Thompson/Center Venture issue?

[D Richardson]

My friend bought a Thompson/Center Venture in .270. We went shooting this morning and had some interesting results. We verified the 100yrd 1 moa accuracy guarantee with cheap remington 150gr. core-lock ammo, which really surprised me considering this is far from match grade ammo. It got really puzzling when we went out a little further, at 300 yards he couldn't hit anything (wasn't even able to keep it on a 24 inch square target reliably) . I checked over the gun and nothing was loose and then reverified the 100 yard zero and it was OK. I notice that this ammo is at the high end of .270 ammo as far as weight goes and the twist rate seems slow ( 1:12).

Is 1:12 twist too slow for that weight of a bullet in a .270?
any one have any better ideas as what to check or try?

Neither of us are pro shooters by any means but we both can shoot pretty well, so it isn't necessarily the gun or ammo, but we both had easy MOA groups throughout the morning. next time we go we're going to take some lighter and higher quality rounds to see but I just wanted to see what yall say.

Thanks for any help,
Daniel

 

[42769vette]

Re: Thompson/Center Venture issue?

how did you get dope for the 300 yd shot? where you gettig hits all over the 24 inch square or were they all in the botto, left, right areas of the target?

 

[D Richardson]

Re: Thompson/Center Venture issue?

there was no group really, mostly seemed to be all over the place. we were just thinking maybe the slow twist and heavy bullet weren't stabilizing the bullets past ~100yrds. we didn't notice any key-holing though. We just used my dope for my .308 as a rough estimate since we neither had any experience with .270's

 

[Shortdraw]

Re: Thompson/Center Venture issue?

Have either of you shot 300 yards regularly? I have watched a few friends get pretty poor results at 300 and they shoot fairly well at 100. Had them shoot my rifle that averages 2" @300, and poor groups.

 

[D Richardson]

Re: Thompson/Center Venture issue?

yeah neither of us are what I would call excellent shots but I was shooting ~4.5 inch groups at 300 this morning with my FN PBR in .308. I know thats not great but I'm still pretty new and still learning. I may be completely wrong and not at all trying to sound cocky but I don't feel it was the shooters. We'll find out in a week or 2 when we get back out to shoot.