullets?
Long Version - I have a .256 Newton in the baby steps phase. I have brass and dies, and plenty of bullets already as I have other 6.5s, and a couple potential donor actions (1909 Arg Mauser and '03 Springfield) I'm not hung up on a Gucci custom barrel but a good one from Douglas, Shilen, et.al would suit me just fine. There's a sale at Brownells right now I might play in but while I lean towards a 1:8 twist, most of the off the shelf contoured (thinking #3 or maybe #2) .264 blanks are 1:9, which I think is the historically "normal" .264 twist until everyone went Creedmoor crazy with the high BC bullets. The 256 Newton is capable of a comfortable 2900 FPS with 140 grain and 3000+ with 130 grain bullets. I typically hunt between 3,000 and 7,500 MSL. I expect to shoot mostly Noslers (AB and Partition) in that weight class but might try some of the sleeker 140s. At the velocities the Newton gives (very much like the 6.5-06) is 1:9 plenty, or would I be advised to get a 1:8, even if I have to special order it or pay a little more? I plan on CM steel vs. stainless, as this will be a "classic" blue and walnut rifle (though I have heard there's a Cerakote color that's a dead ringer for rust blue - might consider that and go SS if I do - suggestions there are much appreciated too.
Thanks to all, Rex
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Joined: Feb 2005
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I would go 1 in 8. Nothing to gain with a slower twist in my opinion. My 256 Newton is built on a first model newton action that somebody had rebarreled to 30-06 and I had the same question when I rebarreled it back to 256. I went with a 1 in 8 twist and would do that same thing again. Bullets aren't getting any shorter.
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Joined: Jun 2019
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Thanks!
EDIT: Who did your barrel? I'm looking for a good smith who has a .256 Newton Reamer. Or these days, does everyone just rent the reamer when they get an order for an oddball like that?
Cheers, Rex
Last edited by TRexF16; 02/11/20.
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Joined: Apr 2011
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Campfire Ranger
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Campfire Ranger
Joined: Apr 2011
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Same here, 1-8 will cover you for about everything, no reason to have not have the best since you’re paying good money and you never know what bullet you just might wanna try in the future.
Semper Fi
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1:9 is plenty fast for those bullets. Even if you want to shoot 160s the 1:9 should stabilize them and you won't have problems on the lighter end.
What goes up must come down, what goes around comes around, there's no free lunch. Trump's comin' back, get over it!
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The gunsmith who did my barrel has since retired, but he did rent the reamer. For what it’s worth, I’ve shot 160s all the way down to 120s with no problems.
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Campfire Kahuna
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Campfire Kahuna
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TRexF16,
Actually, the historically normal twist-rate for 6.5's was around 1-8, to stabilize round-nose 160's at around 2200 fps--which was about the muzzle velocity of the four early 6.5 military rounds, the 6.5x55, 6.5x54 Mannlicher-Schoenauer, 6.5 Arisaka and 6.5 Carcano. The exact twist varied a little, partly due to the rifling method used in those days, but was never as "slow" as 1-9.
The 1-9 twist only became "standard" when American companies started making 6.5-caliber rifles, which began with the .264 Winchester Magnum in the late 1950's. Back then most American riflemakers were paranoid about "over-stabilizing" bullets, which was somewhat of a danger, due to most bullets being poorly-balanced in those days. Which is why the .260 Remington got saddled with a 1-9 twist in the late 1990s, one reason leading to its low sales: At just about the same time, higher-BC (longer) bullets started becoming more popular, due to laser rangefinders, which did not help the .260 in a couple of ways.
Today there is absolutely no disadvantage to a 1-8 twist, due to such well-balanced bullets. In fact it was one of the big reasons the 6.5x55 became a popular target round with 140-grain boattail spitzers, even in the "thick" cool, lower-elevation air of Scandinavia around 80 years ago. The "listed" twist of 6.5x55 military rifles was 1-8.66, but I have measured several and they've all been closer to 1-8.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
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Thank you John, I really appreciate you taking the time to explain all that to me. 1:8 it shall be. Cheers, Rex
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Campfire Tracker
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Campfire Tracker
Joined: Mar 2003
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Back when I built my 6.4-'06 c.1982 the available barrels were 1 turn in 9" twist, so that is the twist of the Shilen barrel I used. I have shot different bullets in it besides the 140 gr Spire Points I normally used for hunting, but only the Barnes Original 165 gr Semi-Spitzer showed stability problems with groups opening to 4+".
The data I have from that period showed a 7.87" or 200 mm twist as common for 6.5mm rifles in Europe.
jim
LCDR Jim Dodd, USN (Ret.) "If you're too busy to hunt, you're too busy."
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