1:8 Twist Rate Requirement on 7mm 162 A-Max?

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Rmeju

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I picked this bullet for long range shooting, because I really like the BC. I've been working up a load for it, and have been getting great groups (for me... pics here), at least at a hundred yards. I just noticed that the box says the bullet needs a 1:8 twist, but my rifle is 1:9.25.

Obviously, if I'm happy with my actual targets, then I'm happy. My question is, will this hurt me at ranges past 100 yards? Or if they shoot well at 100, will they shoot well at 1000?

Rifle is a Rem Sendero II SF (26" barrel), if that matters.
 
If it groups well in your rifle I would continue to test it, but I do think it is possible for an understabilized bullet to shoot well at 100 but become unpredictable somewhere along the way to 1000. There's a lot of real estate between those distances. But based on your initial groups I would certainly not simply abandon the load due to a theoretically incorrect twist rate. Individual barrels prove those formulas wrong on a regular basis and your rifle and load may stabilize it just fine. I would at least try some groups at 200 or 300 yds first; if those show the same promise and your load stays supersonic to 1000 I bet it carries through okay.
 
From my calculations that bullet is stable at 2600fps at 1:9.5" so I think your good.

Give JBM a look, the info on the boxes are pretty generic because the manufacturer dont know what chambering the bullet will be used in.
 
I've fired 180gr Berger VLD's in a stock Rem 1:9.25 barrel and they were stable all the way to 1000. I would not worry about it (I am at high altitude though).
162gr does not seem that heavy for that twist.
 
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