109 Berger for 600 yard benchrest???

[RichardLionHeart]

I am trying to find a stable competitive load for my 6 BRA with the 109 Bergers. I would love to hear people’s experiences. I tend to have 3 or 4 of the five-shot group nice and tight (1-1.5” at 600 yards) but almost always 1 or 2 fliers turning it into a 3-3.5” group. My barrel has shot well with other bullets. Do you think I just need to keep working at it to find a group that doesn’t produce fliers or should I just find a different bullet?

Barrel is a 4 groove 1:8 twist 29” straight contour (1.25” at the muzzle).

The 108 burgers averaged 2-2.5” five-shot groups pretty consistently evenly spread, but just couldn’t get it to go below 2”.

One guy at our club consistently posts 7-9” composites (averaging under 2” per 5-shot group).

Thoughts? I am mostly looking for those with real experience with 600 or 1000 yard benchrest and the 109 bergers.

 

[cmillard]

Honestly, with that 109 berger, I think you may need a little more twist than what an 8" can stabilize them......which could account for some fliers. My 8" twist BR, I only shoot the 105 class bullets. When this barrel shoots out, all subsequent 6mm barrels will be 7" twist.

 

[MasterYoda]

1~7.5” twist is what I would look at.

 

[MasterYoda]

800yd 5 shot 2.250” 1-7.5” kreiger 4 groove

 

[MasterYoda]

Groundhog match Berger 109’s will shoot better in a 1-7.5” then in a 1-8” from what I have seen.

 

[MasterYoda]

If your shooting a 1-8” I would stick with the 108’s

 

[RichardLionHeart]

Thanks. I’ll drop back to the 108s until such time as I can spin up a 1:7.5 or 1:7 twist barrel. I might even drop down to the 105 Bart Hammers.