bullet too large?

I have recently aquired a custom built Ruger No. 1 with a Hart Stainless barrel, chambered for 7-08, it has a 1:9 twist.
The first 5 rounds I fired, just leaning over the hood of my pickup (after a warm up shot) made a 7/8 pattern at 100 yards with factory 140 gn. ammo.
I later loaded several different weights of bullets and powder charges to work on accuracy loads. Using a bench rest, I had marginal success. It will take me a few more trips to the range, I'm sure.

Why did the 175 gn. Spitzer BT fly all over the paper? Lucky to hit the target. Is the bullet too large for the small 308 case? or the barrel twist wrong for this load? A medium load of 40 gn. of W760 at 2400 fps.

Any one have a suggestion of what bullets would be most accurate for this gun? 130 gn. or larger 140 to 160 gn?

I can't say for sure why the 175 grain bullets are so inaccurate, but one thing to check for sure is your OAL when using them. The 175's are fairly long for that caliber so you want to be sure the bullet isn't being jammed into the grooves. If they are, you could be getting irregular pressure spikes which can cause the inaccuracy you are experiencing.

How do you know you are getting 2400 fps? Are you using a chronograph or only going on loading manual data? According to the Speer manual, 40 gr of 760 is below minimum, although Lyman suggests that it is a medium load. But neither of them say you should be getting 2400 fps with that load and that bullet.

gm41

Ruger #1's have a reputation for being inaccurate until a few things are "adjusted". The following site gives ways to accurize your #1:
http://groups.msn.com/VarmintHunting/techtips.msnw?action=get_message&mview=0&ID_Message=19295&LastModified=4675571600288923594

This is what I did to mine.

http://shootersforum.com/showthread.htm?t=17533&highlight=flashhole

The 175 gn spitzer load was carefully checked for OAL, using new unfired cases. I set them out to the limit., .05 gap. Think I'll open that up a little and use a larger charge, next time.
It looks like I'll have to throw the books away and work up to a load one shot at a time. A chronograph is still on my wish list.
Using Sierra 175 gn. spitzer,
Serra calls for 40.5 gn of 760 to get 2400 fps using Fed210 Match primer
Speer calls for 45 gn. of 760 using a CCI 250mag primer to get the same fps. That is a BIG difference in loads.

Lyman says that a max load of 43.8 gn of 760 will put out 2485 fps.
And finally
Hodgon's rifle data states that 43.0 gn of 760 is pushing a 175 gn NOS at 2495 fps.

I believe this rifle is very accurate with lighter bullets. I succeeded in getting a 3 shot bench rest group of .5 at 100 yards using the 130 gn match king sierra this morning. But I need heavier bullets for silhouette competition.

my Remington HB 700 would put hornady 139 gr bullets in one hole with any reasonable powder, i think i settled on WW748.

the one rifle i wish i had back!!!


GP100man

flashhole
This one shooter has been accurized by someone. Probably when the Hart barrel was installed. The forearm has been glassed in a rather unique way. Two 1/4" squares were hollowed out side to side in the forearm tip and bedded maybe .05 above the wood. The rear of the forearm has three small contact points glassed in, under the main spring hanger with some sort of hard plastic wedge between the hanger and the barrel. But the barrel does not float, it is tight against the wood. I'm going to leave it alone for now, until I get more shooting done. Do you think I should sand the forearm away from the barrel?

gm - I think the fewer contact points you have on the forearm the better. Hold your course for the present and see if you can find a load that shoots.

Try this too. When on the bench have the front rest as close to the action as possible leaving the front end of the forearm unsuspended. #1s can be a little finicky about how they are held. Conciously hold and shoot it the same way every time.

Thanks for the info.,

I'll post some results later, it's just too (blank) cold out there to do anything constructive right now.