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View Full Version : model 14 flat back 243 Win - any idea on barrel twist rate ?



Westcliffe01
11-17-2014, 10:05 PM
I just got an earlier (pre accutrigger) model 14 in 243 Win, serial # G192474

Before I go out and buy bullets to work up a load for it, I would like to know what the barrel twist rate is. I know all of the new stuff is 1:9.25 but does that apply to the pre-accutrigger models ? I would like to use the heaviest/highest BC load I can and I know with the 1:9.25 that was the 95gr SST. None of the longer / pointier bullets like the 95gr Berger would group. If it is a 1:10 then I might have to back down to something in the 75-80 gr range.

This is intended to be a coyote engagement rifle for a woman and the goal is to keep it light, recoil moderate while keeping the ballistics as good as possible for 250+ yards shots.

darkker
11-18-2014, 11:42 AM
Pretty sure they are a 10-twist, but get your cleaning rod out and measure for yourself.
The SST's will happily stabilize with a standard 10-twist, as will 99% of the 100gr. Just stay away from the VERY long match bullets.

http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

Look up the lengths from this link, then fill out the details and it will let you know if there is any hope of stabilizing.

Westcliffe01
11-18-2014, 12:22 PM
I bought some 87gr Vmax bullets last night. Have never previously been able to find that weight, but had heard about them. Unlike the 223 Vmax bullets I was familiar with, these have a "real" boat tail and the BC is reportedly pretty good (0.40). I will have a first go with these and move on if needed. The Vmax will have the right fragmentation characteristics on smaller critters like coyotes. Nice extra is a very reasonable price...

darkker
11-18-2014, 07:58 PM
I love the 58gr class bullets from my 243 for coyotes, They really aren't difficult to kill.

Westcliffe01
11-18-2014, 08:53 PM
When the wind is blowing, the light bullets get blown way off track. 55gr Vmax out a 223 were being blown 3 feet at 300 yards. 75gr HPBT in 223 only 8 inches. But the drop on the 75gr is significant and you have to be dead on with your range or you miss in elevation. The 243 with 95gr Bergers is better on wind and elevation compared to the 223 75gr match ammo.

I seldom get a shot under 250 yards and the wind is blowing more often than not, especially in winter.