AR vs. Bolt gun

[RonS]

I have two 7.62x40WT's, one AR and one bolt gun. My question is would they both use the same load or should the bolt gun use a slower powder? The loads listed by Wilson Combat for the 7.62x40WT are excellent in my 18" 12T AR but when using the same loads in my 20" 12T bolt gun the groups open up. How do I determine which powder to choose when there is no data for a bolt gun? How do I find my starting point with said powder? Or do I need to shorten the length of my bolt gun? I have noticed that in the Sierra manual thier accuracy and hunting loads are different between the AR loads and bolt gun loads. Thanks in advance for all help...

 

[dcali]

The optimal loads will very likely be different. As for data, I would take a look at QuickLOAD for some guidance, and continue to ask for other shooters' input. I would definitely ask Wilson directly, since they no doubt have played around with it. As with any wildcat, be cautious.

 

[RonS]

Thanks, if someone with the Quick Load program could chime in it would be appreciated. I have a Mac PC...

 

[rmr]

this process is no different than tuning two bolt rifles for one load. chances are, a given load will shoot better in one gun -vs- the second (assuming they are identical). trying to tune a gas gun and a bolt rifle to use the same load is more difficult but the process is the same. I see no need to substitute a slower propellant for a given bullet wt, just because its a bolt gun with a longer barrel. Start with the same load for your AR and run a ladder test to find the nodes. my bet is that your AR load will shoot even better in the bolt gun, with a little tuning, all other variables equal. (same make/twist/chamber bbl, same bullet, powder.. just different seating depth/propellant charge)