Range Report 2 Different groups?

[huntermanpaul]

Hey guys, just got back from the range and had a little trouble I couldn't figure out. I am shooting a Remington 700 PSS in .308 pushing a 175 grain Berger vld with 36.5 gr Varget. This is a load I have shot for three years and have consistently printed 5 shot groups at under .5moa. Well I reloaded about 300 rounds last week and took them to the range today to make sure i am ready for hunting season. I fired 10-15 fouling shots because I cleaned the rifle last night and when I went to paper i shot 6 shots consecutively from sand bags at without changing my poa. Well, it printed two separate groups about an inch and a half apart. both "clusters" measures at.381-.399. The larger cluster was about one inch above and a half inch right of the other one. I am a left handed shooter. Rings and bases are snug and I am not sure what is wrong. Any suggestions?

 

[Garvey]

1. Some barrels take more shots to foul-up and settle down, than others. That's my primary diagnosis. I HATE freshly cleaned barrels for this reason. My 260 got cleaned after 700 rounds since the last cleaning, and it took significantly more than 20 rounds for it to start behaving like it should.

2. 36.5 of Varget seems very light. When I was shooting a .308 it was with 175 SMKs then 178 A-maxes. They got 44.2 gr of Varget, and made 2700 fps on a 24" barrel. If I were you I'd see how the rifle shot from 43.5 gr. up to 45.0 gr. The majority of 308s will shoot a load right in that node.

 

[huntermanpaul]

Oops, my bad, that was a mistake. I am shooting 46.5 gr varget, not 36.5.haha. And yes, it is a compressed load. When I made the load I started at min and loaded 5 rounds working up in .5 grain increments until I started getting pressure signs and it liked 46.5 best. Thanks for the info. I will shoot it some more and see if your theory is my problem. thanks again!

 

[Garvey]

Report back, if that doesn't fix it we'll look at something else. Lowlight suggested, several times, to dry fire at least 5 times before punching paper. I have been doing this for the last year, and it's made a difference.

 

[Nate O.]

If you've got data on your initial chamber length when the rifle was shooting good, you may want to recheck that. You may need to chase the lands a bit.

 

[huntermanpaul]

If you've got data on your initial chamber length when the rifle was shooting good, you may want to recheck that. You may need to chase the lands a bit.

I didnt keep that data but that is a good point. Thanks!