Accuracy ?

[Spino]

B1G_BORE,

Nice collectors gun there! You hit the nail on the head, I would start with free floating the barrel and bedding. This link may help you B1G BORE (feedback on your - http://groups.google.com/group/rec.guns/...636b063cbe11487

Best of luck!
Spino

[Bart B]

[ QUOTE ]
I have an old factory 670 win - 30-06 that shoots 1.5 MOA reliably when cold. Two shot limit (before letting it cool down) or it sprays. The Chrono shows consistent velocity. Any guess on the ot-six's problem?

[/ QUOTE ]There's usually one of two things that cause shots to start spraying around after the first few are fired:

* Barrel's bending from heat expansion 'cause it's not properly stress relieved. Even with the barrel totally free floated and/or the receiver epoxy bedded, it'll still happen. Happens a lot with factory barrels and many aftermarket ones.

* Shooter's changing his position and/or way he holds or shoots the rifle. Proper coaching and practice will fix this.

[edge]

It turned out the the majority of the problem was due to not using a HOT primer! Shooting in an underground range the muzzle flash was intense to say the least. The powder was not being consumed properly.

First 3 shots had a 8.9 inch spread!!

I went back to shoot over the weekend with a "known to be an OK load", and shot sub MOA. I noticed that the muzzle flash was MUCH less so I tried switching primers in the first load. Not good but under 2 MOA, which at least gives me a place to start. Swapping load weights and trying other powders should get this under moa in short order.

Thanks for the help [img]/ubbthreads/images/graemlins/smile.gif[/img]

edge.

[Bart B]

[ QUOTE ]
It turned out the the majority of the problem was due to not using a HOT primer!

[/ QUOTE ]What primer and powder type/charge in did you use that shot the huge groups?

I've used the mildest large rifle primer made (RWS 5341) in .308 Win. and three 30 caliber magnums with 10% reduced to maximum loads of several powders. No problems in temperatures from 20 to 110 above zero.

[edge]

OK, This used to be a Savage model 110 in 30-06.
I put a cheap 0.458 1:14 barrel on. The barrel fits more like a Remington as it is 1 1/4 diameter at the lug and a straight taper to 0.840 dia.

I was shooting 65 grains of N120 and a 8mm 200 grain SMK in a 43 grain sabot. I was using a Winchester LRM primer, primed in a 45 acp case. When I switched to a 209 primer things got a lot better. Not great, but better and I know that I will be sub moa shortly. I expect to go up to 70+ grains with this powder to try to find the sweet spot, but may need to switch powder if I can't get it to burn.
With a BC of .52 this will be stable past 1k and assuming the accuracy comes in it will make for some fun Summer varmint shooting.


(L-R) 45 shockwave, 200 grain SMK, SMK inside of sabot.

Did I mention that this is a muzzleloader [img]/ubbthreads/images/graemlins/wink.gif[/img]

edge.