I don't Know

c.read · June 10, 2012, 03:03 PM

So I went to the range today it was very windy! First things first I have a 300 win mag and I can not shoot more than 3 rounds without barrel getting super hot. So I reloaded ammo here are the results. I shot 70.6, 72.8, and 74.5. It was windy but I thought 70.6 & 72.8 shot pretty close in accuracy. I am using 200 grain sierra match king and IMR 7828 for powder and 250 cci primers. I want to shot long range. Does any reloaders have a suggestion? i'm sorry the photos turned when I uploaded them the powder weight is wrote on the paper next to them.

a7mmnut · June 10, 2012, 03:31 PM

That's a tough question--there are lots of different things to do. Are you loading to the land, and varying your OAL to check for accuracy with each load? I.E.: load two rounds at 72 grs. and to 3.330" OAL, two more at 72 grs. and 3.335", and two at 72 grs. and 3.340", then switch to the same pattern using 73 grs., then more at 74 grs., etc. Always start with a lighter load for each component. My Sierra book list the accuracy load for that heavy bullet using 64.6 grs. of IMR 4350 at 2800 fps, and the hunting load using 72.1 grs. of RL22 at 2900 fps. H1000 is also good, as is H4831. It's all about the consistency of the burn. Lotsa luck.

-7-

Jimro · June 10, 2012, 03:36 PM

The vertical stringing looks like you are getting velocity variations. Not a good sign for long range accuracy. A quick look at Hogdon's data shows 76 grains compressed under a 200gr partition, so I think you could increase the powder charge a little and see if that vertical stringing settles down.

Jimro

c.read · June 11, 2012, 09:17 PM

While I am reloading my oal varies plus or minus .002 is that going to make a big difference in my accuracy? I want to keep my shot group within a inch or two group. It comes down to I want to beable to hit a human size target 550 yards away.

Brian Pfleuger · June 12, 2012, 08:53 AM

You're still well below max charge, keep going, you may find a better load.

.002 variance in OAL is not your problem.

Your charge increases are too large too. You should be around 1% of max charge, tops. That would be .8gr at most. You are more than double that.

Check here... http://optimalchargeweight.embarqspace.com/

June 10, 2012, 03:36 PM	#3
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	The vertical stringing looks like you are getting velocity variations. Not a good sign for long range accuracy. A quick look at Hogdon's data shows 76 grains compressed under a 200gr partition, so I think you could increase the powder charge a little and see if that vertical stringing settles down. Jimro __________________ Machine guns are awesome until you have to carry one.

June 12, 2012, 08:53 AM	#5
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	You're still well below max charge, keep going, you may find a better load. .002 variance in OAL is not your problem. Your charge increases are too large too. You should be around 1% of max charge, tops. That would be .8gr at most. You are more than double that. Check here... http://optimalchargeweight.embarqspace.com/ __________________ Nobody plans to screw up their lives... ...they just don't plan not to. -Andy Stanley

June 10, 2012, 03:31 PM	#2
a7mmnut Junior member Join Date: February 27, 2009 Location: NC Foothills Posts: 1,150	That's a tough question--there are lots of different things to do. Are you loading to the land, and varying your OAL to check for accuracy with each load? I.E.: load two rounds at 72 grs. and to 3.330" OAL, two more at 72 grs. and 3.335", and two at 72 grs. and 3.340", then switch to the same pattern using 73 grs., then more at 74 grs., etc. Always start with a lighter load for each component. My Sierra book list the accuracy load for that heavy bullet using 64.6 grs. of IMR 4350 at 2800 fps, and the hunting load using 72.1 grs. of RL22 at 2900 fps. H1000 is also good, as is H4831. It's all about the consistency of the burn. Lotsa luck. -7-

June 11, 2012, 09:17 PM	#4
c.read Junior Member Join Date: June 5, 2012 Posts: 12	While I am reloading my oal varies plus or minus .002 is that going to make a big difference in my accuracy? I want to keep my shot group within a inch or two group. It comes down to I want to beable to hit a human size target 550 yards away.