7mm mag powder

[KRasmussen]

I am currently in the hunt for a new powder for 7mm rem mag. I did work up some loads last fall and I am not very happy with the results. Now I must say accuracy was awesome but velocity was well below what was published. I was using IMR 4831 pushing Barnes MRX 140gr at just over 2800fps. All of the data I had compiled I might as well toss as Barnes has discontinued the MRX line. So, I will go to the new LRX in 168gr. Before I go any further ya'll need to know I am in Cali and have to use lead free stuff and I feel Barnes is the pack leader. I am not able to shoot any of the other brands with lead. I am looking at other powder options, in particular RL19, 22 and 25. Does anyone have any experience with these in 7mm, and are you happy with the results?

 

[Drake4]

I shoot RL-22 through my 280AI at pretty close to 7-mag speeds. It has been great for me.

Also give Retumbo a try.

 

[tarheel]

I am currently in the hunt for a new powder for 7mm rem mag. I did work up some loads last fall and I am not very happy with the results. Now I must say accuracy was awesome but velocity was well below what was published. I was using IMR 4831 pushing Barnes MRX 140gr at just over 2800fps. All of the data I had compiled I might as well toss as Barnes has discontinued the MRX line. So, I will go to the new LRX in 168gr. Before I go any further ya'll need to know I am in Cali and have to use lead free stuff and I feel Barnes is the pack leader. I am not able to shoot any of the other brands with lead. I am looking at other powder options, in particular RL19, 22 and 25. Does anyone have any experience with these in 7mm, and are you happy with the results?

Not personally, but Nosler data with the 140 and 160 weight bullets uses the 19, 22 & 25 in the faster formulas, so they must think pretty highly of them. Their 140gr offerings with both 19 & 22 give speeds ranging from 3160 to 3340. The 160's using 19, 22 & 25 list speeds ranging from 2868 to 3066. The only 160gr load exceeding the 25 was Mag Pro powder and it was only negligibly faster.

 

[gundog]

I like RL-22. It's very consistent.

 

[Taxidermynut]

I have had really good luck with 7828 and h1000. 70 gr. 7828 puts me under a 1" at 2000yds with 160gr. acubonds, muzzle velocity of 3230fps. I would start out around 66 or 67 gr. 70 is pretty hot. 70 gr. of h1000 worked best also, but was only around 3050fps. Either works great with whatever bullet I have tried, just have to try a couple different loads to see were the best accuracy is at. The reloader line of powder is great powder, just a little more temp sensitive. If you don't have big temp swings it should be fine.

 

[1_pointer]

I have had really good luck with 7828 and h1000. 70 gr. 7828 puts me under a 1" at 2000yds with 160gr. acubonds, muzzle velocity of 3230fps. I would start out around 66 or 67 gr. 70 is pretty hot. 70 gr. of h1000 worked best also, but was only around 3050fps. Either works great with whatever bullet I have tried, just have to try a couple different loads to see were the best accuracy is at. The reloader line of powder is great powder, just a little more temp sensitive. If you don't have big temp swings it should be fine.

That's some pretty good shooting!!!

 

[thecrittergitter]

I too am a fan of RE-22. Have also had great luck with RE25 and H1000.

All i've been shooting is the barnes ttsx in 160's so you should give that a try.

Think i'm shooting 65 grains of powder.

 

[belly-deep]

RL-22 is a great powder in a 7mm Rem Mag, however it will lose quite a bit of velocity when the temp goes down. If you're going to be shooting in consistent temperatures, it is definately worth a look.

I've heard good things about RL-25 for heavier bullet weights as well.

I'd also look at IMR 7828, H1000, and Retumbo. They are all much less temperature sensitive than RL-22.

 

[belly-deep]

160gr. acubonds, muzzle velocity of 3230fps.

If thats a 7mm Rem Mag you better wear safety glasses. That puppy is gonna blow one of these days.

 

[Blacktailbc]

For the 140's, I have had excellent results with IMR 4350 . For the 160's, H4831 and
H-1000. R-22 is also good, but temperature sensative.

Right now I am shooting 140 accubonds, 65 g. of IMR-4350.

 

[fishing4sanity]

Another vote for RL22. My son has a Howa 1500 in 7 Rem Mag, he did a lot of experimenting and chose the RL22. He shoots Berger VLDs, not sure if those are legal or not in Cali. He had some trouble getting his velocities up to those in reloader manuals until he increased his COL, now his gun is a tack driver.

 

[Taxidermynut]

Not as hot as you would think. It is showing little signs of pressure, but nothing to worry about. I've shot loads you buy off the shelf that show more signs. Everygun is not the same. If I shot it out of my little brothers remington he might be in trouble. Thats why I said I would start a lower charge.

 

[belly-deep]

Not as hot as you would think. It is showing little signs of pressure, but nothing to worry about. I've shot loads you buy off the shelf that show more signs. Everygun is not the same. If I shot it out of my little brothers remington he might be in trouble. Thats why I said I would start a lower charge.

Dude, you're 6 grains over book max. Quit bullshitting yourself. The 7mm Rem Mag is not a cartridge capable of 3200+ fps with a 160gr bullet without getting into dangerous pressures.

If that isn't enough reason to stop, the 7mm Rem Mag, along with the .243 Winchester, is a cartridge that for some reason, is subject to big pressure swings from shot to shot.

You need to call Nosler and talk to their ballistics experts before you continue with that load.

 

[Gunner46]

I got pretty results in the 165 gr range with H4831.....stretched the load data recommendations, a bit, but never saw any pressure problems.

 

[KRasmussen]

Another vote for RL22. My son has a Howa 1500 in 7 Rem Mag, he did a lot of experimenting and chose the RL22. He shoots Berger VLDs, not sure if those are legal or not in Cali. He had some trouble getting his velocities up to those in reloader manuals until he increased his COL, now his gun is a tack driver.

I am shooting the same gun. Love it. Unfortunately Berger's are not allowed for hunting in most of Cali. There are a few areas left that do not require lead free but they are in the extreme northern parts, where I dont have the opportunity to hunt.

It looks as though RL22 is the overall winner with the exception of the temp swings. I guess it gonna be as much of a crap shoot as I thought. I will load and try some with Retumbo, which I have, and maybe see if a few friends here have some 22 or 25 that I can try.

Do you recall what COL was in the gun? IIRC mine was 3.290 and that is .050 off the lands

 

[BuzzH]

I've not tried RL22 in the 7mm, but I had no luck at all with H1000 or IMR7828. I still have nearly full pounds of each. I've never had real good luck with either of those. Sure sounds like many do though.

IMR 4831 has worked really well in just about everything I've tried it in.

 

[Taxidermynut]

got to love people that seem to know more about your gun and loads than you do. What makes you think that the max the put in some book is the max you can be safe with? Do you think that they would even get close to a true max in a published book? If you do you are up in the night.

Oh well don't really give a rats A$$ if you think I should quite shooting it or not. I'll keep watching for case pressure signs, instead of beliveing what some book says

 

[BuzzH]

...rock on, nobody cares.

I'd think if you were even seeing "little signs of pressure" you'd take that into consideration.

But, if it suits you and your good with it, thats all that matters.

Personally, I've never found high pressures, max loads, highest velocity, and accuracy to cross the same path...but I'm not quite getting under 1 inch groups at 2000 yards either.

 

[belly-deep]

got to love people that seem to know more about your gun and loads than you do. What makes you think that the max the put in some book is the max you can be safe with? Do you think that they would even get close to a true max in a published book? If you do you are up in the night.

Oh well don't really give a rats A$$ if you think I should quite shooting it or not. I'll keep watching for case pressure signs, instead of beliveing what some book says

Unless you're using electronic means to measure pressure, you know very little about the gun yourself.

That is a fact. Modern ballistics labs have proven that traditional pressure "signs" are actually of very little value. Hard bolt lift, case life, case head expansion, etc are all very poor indicators of a load that has high pressure. Many of those traditional "signs" don't show up in all rifles, or if they do show up, the load is well over maximum.

Which brings up another point. You obviously don't know what "maximum" actually means when it comes to loading. Your statement "do you think they would even get close to a true max in a published book" tells me that you think maximum is when a gun blows up. That is not true. Maximum is the pressure established by SAAMI, and it is a the safe working maximum for a load. A load beyond maximum doesn't blow up a gun on the initial firing. Instead, repeated firings over maximum fatigue the metal until eventually something breaks. In other words, just because you've fired a load 10 or 100 or 500 times, that doesn't mean the next time you pull the trigger the gun won't blow.

 

[----]

The load I'm using is 66 grains of RL-22 with the 160 grain accubonds. I want to say it's right at 3000 fps but I can't remember if that's this load or the factory stuff I was using.

I'm curious about the temperature swings you guys are talking, I'll have to go out and shoot it on a really cold day soon.