What is the best bullet weight for .260 with 1/9 twist. I am getting ready to buy some bullets for reloading. I am looking at 120 and 140. I just dont know which will stabilize better. Thanks
- Thread starter keith jones
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Re: 1/9 twist .260?
I use this alot. Hope this helps.
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
Most of the bullets lengths you need are here:
http://www.jbmballistics.com/ballistics/lengths/lengths.shtml
I use this alot. Hope this helps.
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
Most of the bullets lengths you need are here:
http://www.jbmballistics.com/ballistics/lengths/lengths.shtml
Re: 1/9 twist .260?
I don't foresee much trouble with either, but the 120 should definitely stabilize in a 9 twist better than the 140. Best way to find out is to load some and check for keyholing. It's really a case by case basis; I've seen 9s that shoot 140s and 142s all day long and other 9s that make em quack like a duck.
What kinda shooting are you gonna be doing? You should look into the 123SMKs
I don't foresee much trouble with either, but the 120 should definitely stabilize in a 9 twist better than the 140. Best way to find out is to load some and check for keyholing. It's really a case by case basis; I've seen 9s that shoot 140s and 142s all day long and other 9s that make em quack like a duck.
What kinda shooting are you gonna be doing? You should look into the 123SMKs
Re: 1/9 twist .260?
I think it's hard to say. Barrel length and velocity have a lot of bearing on this question right around the critical point in the rpm curve.
I'd say that with a longer barrel and a higher velocity, more RPM should be generated. But some folks don't agree with that, and honestly, I really don't know which side of this debate is right.
I'd be very comfortable with 120's and maybe not quite so confident about 140's. I have actually had something that looked a lot like keyholing occur with 120's and a 1:8" twist at 1000yd. You'd have to try them to be sure. It's actually something (a 1:9" twist barrel) I'm sorely tempted to try. If it works at all, I believe it'll actually work very well.
Greg
I think it's hard to say. Barrel length and velocity have a lot of bearing on this question right around the critical point in the rpm curve.
I'd say that with a longer barrel and a higher velocity, more RPM should be generated. But some folks don't agree with that, and honestly, I really don't know which side of this debate is right.
I'd be very comfortable with 120's and maybe not quite so confident about 140's. I have actually had something that looked a lot like keyholing occur with 120's and a 1:8" twist at 1000yd. You'd have to try them to be sure. It's actually something (a 1:9" twist barrel) I'm sorely tempted to try. If it works at all, I believe it'll actually work very well.
Greg
Re: 1/9 twist .260?
123 or 130s.
123 or 130s.
Re: 1/9 twist .260?
PGS is shooting 130 Berger's at 3k in a 24" 9 twist barrel.
PGS is shooting 130 Berger's at 3k in a 24" 9 twist barrel.
Re: 1/9 twist .260?
The 120s will stabilize. It's so close on the 140s that it might come down to what 140s you are looking at. The longer they are the harder they will be to stabilize. The 140gr SMK is only 1.31" long and should stabilize just fine. The 140gr Berger Hybrid is 1.426" and may not stabilize. Which 140gr are you looking at? I think it would suck not to be able to use 140gr since being able to push that bullet fast enough seems to be the main advantage of a 260 over a 6.5x47.
The 120s will stabilize. It's so close on the 140s that it might come down to what 140s you are looking at. The longer they are the harder they will be to stabilize. The 140gr SMK is only 1.31" long and should stabilize just fine. The 140gr Berger Hybrid is 1.426" and may not stabilize. Which 140gr are you looking at? I think it would suck not to be able to use 140gr since being able to push that bullet fast enough seems to be the main advantage of a 260 over a 6.5x47.
