7MM Rem Mag & H4831 with 160 Grain Partitions

[Tom1911]

I have settled on Nosler bullets for all hunting. I use 150 Ballistic Tips fpr deer, and they work better than advertised. I use 63 grains of IMR 4350, and with my Sako 7MM Rem Mag with a 24" barrel I get better than 3200 FPS with three-shot groups that can be covered with a nickel. But for elk, this load won't work as well as the 160 grain Partition.

I have old reloading data that shows 68.5 grains of H4831 as maximum with this bullet. I think this came from an old issue of "Rifle" magazine. I have loaded 67 grains of H4831 with 160 grain Partitions for well over 3100 FPS. This load shoots well in my rifle with absolutely no signs of pressure. I get just under MOA with this load. I know I could easily increase it if I thought it beneficial. I know deer die quickly when hit with this combo.

My question is why Nosler does not list H4831 powder with its 160 grain Partition bullet?


Happy New Year,

Tom[/i]

 

[fredj338]

Tom, probably because RL22, IMR7828 & H1000 offer higher vel. w/ good accuracy & 1005 load density. I like H4831sc for 140gr but when you move up go to a slower powder. H4831 is very accurate in my 7mag but going to slower powder gives me another 100fps w/ same accuracy.

 

[Tom1911]

frej338,

Witht he powders you've, is it possible to achieve velocity of 3100 FPS or better with 160 grain bullets?

Of the three you listed, which one is your preferred powder for use with 160 grain bullets?

Thanks,

Tom

 

[fredj338]

My rifle likes RL22 & IMR7828 equally well, under 1MOA for three shots. IMR7828 gives a bit more vel. A buddy of mine swears by H1000, your rifle will tell you. H4831sc is very good but I think it starts to run higher pressures for given vel. when you start pushing 160-175gr bullets. I get about 3000fps w/ H4831sc, and easily get to 3100fps w/ the others.

 

[roysclockgun]

What about MagPro with the 150gr bullet in 7RemMag.
The only experience that I have had with MagPro was using the 140gr AccuBond and with that bullet. MagPro and IMR7828 gave very similar results, using equal amounts of propellent. I stuck with IMR7828, because it filled the case better than did MagPro. Comments?

 

[john-brennan]

Retumbo or if you can find it H870 are the best in my rifle, i could not get over 3050fps with H4831 with a 24'' tube. but get over 3100fps with the two metioned.

 

[Tom1911]

john-brennan,

The twist of my rifle (9.5:1) might have something do with the velocity I am able to chrono. However, I do have older reloading manuals that list my load of 67 grains of H4831 with 160 grain bullets as well under maximum.

I was able to get over 3200 FPS with 160 grain Hot Cores, but that was really pushing it pressure-wise.

I do think there are powders available that will enable the 7MM Rem Mag to achieve its potential. When it was introduced, it was a long range rifleman's dearm. I still believe it is the single best cartridge with which to hunt all Rocky Mountain game. However, one needs to handload to wring out its true potential. With 3100 FPS and a 160 grain AccuBond, it will shoot straight enough to take any elk at reasonable distcances, considering the body size of such animals.

I have heard Retumbo (acronym?) is an excellent powder for the 7MM Rem Mag with heavy bullets. I hope to give it a try.


Good luck,

Tom

 

[JD338]

Tom,

You might want to try RL22 as Fredj338 mentioned. You may not reach 3100 fps, but you should get great accuracy.
Also, use the Federal GM215 primers.

Regards,

JD338

 

[Tom1911]

JD338

The highest velocity I achieved with my 7MM Rem Mag & 160 grain bullets was with RL22. I was working up loads, and at what I considered max for my rifle was just over 3200 FPS. But because I can load 67 grains of H 4831 & be well under max for my rifle, I see no reason to change. This load gives me just over 3100 FPS w/o even a slight indication of pressure! But I might change if accuracy is better with IMR 4350. BTW, I have older material that indicates more than 60 grains of IMR 4350 is max with 160 grain buillets. I dunno though, I would have to work up & see where it goes. Saftey followed by accuracy are my primary concerns.


Take care,

Tom

 

[fredj338]

Tom, I think you'll find 4350 too fast for best results in the 7mag. IMR4831 is the fastest I would go. Otherwise your perf. will be close to a handloaded .280, about 2950fps w/ a 160gr bullet. I can get 2850fps from my .280, 23"bbl. & 7.25# ready to hunt weight.

 

[Tom1911]

fredj338,

I use IMR 4350 for 150 grain bullets now with stellar results. I have some older reloading data that indicates 3100 FPS with IMR 4350 & 160 Noslers.

In my rifle at least, 3100 FPS with 160 grain bullets is not difficult. However, since I am primarily motivated by accuracy, I would accept reduced velocity. IMR 4350, at least with 150 grain BT bullets, is astoundingly accurate. This is the primary reason I would try IMR 4350.

What have you heard about IMR 7828? I was once informed that this powder was created for the 7MM Rem Mag. True? Apparently this powder will produce high velocity with decent accuracy in the 7MM Rem Mag.


Take care,

Tom

 

[FOTIS]

H1000 and RL 22 game me the best results.

 

[Tom1911]

POP,

Thanks. I have used R22 with good results. I have yet to try H1000.

I think I am going to try R22 with 160 Partitions just to see what happens.

What receipe do you use? I worked up a max load that I think was 66 or so grains of R22 with 160 grain bullets. I might not have the charge correct, though as I'm relying on memory.


Take care,

Tom

 

[jdmason480]

Tom,

I've been using 65 grs of RL22 with the 160gr AB's with good results. The recipe is from the from the Alliant Powder website with a published velocity of 3,075fps MV.

jd

 

[Tom1911]

jdmason480,

Your velocity is just about equal to what I am getting. How's the accuracy with your load?


Thanks,

Tom

 

[jdmason480]

Tom--I have shot MOA groups with this load. Last time I was out, all three shots in the group were at the exact same elevation with one shot left about 0.5" and one right 0.5". I don't keep meticulous enough notes to be definitive. But, the RL22 shoots as tight as IMR4350 in my gun and tighter than IMR4831 for whatever reasons.

Please let us know what your experience is.

jd

 

[Tom1911]

jdmason480,

Thanks for your info. Bith IMR 4350 & 4831 are renowned for accuracy. For RL22 to be in their league is impressive.

What rifle you shootin'? I shoot a Sako with the old style action, & it is one of the most accurate rifles I have ever fired. Remingtons will shoot like nobody's business as well. In fact, with modern manufacturing techniques, as long as good components are used, most guns are now producing incredible groups!


Good shootin',

Tom