Tuning 300WM

N

Nukem

New member
First trip to the range today with the new .300 setup on the Mod 70.

The bedding screws are torqued at 40 inch lbs.
Loads were: virgin Rem brass, 73gr IMR4831, WLR primer, 180 gr Sierra MK

Groups were 1" at 212 yrds. Shot prone W/ bi-pod.
New barrel, I ran a wet patch and two dry ones after each three shot string.

Some 10yr old stuff I had with well fired brass ran about 1 3/4"

Same components with IMR 4350 were almost 3"
Should I try a 168gr MK with the 4350?

Should I bother playing with the torque on the bedding screws. Stock is a McMillan A4, very nice, BTW. The heavy 26" barrel and that stock tame the .300 pretty well, still wouldn't want to do 100rnds at a sitting though ;)

Any tips would be appreciated, I've been out of bolt guns for 10 yrs.
 
I would try about 79.2 with a 190nMk It should shoot if its going to The way I tune a 300 is by group spred Keep increasing the powder a tenth at a time as the vertical spread gets smaller. Ounce you reach the smallest vertical spread then the group will open up in all directions. Drop back and shoot the load that shot the smallest vertical spread I could never get enough 4831 to getthe velocity up to where it would work the best. I shot a lot of it because at 30Cents a pound you couldn't beat it the load you were shooting of 4831 was giving you about 06 velocity. That Is if my memiory serves me right
 
Nukem. If you can find some Winchester WMR powder, I can recommend two loads that do well in my Win. Mod. 70. I have a 26" sporter weight barrel. With the 180 gr. Sierra game king flat base bullet. .75 inch at almost 3100 FPS (3072 average) With the Speer 200 gr. flat base bullet, .60 inch. I have not chronographed that one yet. This was on a 95 degree day. There were no pressure signs at all.
You will have to hunt like hell to find any WMR, as the "Big W" has discontinued it. It is still around though. I found 12 pounds of it at a gun show. I bought it all.
Randy. Nukem said he was using IMR-4831. That is a faster burning powder than the Hodgden's stuff you were using. Sierra's book shows 74.6 as max for the IMR version and 78.0 with the Hodgden's. I always felt that this was a bad mistake, as someone using an older manual could think they were the same. Even some of the data in Ken Water's PET LOADS was worked up prior to DuPont, now IMR, brought 4831 back onto the market. It's real easy to look at the wrong one in newer manuals as well. If you're using IMR and happen to use the data for H-4831, you just might have a kaboom. At 73 gr. Nuken was only one grain below the published max.
Paul B.
 
You're getting 1" groups at 212 yards with a non-benchrest rifle?

That's sub-0.5 M.O.A..

Get out of the car; we've arrived. You're there, bud. What more do you want? If you're good enough, you've got a rifle that will hit the kill-zone on a deer or a man at way over 1000 yards. Not that it's sporting to do so on a deer, but you're rifle's got the capability, right now.

I'm all for tweaking, and I'm not telling you that it's worthless to continue doing so, but, for all practical purposes, I just thought I'd be the first to say: Congratulations! You're where most riflemen dream of being with their own specimens. There might be a guy out there who's got a .25 MOA sporter rifle that you've heard about... but you won't likely see him make it group like that from field positions. You, yourself, right now, have what most of us dream about.

My own Sendero in .300 Win Mag gives me just under .75 MOA, day in, day out. I'm happy with that, for an off-the-shelf rifle. That rifle is capable of making shots far longer than I'm willing to shoot, at game.

I've been using Sierra 180g GameKings and MatchKings over 70+g of RL 22 to great success, for over 3120 fps (Oehler chrono, 70 degrees, no pressure signs). The guys at Sierra suggested this load and one with RL 19 to me when I called their hotline.

Again, congrats! I'm truly envious!
 
Long Path,

It's not an off the shelf rifle, it's a custom built with premium bbl, decent optics, ect. Real heavy duty setup for some 1000yrd shooting I want to try.
I probably didn't pose my question properly.
What I want to know is how the torque on the bedding screws affect groups,,vertical strings?
Some strange observations, all the IMR 4831 would string vertically ( albiet not very much) and all the 4350 would string horizontally.
 
Nukem, Once you get this close to The Holy Grailyou need to tell all of us what you have done. If you wish to tweek the bedding torques take notes. I would not mess with the loads at all before doing the above.
Congratulations!
Hank
 
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