300 Norma Mag build, finally shooting

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Seems that N570 is the magic dust for this cartridge but that Retumbo load shoots very well. Yours is the first Remage MN I have seen, nice rig !
 
If it closes hard you'll want to set the die a little deeper to bump the shoulder back a couple more thou. It's the reason bigger magnum cartridges cant neck size only. As stated before if it closes hard it will open hard. My Smith makes me guages with my reamer out of scraps of barrel that I use for headspace guage. .002/.004 works well.
Also try rl33 or imr8133 as good powders for NM heavies. N570 is a unicorn powder. N565 is easier to get and will probably work well also.
Retumbo might be a touch fast leaving some speed on the table.
 
If it closes hard you'll want to set the die a little deeper to bump the shoulder back a couple more thou. It's the reason bigger magnum cartridges cant neck size only. As stated before if it closes hard it will open hard. My Smith makes me guages with my reamer out of scraps of barrel that I use for headspace guage. .002/.004 works well.
Also try rl33 or imr8133 as good powders for NM heavies. N570 is a unicorn powder. N565 is easier to get and will probably work well also.
Retumbo might be a touch fast leaving some speed on the table.

Yeah I ended up turning that die down a bit more, really had to contact the shell holder pretty hard to bump my shoulder down enough for easy bolt closure.

I've got some N570 coming so I'll give it a try here soon with 230's.
In the meantime I HBN coated my bullets and found an awesome load with 215's and H1000.
I'm getting consistent 1/2" groups at 200 yards running 3050 fps, I might try some more 225's HBN coated.

The 300 NM is really starting to impress me, I went out last weekend and center punched a 12" plate at 820 yards with a 10 mph crosswind on the cold bore shot.
Ended up with 3 out of 5 hits in gusty wind.
 
Good luck. Thinking about going with 30-28 nosler. Those are pushing the 215 around 3080 fps with retumbo.
 
Good luck. Thinking about going with 30-28 nosler. Those are pushing the 215 around 3080 fps with retumbo.
I hear ADG 30 Nos brass has a capacity of 101 grains, only 2 off the NM.
Might be worth going that route
 
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