Best powder for 7 Rem Mag

[sidreilley]

Just got a new rifle in 7 Rem Mag and I don't have any experience with the 7 Rem Mag so I'm starting from scratch as far as powder goes. I plan to use 160-170 gr. bullets, probably Hornady SSTs or A-max and am wondering if anyone has any recommendations for a load that works well for them with these or similar bullets? In doing a quick search of Hogdon's site, I noted that Rotumbo produces as high a velocity as anything listed but did it with considerably less powder. I take that to mean, perhaps incorredtly, that cases and barrels may last longer too and that's a good thing. Any thought/tips appreciated. Oh, the rifle is an Weatherby Mk V Accumark with 26" tube.

 

[Nodak7mm]

With 162 Amaxes, I am driving them at a nice 3050-3075 with RL-22. Great pwdr for me in my 7mmRM with a 27" Brux barrel. Like the load so much, I went and pick up the other 5# jug of that powder lot..

Rod

 

[MrMajestic]

With 162 Amaxes, I am driving them at a nice 3050-3075 with RL-22. Great pwdr for me in my 7mmRM with a 27" Brux barrel. Like the load so much, I went and pick up the other 5# jug of that powder lot.

Rod

+1 for RL22 and the A-Max. Just be aware of the temperature stability concern.

 

[sidreilley]

I forgot to mention that I prefer temperature stability as I'm looking for 1 or 2 loads to use year round for hunting. Thanks for the imput.

 

[chuckles]

Try H4831 I believe it is/was the powder used for the Sierra Accuracy load for their match bullet in this weight range. It is an extreme powder and should be less affected by ambient temperatures.
Worked well for me-shot a 200-10x in the Leech Cup in my 7 Rem Mag.
Chuck

 

[Joe C]

I used to use 80g of Accurate 8700 with a 140g Nosler BT that shot consistently minute of deer out to 669 yards (my longest kill with my Ruger M77 MKII Stainless in 7mag). It also shoots 5 shot groups into under 1" with regularity. Alas, they no longer make that powder and I wasn't smart enough at the time to buy up tons of it...

So this question is one I'm enjoying reading as well! Thanks for the good tips guys!

 

[Nodak7mm]

I forgot to mention that I prefer temperature stability as I'm looking for 1 or 2 loads to use year round for hunting. Thanks for the imput.

You mean like this?

Load developed for the sole reason of collecting vension during Oct/Nov. No temp problems ...... for the load anyways... ;D

Where I live there is no year around load. It's either warm or cold and the load I shoot in the above rig is for cold wx. But I feel that way with any powder considering the temp swings I experience. So I will state emphatically, I dont believe in such a thing as a "yr rd load." Or have belief in the marketing slogan "temp insensitive" powders... Load for ambient conditions.......



Rod

 

[fastcars69]

4831 has always been good in my Remington 700 ADL 7mm mag.

 

[wapiti25]

Rem 40x in 7mm Rem Mag was tested with 168 Sierra MK using IMR 4350.

 

[yukonal]

I had a hammer load with 160 AccuBombs and RL-25. Then came winter shooting, and everything changed...read...the groups doubled in size. Or more. Back to the drawing board.

No one has mentioned H 1000. No love for it?

 

[Exocet]

Another recommendation here for H4831, either regular or the SC version. Very accurate with the heavier bullets out of my 700 Sendero or 700 BDL. I like the 168 MK's especially.

 

[4xforfun]

The 7mm and H1000 were made for each other!! That being said, I ran into my FIRST 7mm Rem Mag ever that didn't like H1000 this winter. It was OK, but RL 25 worked better....168 VLD in a Savage 116. I have a couple of guns that shoot equally well with either H1000 and RL 25, but I am shooting either 168 or 180 JLK's out of them. The only reason I used RL 25 was speed. The RL 25 was SILLY fast. These (rl 25) were late fall deer hunting loads. i would do the H1000 if I were to shoot in differing temps and did not want to tweak the load.

Good luck,
Tod

 

[markm87]

No one has mentioned H 1000. No love for it?

We're using it... but 7 mag is on the back burner for now. Working on 300WM.

 

[jimbires]

I use a 160 accubond , with 66.0 grains of RL22 , and a fed215 primer . this gives me 3000 FPS with a 24"bbl . Jim

 

[Jazz]

I use H-1000 and 162 amax and 168 Berger at 70.5-70.7 grains. It was load that Best of the West was using and it worked in my rifle.

 

[4xforfun]

i just ran some testing today on RL-22

info:
browning a-bolt 26" barrel
Amax 162gr.
best load was at 65.0gr and 3 shot average on the chrono was 2915fps

.3moa at 100 yards

another sweet spot was at 66.0 gr with a 3 shot average of 2967fps

.35moa at 100 yards


not sure why i got 2 nodes within 1 grain apart but it is what it is.
there was no wind & shooting conditions were ideal.

I would go back to 64.5 and go to 66.5 in 1/4 grain incraments. I'll bet that this is ONE BIG NODE, not two nodes 1 grain apart.

 

[Britto87]

I currently use 73 grains of Retumbo in front of 168 gr Berger VLD's in my Remington Sendero 7mm Rem Mag. The speeds average 3130 fps and shoot under 1/2 MOA at 100yds with 3 shot groups. I would start out a few grains less and then work up since no two guns are the same.

 

[XTR]

Those two groups by them selves don't tell you anything about whether you are in a node or not, they are two tight 3 shot groups, but that is all they tell you. If you understand how to determine OCW you should understand that group size in the OCW ladder means little.

You are looking for dispersion from the point of aim of the group. What will tell you if those two groups are in a node is the groups on both sides of them.

 

[XTR]

Looks like you may have a node 65.5 and 66.0. The POI of both of those groups is almost exactly the same. 65.0 was lower by a noticible bit but you also have what looks like you have a nice node from 64.0 to 65.0. Notice that all three of those groups are w/i a bullet diameter of the same vertical plane? and you are only talking about 0.6 inch of horizontal. I'm betting that's your node.


I usually do my OCW in 0.3 gr steps the first time and 0.2 gr to dial it in. Try it again starting at 64.0 and go up to 65.0 in 0.2 gr steps. I bet you find three loads that are on top of each other. At that point slight variations in powder make almost no difference in your POI till you get out to 1000 yards and slight variations in MV will give you 10 inches of vertical, but you've still eliminated a variable in the barrel harmonics (if you buy the voodoo)

 

[XTR]

thanks XTR, will do.

i also plan to repeat this test with H1000 and then test H4831sc.

my reference link is here:
http://optimalchargeweight.embarqspace.com/#/ocw-instructions/4529817134

If you read all of what he's written in that link you'll see that he also says not to get too distracted by group size at this point. You can dial the group in with seating depth. That's the reference I use.