Vihtavuori N570 in 7mm Rem Mag

Hi everyone.

I'm just wondering if anyone has tried N570 in their 7mm RM? I have a couple of pounds of this and thought about trying it. If anyone has tried it, could you please share your experience and/or load data just so I have something to go by? Vihtavuori does not show any load data for the 7mm RM on their website with this powder and I'm not having much luck with searches. I'm thinking about starting at 66gr and slowly working up from there but I want to be sure. If I'm barking up the wrong tree with this powder, please don't be afraid to tell me.
I do have a few other powders to try (Retumbo, H1000, IMR7828) but would like to try the N570 just to see.

I will be shooting an accurized Rem 700 with a Jury 8 twist, 28" barrel. Barrel is broke in and has roughly 70 rounds down it now.
The bullets are Berger 180 VLD Hunting. I have 400 or so of these so thought I'd try to use them up first.
I did go with the faster barrel to try 195 Elites and will try them after I burn up the 180's, if I can get them to shoot.

Thanks

This is from my testing that I did in my 7mag. I posted it on LRO and screen shot it instead of retyping. One of the things I was told was N570 works best out of fireformed brass, and belted magnums will grow considerably. I was much faster shooting N570. I would recommend a 28 inch barrel for retumbo or N570 (which you have). I hbn coat my bullets so I use more powder o. Average 1-2 grains more because of hbn being extremely thick. I never worked up to pressure with N570 but I was using adg brass as well and had 70+ fps gain in velocity.
I would start ladder based off retumbo and work up to finding pressure.

I have heard people complain loading with N570 but I love using it. Each granule is 1/10 of a grain so getting perfect charges is easy. Just go low and trickle up.

My max load with retumbo before hbn coating was 71.5. (Slight primer swipe). Start low work up like always and be careful.

I will revisit this load once Barry leaves the south.

If you call Berger they will give you loads in the 7RM for the 180 gr. or any other Bullet you want, they may have it in N570.

I have done two Rem 700 Factory guns. One Sendero and one Long Range. One shot best at 70 grains, and the other at 71 grains. I am using Nosler powder and F215s. Great combo. Very lethal load.

jjw
ND

ppoole said:

I have heard people complain loading with N570 but I love using it. Each granule is 1/10 of a grain so getting perfect charges is easy. Just go low and trickle up.

My max load with retumbo before hbn coating was 71.5. (Slight primer swipe). Start low work up like always and be careful.

I will revisit this load once Barry leaves the south.

Click to expand...

Thanks. I'll head over to LRO to see if I can find that thread.
I think I'll start at my original thought of 66gr and work my way up in 0.3gr increments.
Prior to re-barrel, I was using Retumbo and found pressure at 72gr so I'll try to work my way up to there. I'll report back with my findings, good or bad.

I checked my Quick Load it says 72,8 near max and 73 grains over max. My advice would then be start 10 percent les and proceed with cationas you approach max. With my 257Wby it 78gr max and I found 76,6 was max. This was with N570 as well.

I would agree with wild bill. When I asked over at long range only I didn't get much if any input. Quick load is a great tool to help with starting loads. I keep talking myself out of it. I do shoot 175 hybrids but my load with h1000 and retumbo was almost the same. I just have a 1 and 9 and had better stability out of 175.

Do not start with mine like I said hbn requires a higher powder charge due to the bullets being slick.

I did a little bit of testing this morning. I started with 66gr and worked my way up in 0.3gr increments. This powder definitely gives some velocity. I'll post up my chart.
My first indication of pressure was a VERY slight ejector wipe @ 69.5gr. 69.8gr showed no pressure signs but I got primer cratering @ 70.1gr. I never shot anything beyond 70.1gr and I'm calling this MAX.
I did this test only for velocity to find a speed node and to get a feeling where max pressure is, not for accuracy.
I'm trying something a bit different for me, loading by the "speed node". If I'm reading this chart right, I'm going to try load development at 66.9gr, 67.8gr and possibly 68.9gr if the others don't shoot. I will be trying loads 0.2gr below, right on and 0.2gr above these speed nodes. I'll be looking for low SD as well as good accuracy. I get my velocities from a LabRadar so I would think they are true.
I'll post up more results as I get them.

I would look at 68.9 that looks like a pretty good node. You should be able to use seating depth to fine tune the load. Definitely run that charge again to make sure it is a repeatable result.

I got some results today from testing the speed nodes. SD looks really promising on a couple but accuracy was a bit off. On the other hand, accuracy looked good on one with SD being not too bad. Temperature was blistering hot today (for up here) @ 28°C or 83°F
Barrel was allowed to cool between 5 shot strings. I use a battery powered air mattress pump with a hose blowing down the barrel to aid in cooling. Only takes 8-10 minutes and it's right back to ambient temp.
Here are the results at 100m.
Load 1) 66.7gr / Avg. Velocity 2909 / SD 13.3 / ES 37 / Group 1.61"
Load 2) 66.9gr / Avg. Velocity 2920 / SD 12.3 / ES 31 / Group 0.55"
Load 3) 67.1gr / Avg. Velocity 2955 / SD 16.7 / ES 38 / Group 1.92"
Load 4) 67.6gr / Avg. Velocity 2982 / SD 4.5 / ES 12 / Group 1.85"
Load 5) 67.8gr / Avg. Velocity 2994 / SD 0.55 / ES 1 / Group 1.44"
Load 6) 68.0gr / Avg. Velocity 3005 / SD 6.7 / ES 13 / Group 3.09"
Speeds seem to be up some from initial velocity test. I'm thinking it was because of the hot temp today.

I'm going to try the next node at 68.9gr to see how it does. I agree that it does look good on the chart. I'm also going to load up 5 more at 66.9gr and try them out at 600 yards. If it stays under 3/4 moa at that distance, I'll be quite happy and possibly try to play with seating depth a bit. I'm also going to play with seating depth at 67.8gr. Pretty hard for me to turn a blind eye to that SD.

I would definitely give a magnum longer to cool. If you are hunting with it the first shot is the most important. I wouldn't shoot more than 3 before letting it cool. Honestly I never shoot more than 2 until right at the end. Magnums will heat up quick. That's just me unless it's a competitive shooting or apocalypse I don't see shooting a magnum hot. Even if a sounder of pigs come out I have gotten 3 shots on pigs once in my life. To each their own but it can help numbers tremendously. Fired brass brings numbers down as well.

I finished testing the last speed node earlier tonight.

Here are the shooting results;
Load 7) 68.7gr / Avg. Velocity 3028 / SD 12.0 / ES 32 / Group 1.47"
Load 8) 68.9gr / Avg. Velocity 3025 / SD 13.7 / ES 33 / Group 0.95"
Load 9) 69.1gr / Avg. Velocity 3056 / SD 9.7 / ES 23 / Group 0.93"

Tomorrow I'll load up 5 each of 66.9gr and 69.1gr and shoot at 600 yards. For me this is the real test. If they perform well, I'll test a bit more with seating depth to try to tighten up groups. If they don't perform, I'll most likely just scrap using N570 and try again with a different powder.

I am impressed you hit 3000fps so early QL showed that speed at 71 grains. I hope QL is slow on my 257Wby as well.