I'm shooting a Sako L691 in a .300 Magnum wildcat based on the .300 Weatherby case. The barrel is a 1-12" twist Pac-Nor, 26" with a .750" muzzle, standard Weatherby freebore. The gun weighs about 10.5 pounds. Scope is Leupold 3.5-10. I shoot the 200 Nosler Partition using 81 gr. of IMR 7828 for an average muzzle velocity of 3058 fps.
I can only get 5 shot groups down to 1.25-1.5" Is there anything that will improve the groups?

I would try the accubond in 200g, and also in 180g. I would think that 1 in 12 may be a bit slow for the 200g to be really happy. My freind's Sako 300 RUM shines when up near max with the heavy bullets (mine is still in the workup process, but seems to show the same traits).....from its 1 in 11 twist barrel.

Also, try shooting at 200 yards in case the bullets want a bit more time to settle down.

I would also try the TSX bullets. They seem to be forgiving of freebore and work wonders in many fussy rifles.

As you know, that group will probably be more than adequate to kill the size critters it's meant for--but it would annoy me as well.

If you don't do a lot of bench shooting you might see if you can find someone who does to give it a go. I am typically the weakest link in the chain myself.

Is that one of the standard, or one of pac-nor's polygon barrels? I've been interested in poly barrels and not found too many folks to talk to that have them.

Good luck,

Dan

My guess is that it's the standard, not polygon. The rifle was built several years ago.

I was concerned about the twist being a bit slow. Maybe 180s are the right way to go. But the velocity is so good, I don't want to give up on it.

I routinly shoot 1.5" groups at 200 yards and hold moa out to 400 with my Mark V Alaskan using 200 gr. Partions. Though this is with a 1-10" twist rifle. But, I think that 1-12" while not optimum for 200 grain bullets, should be fine.

I used to burn 7828 by the barrel but switched to H1000 and haven't looked back. It gives me much better accuracy at longer ranges with simialr velocities. I also use CCI 250 primers.

Being a custom affair I'd assume the rifle is mechanically sound, but it never hurts to check the bedding and action screws etc...

Check out the comments about the 200 gr. Partition in this thread over at the 24HourCampfire. It should leave no doubt about the accuracy potential of the bullet itself.

Partition Thread

I should have asked, what kind of velocity are you getting?

Though I don't shoot one of the ones you mentioned, I do shoot a 338-378 and it too is a 1 in 10 twist... Even my '06 is a 1 in 10 twist... I understand you like the velocity but it sounds as though that one was designed for long range shooting using 165/168 or 180 grain bullets...

Ken....

Using 7828 I could get 3100+ fps with no pressure signs. But for all I know that could have been at 90 Kpsi. That also was with a specific lot of brass that weighed about 15 grains less than any .300 Wby. brass I've ever worked with. I backed off to 3050 fps.

With H1000 I've gotten close to 3100 fps but my current all time favorite load is at a running average of about 3040 fps.

I've spoke with several long range bench rest guys and they've told me to try for 2975 to 3025 with the 200 grain .308 bullets. That seems to be the consensus with them for precision at longer ranges.

I'm not a benchrest shooter but a hunter and I load my 300 RUM with 96 gr. of Reloader 25 Fed 215M primers and Berger 185 VLD bullets. The 185 Berger is for 1-12 twist barrels which mine is. Pretty hot load, 3382 fps is my average velocity out of my 27.5" barrel. .75 inch groups at 300 yd and 2.75 inch at 500 yds. The 185's make a big ol hole in a deer. Id definitely start with a lighter powder charge and work up. Good Luck and God Bless, Louis

Slancey,

Out of curiosity, what is your wildcat version of the .300 Weatherby?

It's called .30 Tejas.
It's something like an ICL Super Magnum, or one of the group of older long .300 Magnums found in P. O. Ackley's book on cartridge reloading.
The gunsmith claims he invented the round. I think he maybe altered an existing chambering by a little and gave it a new name. He also claims it will get 4000 fps with 125 grain bullets. Not sure whether to believe either claim.

Sorry, it's like the .300 Ackley Improved Magnum, the .300 Mashburn Super Magnum, and the .300 ICL Grizzly, according to P.O. Ackley. The case has straight walls, very sharp shoulder angle, and short neck. Too bad about the long throat.