Found good load for 7RUM

[7stw]

I started a thread a little while back in reference to load info for 7rum and 140 bullets. Well I think I have arrived at a suitable load. The result of yesterday's shooting was .498 groups at 200 yards and in the 3's at 100. Part of it was a bedding issue in the forend. I had tried RL22 and 7828. I was not getting the load density with those two but they were fast. (3406 ish) with low ES. So I decided to work with H1000. my load was 96.2-H1000- 140 partition. I also tried Accubonds and Interbonds. The best of the bunch was the Partitions, which I have no problem with. Nothing walks away from a partition. I did not not chrono that load yet. I can go to 98 grains, but will suffice to the accuracy if it changes. Recoil was not as sharp with the 1000 as was the recoil with 22 and 7828. The barrel is really shaping up now. It cleans very easily, and doesn't foul quite as quick. I baby it and don't overheat it EVER. I tried N170 , but feel that it is too slow for 140 bullets. May try that powder with 168's or 160's. Primarily I want to shoot 140's in this gun. Any body got any load info to share? I am still learning on this one. Thanks. AIM SMALL, MISS SMALL, lightbulbgun) 7STW. (p/s This is a Remington CDL)

 

[Bigd7378]

7stw, I have a custom winchester model 70 classic stainless with a 28" barrel. These are some of my loads, all loads use neck sized brass, federal 215 primers and 140gr barnes ttsx bullets. All loads are safe in my rifle, all of the brass is on it's fifth load with snug primer pockets still. 50bmg and rl-50 are thru a drop tube.

Alliant rl-25 96.0 gr 3656 fps .25"
Retumbo 99.0 gr 3651 fps .5"
H50bmg 108.0gr 3535 fps .5"
Alliant rl-50 108.0gr 3628fps .25"

I might try a little more powder with 50 bmg and rl-50.
Can't wait to try the new rl-33.

 

[7stw]

7stw, I have a custom winchester model 70 classic stainless with a 28" barrel. These are some of my loads, all loads use neck sized brass, federal 215 primers and 140gr barnes ttsx bullets. All loads are safe in my rifle, all of the brass is on it's fifth load with snug primer pockets still. 50bmg and rl-50 are thru a drop tube.

Alliant rl-25 96.0 gr 3656 fps .25"
Retumbo 99.0 gr 3651 fps .5"
H50bmg 108.0gr 3535 fps .5"
Alliant rl-50 108.0gr 3628fps .25"

I might try a little more powder with 50 bmg and rl-50.
Can't wait to try the new rl-33.

Thanks for the reply. Have you ever used Vihtavouri n-170 before with 140's? I have about 3 lbs of this stuff. I am told it is about like Retumbo in burn rate. I could be wrong. I have tried some loads that KNOW are safe. No pressure. Any thoughts? 7STW Thanks. lightbulb

 

[Bigd7378]

7stw, I have 4# of viht n170 have not tried it yet. I have been trying to get some viht n570 as it looks like this might be a player. Maybe I will give viht n170 a try. I am really getting excited to try the new alliant rl-33. Alliant powders seem to work better for me. Only problem is rl-25 leaves to much empty space and rl-50 is so compressed, even thru my 8" drop tube. So as you can see rl-33 is looking good to me

 

[7stw]

7stw, I have 4# of viht n170 have not tried it yet. I have been trying to get some viht n570 as it looks like this might be a player. Maybe I will give viht n170 a try. I am really getting excited to try the new alliant rl-33. Alliant powders seem to work better for me. Only problem is rl-25 leaves to much empty space and rl-50 is so compressed, even thru my 8" drop tube. So as you can see rl-33 is looking good to me

I am told that n170 and n570 are the same burn rate, but the500 series of powder is" high energy" what ever that means. I know this stuff is usable , but can not get good info on it. I feel safe using Retumbo load data, but always watch for anything weird, or tight. One thing about it is that that muzzle flame is intense. I am, or haven't gotten any signs of pressure at all. Easy extraction, easy resizing, round primer edges. I just would like to utilize it, rather than see it go to waste. And I really do feel like it will yield decent velocity as well. I tried a load of H1000, 96.3 to be exact this past Sunday and it yielded a .496 group at 200. And at 100, it was in the 3's. Velocity unknown at this point. Getting this thing to shoot is not as easy as my STW's, so any info is good info. I have a 300 ultra, and that was easy to get it to shoot. Two powder attempts, and settled with RL22. In the 7rum, 22 leaves to much air space. Velocity is good, but I feel like it is on the edge. RL22 is a temp sensitive powder, and on a warm day, it could be trouble. Any thoughts? 7STWlightbulb

 

[Bigd7378]

I have some quickload data that someone gave me. Don't know how accurate quickload is. Any ways it shows viht n170, viht n570, retumbo and rl-25. All loads are with 140gr accubonds in 26" barrel and 63,000 psi. Like I said I don't really know how accurate it is. But here is some data
Viht n170 93.6 grs 3200
Viht n570 95.3 grs 3327
Retumbo 94.5 grs 3264
Rl-25 87.6 grs 3236

 

[meatyrem]

Hey Fellas,
I was wondering if anyone has tried us869? this is what im going to try. probably better with the heavier bullets

 

[Airgunner7]

Don't try too many loads or you will wear out the barrel by the time you find the ideal load.
As I understand it, the barrel life is 300-1000 rounds. After 200 rounds in my Sendero I have gotten a few 3s but, most groups average 7's. I think the freebore is the limiting factor....even with 180 VDLs I am .250" away from lands.

 

[7stw]

Don't try too many loads or you will wear out the barrel by the time you find the ideal load.
As I understand it, the barrel life is 300-1000 rounds. After 200 rounds in my Sendero I have gotten a few 3s but, most groups average 7's. I think the freebore is the limiting factor....even with 180 VDLs I am .250" away from lands.

Yea, I am WELL aware of the abbreviated barrel life, and the count is still low at this point. I NEVER shoot it hot, and keep it clean. I am close to settling on a load, as I know the consequences otherwise. I have considered even selling it. I have a few other " fast " sevens, and the RUM was just a curiosity thing, that all things being equal, I would not do again. My STW's will shoot circles around it. But thanks for the info. gun)lightbulb AIM SMALL, MISS SMALL, 7STW

 

[Airgunner7]

No problem, it is a very curious beast. I was disappointed with my groups until had several 1800Y hits at a local mile shoot. I think I was the only guy without a muzzle break, witch in my mind is a hunting rifle.
Even with some regrets with the freebore I now appreciate it for what it is-one power hungry-powder eating 7.


I have a custom Pacific Tool reamer with half the freebore just begging to be used when this barrel goes..... More velocity and accuracy...oh boy.

 

[mhiltz]

Hey Fellas,
I was wondering if anyone has tried us869? this is what im going to try. probably better with the heavier bullets

That is what I use, and I love it with the heavier bullets of course. People say it is way too temp sensitive, but I have had no problems with it in the cold or hot temps, and I load mine hot, because that is where it likes them. The only other powder that I have found that might be fairly comparable to US869 is the N570. I haven't tried any yet, but plan on it soon. It would be a benefit to you to try the US869 in your 7RUM. (with 168gr or 175gr bullets)