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Old 01-17-2019, 02:06 PM
Talyn1 Talyn1 is offline
Join Date: Mar 2015
Location: Montana
Posts: 188

If someone wants to use bullet weights above 77 grs go for a 1:7 twist. Otherwise a 1:8 is fine and no manufacturer would be making barrels with that twist rate if it wasn't.
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Old 01-17-2019, 02:35 PM
Rootsy Rootsy is offline
Join Date: Feb 2013
Location: Monroe, Michigan
Posts: 1,903

1:8 will generally be adequate to stabilize 80s. 1:7 provides a margin of safety though. I have had a few 8 twist barrels on my rifles and all shot 80 SMK / Nosler fine. I use nothing slower than 7 anymore just because I never want to worry about it and I never know what I may get a mind to try to do.
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Old 01-17-2019, 04:22 PM
WindLogik WindLogik is offline
Join Date: Dec 2012
Location: Washington State
Posts: 2,353

I use 7 and 7.5 barrels. I've used 69 to 80s in them and not had a problem.
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Old 02-13-2019, 09:39 AM
rich56 rich56 is offline
Join Date: Dec 2009
Location: Jersey Shore, Vero Beach Fl
Posts: 40
Default White Oak 1-7”

I just bought the same upper. I struggled with 1/7-1/8”. I decided 1/7” wouldn’t hurt with the 62gn bullets I would be using for short course and give me insurance for the 75-80s I’d also be using. I just sighted and broke in the rifle shooting off the bench. Most bullets in the X ring and all in the 10 on a SR-1c target using Winchester W3261 62gn open tip. Some other groups 3/4moa. So far the combo is working.
PS Burris Mtac is fine too. Clear, lit retical circles the bull perfect for me.
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Old 02-13-2019, 02:27 PM
Kilo-Sierra Kilo-Sierra is offline
Join Date: Feb 2010
Location: Atlanta
Posts: 566

I have had 1-7's and 1-8's. I have shot 52's through 80.5's with each twist and did fine. Last 4 barrels I have bought have been 1-7's. I just don't see a downside of a 1-7". Chances are both would serve you well.

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