7 PRC and Magnum Powder

[jbseamus83]

I built a 7 PRC off of the Howa 1500 barreled action last year. I didn't get around to developing handloads for it and just used Hornady's Outfitter with the 160 gr cx this last hunting season. It shot well enough (around 1 moa).

I've now started developing some handloads. I started with H1000. I have a load that looks promising, but I'm testing a couple of powders with the 162 gr ELD-X. I loaded some loads with Magnum powder and shot a few of them. None of them are inside of 3 inch groups. Now, to be fair, I shot them after shooting about 25 rounds out of my rifle with the H1000.

I took 5-10 minute breaks between each 4 round group the whole day. But the Magnum did not want to group. I'm going to reload the same groups and go shoot them with a cool barrel, but I'm wondering if anyone has found a load they liked with Magnum powder. I also have 168 grams of ABLR bullets and 175 grams of gameking bullets to try at some point.

 

[Alpine01]

I built a 7 PRC off of the Howa 1500 barreled action last year. I didn't get around to developing handloads for it and just used Hornady's Outfitter with the 160 gr cx this last hunting season. It shot well enough (around 1 moa).

I've now started developing some handloads. I started with H1000. I have a load that looks promising, but I'm testing a couple of powders with the 162 gr ELD-X. I loaded some loads with Magnum powder and shot a few of them. None of them are inside of 3 inch groups. Now, to be fair, I shot them after shooting about 25 rounds out of my rifle with the H1000.

I took 5-10 minute breaks between each 4 round group the whole day. But the Magnum did not want to group. I'm going to reload the same groups and go shoot them with a cool barrel, but I'm wondering if anyone has found a load they liked with Magnum powder. I also have 168 grams of ABLR bullets and 175 grams of gameking bullets to try at some point.

I've been using H4831SC in my 7mm RM with a 150-gr CX. 0.54 MOA (max) after load development based on a total of 95 shots to date. I also tried H1000 when I was starting my load development but didn't get as good performance or group size. Shooting the factory Hornady CX loads initially yielded very poor grouping but I liked the bullet so I stayed with it. If you go from all-copper to bonded, then you shouldn't have accuracy issues. But going from bonded to all-copper requires a thorough cleaning otherwise you are likely to get poor accuracy results. How the barrel is fouled seems to make a difference.

 

[Darkside]

Clean your barrel real good.
And I’m guessing you are using 1st fired Horny brass?
Load 3 to 5 rounds each with the bullets you have an see if any have potential. If not change powder, I recommend
N- 560/565. For 7 prc.
Hope this helps.

 

[D4570]

Reloader 26

 

[jbseamus83]

I've been using H4831SC in my 7mm RM with a 150-gr CX. 0.54 MOA (max) after load development based on a total of 95 shots to date. I also tried H1000 when I was starting my load development but didn't get as good performance or group size. Shooting the factory Hornady CX loads initially yielded very poor grouping but I liked the bullet so I stayed with it. If you go from all-copper to bonded, then you shouldn't have accuracy issues. But going from bonded to all-copper requires a thorough cleaning otherwise you are likely to get poor accuracy results. How the barrel is fouled seems to make a difference.

I've been keeping an eye out for H4831sc for a little while. It's a bit hard to come by right now. The H1000 groups fantastic with 140 gr game kings in my 7mag. I have a load that is .5 inch all day and will give me even smaller groups if I do my job.

 

[jbseamus83]

Clean your barrel real good.
And I’m guessing you are using 1st fired Horny brass?
Load 3 to 5 rounds each with the bullets you have an see if any have potential. If not change powder, I recommend
N- 560/565. For 7 prc.
Hope this helps.

This is a great suggestion. I should have stopped and done that before starting with a whole new powder and testing. I cleaned it real good today. I don't have any of the N560 or 565 right now, but can get some. What grain bullets are you shooting with that? what kind of velocity?

 

[jbseamus83]

Reloader 26

If I could find some, I would be all over it. Everywhere is sold out and it's next to impossible to get hold of. This is the top powder I would like to shoot. H4831sc is right behind that. What I have currently is the H1000, Ramshot Magnum, N165, and just got some Accurate Magpro.

 

[Alpine01]

I've been keeping an eye out for H4831sc for a little while. It's a bit hard to come by right now. The H1000 groups fantastic with 140 gr game kings in my 7mag. I have a load that is .5 inch all day and will give me even smaller groups if I do my job.

Try shootingbot.com if you can't find it locally.

 

[bluegrassdan]

If I could find some, I would be all over it. Everywhere is sold out and it's next to impossible to get hold of. This is the top powder I would like to shoot. H4831sc is right behind that. What I have currently is the H1000, Ramshot Magnum, N165, and just got some Accurate Magpro.

Alliant stopped all production of certain canister grade powders for the reloading market back in 2024. Reloader 26 was one of the first to disappear from the shelves. If you have some, best hold onto it for special hunts. I have found N565 to get you pretty close to the same velocity and accuracy in the 7SAUM and 280ai.

 

[Addicting]

The H1000 groups fantastic with 140 gr game kings in my 7mag. I have a load that is .5 inch all day and will give me even smaller groups if I do my job.

That has nothing to do with this new rifle and shouldn’t be used as a reference at all. Each cartridge is unique. What works well in one could be absolutely garbage in another.

 

[mtmuley]

I've been keeping an eye out for H4831sc for a little while. It's a bit hard to come by right now. The H1000 groups fantastic with 140 gr game kings in my 7mag. I have a load that is .5 inch all day and will give me even smaller groups if I do my job.

Keep shooting this. mtmuley

 

[jbseamus83]

Alliant stopped all production of certain canister grade powders for the reloading market back in 2024. Reloader 26 was one of the first to disappear from the shelves. If you have some, best hold onto it for special hunts. I have found N565 to get you pretty close to the same velocity and accuracy in the 7SAUM and 280ai.

Thanks for the info. I can definitely find some N565

 

[jbseamus83]

Keep shooting this. mtmuley

Definitely not going to stop shooting it. I'm just also working to get a load that does that in my 7PRC.

 

[Hams42]

If I could find some, I would be all over it. Everywhere is sold out and it's next to impossible to get hold of. This is the top powder I would like to shoot. H4831sc is right behind that. What I have currently is the H1000, Ramshot Magnum, N165, and just got some Accurate Magpro.

My 7 Mag really likes H4831SC with 168 bergers. I however don't like the bergers.

Also I was also using RL26 for my loads until the powder stopped being made. Now I have a half pound that I have no use for.