Does anyone have any pet loads they could recommend for my Ruger No. 1 in 7mm Rem. Mag? So far I have used 57, 58, and 59 grains of H4350 with a 140 gr Siera bullet. They group o.k. for hunting but for some reason they all shoot two shot groups of +/-3/8" with the 3rd shot being 1.5 to 2 inches out. Does anyone know why that might be, shooter error, hot barrel, wood problem?
I plan to shoot a 139 gr Hornady SST bullet for whitetails.
Thanks!!

Best advice I can give you is to buy a reloading manual and read it cover to cover. That way you can learn how to experiment safely to get a good load.

I' m guessing either the barrel is getting hot or maybe there is some fouling in the bore. Try firing one shot, letting the barrel cool 5 minutes, then firing another, repeat.

muddywater, where are you shooting? I mean what range?

I use Federal Match Grade Primers and they have really cut down on fliers. Your barrel may be gettein a little warm for an accurate third shot, or you may be a little stressed when going for that last shot. Try to relax and do every thing exactly the same way shot after shot, including case preperation. Good luck.

I am shooting at 100 yards. I wait between shots, not sure how long. A guy on another message board said he had the same problem with a 7mag and he increased his load by 1/2 grain and it fixed the problem. I' m going to retrace my steps on the reloading bench to ensure uniformity.
Thanks!!

muddywater, I meant what range as in Clark' s, Bodcau, etc.

There are hundreds of variable that affect accuracy. That' s one of the neat things about reloading. I always start out with 1/2 grain increments. Once I find one or two loads that group well, then I begin experimenting with bullet seating. The other variables have to be the same(case prep, primers, etc.). I personally love the 7mm mag. By the way, the best accuracy I was able to get with H4831 was 5/8" . RL-22 behind Sierra 140 btsp' s achieved 1/4" groups. Of course, I' m shooting a Rem 700bdl, not a Ruger #1.

Sorry for the misunderstanding. I shoot at Clark' s. I' m a member of the Caddo Rifle and Pistol Club.

I' ve got a stainless ruger 7mm mag. I gave up on the sierra' s. I couldn' t get any consistant accuracy with them. I' m currently using 68.5 grains H4130 with Nosler 140 bt' s and I' m really happy with my groups, 5 inches at 400 yards. That' s a load I worked up to in 1/2 grain increments. At 69 grains, I start running into bolt opening problems so be carefull if you try this and work up to the load that works best.

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