7mm Rem Mag

[Adam Van Camp]

Please remember this is from memory. I have everything writen down at the house. If I remember correctly. I am seating to 3.265. That is 0.025" from the lands.

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[tabascoman]

Totally understand. I’d try backing them up some. Not all bullets want or need to crowded to the lands. All mine justo. I’ve not found any hat needed to be close to the lands in my rifle

[Adam Van Camp]

The book says to load them to 3.290". I made a dummy round to test that length. I could not even get the bolt closed. That is when I measured the max length and seated 0.025" deeper. The IMR 7828SSC shot great with the same seating depth. This round is only going to be used to shoot Antelope, coyotes and prairie dogs. If I get to go for elk next year I will be using the Barnes TSX 160 grain.

[Muddydawg75]

I only use IMR 4350 for my 7mm mag.... I am always in the mid 60's..... I'd have to open my book to get specifics....

[Adam Van Camp]

So, here are the correct numbers for the IMR 7828SSC and Hodgdon H4831according to the Hornady book. H4831 starting load is 55.5 grains with a max of 65.0. I started at the 55.5 and loaded 0.5 grain increments up to 62.0. None of the shot well. The IMR 7828 starts at 60.2 with a max of 68.1. I started at the 60.2 which shot the 0.75" group, and loaded 0.5 grain increments up to 63.2 grains. The heavier the load the bigger the group got. The 60.2 and 60.7 was the best loads. It look like my gun doesn't like the hotter loads.

[JeffreyDeGraff]

Maybe try a different powder, or bullet, or seating depth. If the 2700fps velocity is on par with your 60.2gr load, then that would amount to a very expensive to shoot 7x57 Mauser. Definitely adequate for killing whatever game your after, just not what I would want or expect out of a 7mag.


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[tabascoman]

Hornady is also very conservative. I’d do a good ladder test and find the max load for your rifle. When I started all I had was a lee book I got with my loading kit. You should be upward of 3300fps with 65gr load. I’m running just over 3200 with my bergers at 64gr. And 2985 there about with the 63.5gr charge with my 162 amax

[Adam Van Camp]

Got to go shoot this load of 60.2 grains of IMR 7828 SSC behind the Hornady 139 SST through the Chrono this morning. The Chrono was set at 10 feet in front of the muzzle. Here is the results:
Average 2830 fps
Standard Deviation 23.71
True Muzzle Velocity 2836.61
Spread 54

FPS Ft-Lbs Power Factor
Shot #1 2796 2413.26 388.64
Shot #2 2833 2477.56 393.79
Shot #3 2850 2507.38 396.15
Shot #4 2841 2491.57 394.90

This should work for any Antelope and coyotes that I run across.

[JeffreyDeGraff]

Yes it should.


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