6 x 45 Twist

Re: 6 x 45 Twist

I'm running a 7.7 because that's what barrel I had. The light vs. heavy bullet is the same as any other chambering. Heavier bullets tend to have a better BC than light bullets (not always). Heavy bullets don't go as fast so you need to find the balance.

With the 6x45 in a bolt gun the Berger 105s look to be that balance.
 
Re: 6 x 45 Twist

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nashlaw</div><div class="ubbcode-body">What twist are you running and what bullet weights? What are the advantages and disadvantages of the heavier bullets in this chambering? </div></div>

The answer depends on the magazine length available. If you have to run in a 2.3" (AR15 mag) length, then about 95grs is your limit. If you can run a longer AICS mag length (2.5") then you can run up to 107's. Depending on your barrel length, 105-107's run about 2600-2700fps, which ballistically matches a .308Win shooting 175's quite closely. An 8-twist is the most flexible.
 
Re: 6 x 45 Twist

I have a 9 twist on mine. I have a number of other 6mm rifles that are better suited, IMHO, at slinging heavier bullets. I built my rifle as a hunting rifle, primarily to shoot 85-87 grain bullets. Steve Thimm, who worked for kimber of Oregon back when they were making 6x45s as factory rifles stated that in all the testing they did, the 9 twist was the most consistently accurate, so that was a contributor to my decision.
 
Re: 6 x 45 Twist

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 264Charlie</div><div class="ubbcode-body">I'm running a 7.7 because that's what barrel I had. The light vs. heavy bullet is the same as any other chambering. Heavier bullets tend to have a better BC than light bullets (not always). Heavy bullets don't go as fast so you need to find the balance.

With the 6x45 in a bolt gun the Berger 105s look to be that balance. </div></div>

What kind of velocities can a 223-size case push 105s?

I did a lot of research on the 6x45 a few months ago and saw I might be able to get 2700-2750 with a 95gr SMK/VLD from a bolt gun.