7mm PRC & N570

[TxLite]

I have a load I like with 168LRX 67.5g RL26 2974fps, but can't find RL26 anywhere, so looking at switching to N5??, curious what folks would recommend as the best "similar" powder N560, N565, or N570? I have no experience with any of those.

I agree with the post above. Of the N5XX powders the N565 is likely the best suited for the 7prc. That being said I’m having pretty good results with the N570. Just have to use an electric toothbrush to settle the powder.

If you’re not hung up on the N5XX powders, Retumbo might also be worth a shot. It shoots fantastic in my 7 rem mag. H1000 also seems to be a staple for the prc.

 

[philcox]

I agree with the post above. Of the N5XX powders the N565 is likely the best suited for the 7prc. That being said I’m having pretty good results with the N570. Just have to use an electric toothbrush to settle the powder.

If you’re not hung up on the N5XX powders, Retumbo might also be worth a shot. It shoots fantastic in my 7 rem mag. H1000 also seems to be a staple for the prc.

H1000 didn't seem to get the velocity I wanted with the 168 LRX. I am in Cali, so have to shoot mono. Kind of weird to me that RL26 gave me 100fps more velocity than H1000. I tried Ramshot Magnum, but groups not as good as RL26 at similar velocities. I may just shoot up my RL26, and if I can find more before I need it, use that, and if not, give N565 a shot. It's a bit cheaper than the Hogdon stuff, and if it works as well. Time will tell. Thx for the info. I am not much into the "toothbrush" method at this point. I hope to get lucky and find some RL26 or a Leprechaun with a pot of gold ...

 

[Gadjet]

I agree with the post above. Of the N5XX powders the N565 is likely the best suited for the 7prc. That being said I’m having pretty good results with the N570. Just have to use an electric toothbrush to settle the powder.

If you’re not hung up on the N5XX powders, Retumbo might also be worth a shot. It shoots fantastic in my 7 rem mag. H1000 also seems to be a staple for the prc.

It’s looking like you’re having some pretty good luck with that shorter barrel. What is your coal?

 

[TxLite]

It’s looking like you’re having some pretty good luck with that shorter barrel. What is your coal?

3.3375. Obviously with bullet variations the coal is kind of useless though. Cbto is much more repeatable. These end up at 2.5935

 

[Gadjet]

3.3375. Obviously with bullet variations the coal is kind of useless though. Cbto is much more repeatable. These end up at 2.5935

Thanks for the info. So they fit in a factory Tikka mag without any issues?

 

[TxLite]

Thanks for the info. So they fit in a factory Tikka mag without any issues?

Yup. No problem fitting in mine but they’re about as long as you can get them. Thought I’d need the mountain tactical mags but ended up selling them and staying with the Tikka mags.

 

[Gadjet]

Yup. No problem fitting in mine but they’re about as long as you can get them. Thought I’d need the mountain tactical mags but ended up selling them and staying with the Tikka mags.

Perfect! I’ve been following your info on loads. I’m waiting on my 20 inch 7PRC to be built by UM. I’m hoping to get somewhere around 2900fps with a 180 grain ELDM.

 

[TxLite]

Perfect! I’ve been following your info on loads. I’m waiting on my 20 inch 7PRC to be built by UM. I’m hoping to get somewhere around 2900fps with a 180 grain ELDM.

That would be a sweet combo. Make sure to post results

 

[Bleeb]

I agree with the post above. Of the N5XX powders the N565 is likely the best suited for the 7prc. That being said I’m having pretty good results with the N570. Just have to use an electric toothbrush to settle the powder.

If you’re not hung up on the N5XX powders, Retumbo might also be worth a shot. It shoots fantastic in my 7 rem mag. H1000 also seems to be a staple for the prc.

I can't find the RL26 pixie dust anywhere, so I am ordering a few pounds of N565 to try with the 175gr ABLRs out of my 22" Proof barrel. After running a few scenarios through GRT, it seems to bee the best balance between case fill, burn, and velocity. I'm sure it'll be accurate. Vihtavouri says it splits the difference between N560 and N570, but is closer to N570.

 

[SemiProRoadHunter]

My 20” was launching 180eldms at 2965 with 73gr of n570, 5.7 sd with a 10 shot string No pressure signs yet.

 

[TxLite]

My 20” was launching 180eldms at 2965 with 73gr of n570, 5.7 sd with a 10 shot string No pressure signs yet.

Wow that’s great velocity.

 

[SemiProRoadHunter]

Wow that’s great velocity.

I think I lucked out with a fast barrel. I’ve seen other peoples loads going 1-1.5 grains higher with less velocity.

 

[TxLite]

I think I lucked out with a fast barrel. I’ve seen other peoples loads going 1-1.5 grains higher with less velocity.

Yeah you’re 130fps faster than my 18” with a 180 hybrid at 73gr. I’d definitely be happy with that

 

[Bleeb]

I just ran N565 in my 7PRC, 22" proof barrel, using Nosler 175gr ABLRs. Best results were with 69.7gr at ~2924fps with an ED of 4 (five shot is a small sample size, but still.....). Group was a touch over under .75", but it was gusty. 69 gr. opened up to about an inch, at ~2887fps with an ES of 12.

I'm going to pull some 175gr ELD-Xs I handloaded with 71.1gr Staball HD (~2900fps) last fall and see how they run with N565. I have 8#, so I sure hope it works, LOL!

I also got some Magpro at 69.3gr, which also shot well, albeit a tad slower at 2850fps. As recommended by Nosler, I seated the ABLRs too deep - 50 thou of the lands. I would guess that I'd get comparable speeds if I poked them out and added a few tenths more pow pow.

 

[philcox]

I finally did a bit of initial testing with N565. Ended up with 70.5g N565 running 3010 out of a 20" barrel. I have not yet group tested, but am happy I now have this as a test when my current batch loaded with RL26 run out.

 

[leclairk]

Playing around with GRT today and I am coming up with some very different numbers than what was experienced in the field. I figure there may be a little velocity gain with the suppressor (20ish fps?), but it is showing about 140fps difference from what I experienced. None of my loads showed signs of excessive pressure, but it is showing that in order to hit the velocity I achieved, I'd need to be about 3 grains higher than actual. I honestly don't know that you could even get an extra couple grains in there. Even at 73 and 73.5 I have to give it a good 10-15 seconds with the electric tooth brush to get the powder to settle far enough to seat the bullet without crunching powder.

Overall it shoots great. Going to load up a bunch at 73.0 and see how they hold up over time.

73.0 @ 2695 - actual @ 2833
View attachment 692526

75.8 @ 2835
View attachment 692533

A bit off topic but how did you get load data for the 7 PRC in GRT? Mine doesn’t show up in the database.

 

[TxLite]

A bit off topic but how did you get load data for the 7 PRC in GRT? Mine doesn’t show up in the database.

I found a 7prc file on discord. I’d also modified 7 blaser on GRT and got close but the 7prc discord file has been accurate for me

 

[Shrapnel993]

I found a 7prc file on discord. I’d also modified 7 blaser on GRT and got close but the 7prc discord file has been accurate for me

Following all this great information closely! I too am working up a load for my 7PRC and was wondering if you can share or let me know where I can get the 7PRC file for GRT? The tool has been really accurate for me but I've never built a cartridge profile from scratch.

 

[philcox]

I am using GRT to look at some prospective loads. The interesting thing is that every load I have is "overpressure" in the GRT tool. I was hoping someone with QuickLoad could do an analysis on the load I have so I could compare. If you have QL and are willing, send me a PM, and I'll shoot you all the info I have on the load that I am putting into GRT.

Thanks

 

[TxLite]

I am using GRT to look at some prospective loads. The interesting thing is that every load I have is "overpressure" in the GRT tool. I was hoping someone with QuickLoad could do an analysis on the load I have so I could compare. If you have QL and are willing, send me a PM, and I'll shoot you all the info I have on the load that I am putting into GRT.

Thanks

A lot of folks would be surprised to see the actual pressures they are hitting. I think a good chunk of handloaders are exceeding Saami without realizing it. Others (me included) realize it and monitor for signs that it is getting too high. Stiff bolt lift, blown primers, etc.