7mag loads

[fisrtcoueswas80inches]

picked up a 7 mag the other day. have dies on the way and 3 powders to choose from. R22, h4831sc and h4350. i have read and heard a lot of good things about the reloader line but this is my first experience withthem. the bullet will be 120 gr TSX. what i am wondeing is who has had the best succes with those 3 powders?
Casey
also, where should i start on powder charges?

 

[Piker]

There was a time 10 to 15 years ago, when my best 7 mag load was 72 grains of RL 22 behind a 120 grain Barnes X. This was before I learned that the X bullets should be seated well off the lands. I was loading just touching the lands. In retrospect, I now suspect that when this load stopped shooting tight groups, it may have been because lands were advancing, and I wasn't chasing them with my seating depths.

My gun now likes RL 19 behind the 140 grain XLC seated .050 off the lands. I've thought about trying the 120 TSX, and if I do I'll definitely work up a max load with RL 22 to see how it works.

I never tried H4831sc or the H4350, but I did burn a lot of IMR 4350 without any consistent success. I have a can of H4831sc that I'm trying in my 6mm AI, so I'd be intrested if you have any luck with that powder.

 

[Djones]

I have used H4831 exclusively in my 7mm Rem Mag. My favorite bullet is the 154gr Hornady Spire Pt.
As I understand it, this bullet is now available in a BT version.
My two back ups are the Speer 145gr SPBT and the Sierra 160gr SPBT.
All have served me well.
I am not sure what the policy is regarding disclosing exact powder charges so I will refrain from doing that.
I use Winchester Brass and CCI250 primers.
Do not hessitate to use the R22, you may find that going to a even slower burning powder might be useful. Be sure and use a cronograph as you develope your loads.
The 4350 is to fast burning for my tastes in this cartridge.

Don

 

[fisrtcoueswas80inches]

that is something i dont understand, slower and faster burning have never understood that.


h4831sc has performed awesome in my 270wsm and 7RUM. buth guns shoot under 1/2 with 140 accubonds. the wsm produces 3300 fps and i think the 7rum does about 3500+ but not 100% sure.
Casey

ps, this 7mag is going to be used to longer shots so i want it to be a flatt shootin accurate mother!

 

[RELH]

Casey;
If you have other rifles that shoot great with H4831, I would try that powder first on your new rifle. If you get the accuracy and velocity you want with it, it makes it more simple to have just one powder that does it for 3-4 rifles then having a different powder for each rifle. If the H4831 does not give you the results you want, then try one of the others until you find your load. I use mostly IMR4350, but my Father-in-law used H4831 for his 300 & 7mm weatherbys and both rifles would average 3/4 inch groups at the top load for velocity. He took 4 rams and 1 billy goat with those rifles, and the closest shot was 400 yards. He put two shots, 3 inches apart, in his billy goat and the range was just over 600 yards.
Have fun at the range.
RELH

 

[OSOK]

http://recipes.alliantpowder.com/rg...p=3&cartridgeID=1068&bulletID=241&powderID=14

I worked up 4 different 5 shot groups at .5 grain intervals and 70.0 ended up being the one I went with. The rifle shot 69, 69.5 and 70 grains groups inside of the same 1" square. Basicly a pick and choose so I went with the hottest. Since then the rifle has produced multiple sub .5" 5 shot groups shooting prone from a bipod. I'm using the 140 grain Accubonds though. The 600 yard capabilities of this round are amazing.