VV N570 vs RL33 velocities

[rooster721]

Guys,

Curious whether any of you have taken the time to test these powders side by side and chrony'd the differences?

...could have been in 338's, 300's, 7mm's, doesn't much matter. I'm just curious whether anyone can say if 570 might be a closer match to R33 for velocities than what Retumbo typically is, for example.

Am in the process of trying to get my hands on some 195's for my Firebird, and seriously considering N570 as a powder instead of Retumbo.. this is why I bring the question up*

Would I be way outta left field thinking such a heavy for caliber bullet like the 195 might allow a powder like N570 to perform to its peak in a situation like this?? I know I read the 338 Terminators prefer the 570 over 33. Wonder if 570 would outperform 33 in the case of the 195 and a high capacity 7mm casing(?)

 

[BEEMAN]

I tried both R33 and 570 in my 6.5 Sherman. The N570 produced higher velocities for me. I could not get enough R33 into the case to reach max velocity. With 64 gr of N570 and a 140 Berger I am at 3329 fps. I also use N570 in a 22-284 shooting 80 gr Bergers. Velocity and ES seem good with N570. To bad it is so hard to find.

 

[JeffVN]

I run them both in my 338 LM Improved. They both drive a 300 gr. Lapua Scenar to 3,000 fps (they both actually hit 3,100 fps but the pressure was too high to survive the summer heat in the desert.

I will say this, it takes considerably more RL-33 (105.5 gr.) to match the velocities of VV570 (100.5 gr.), but they will drive the 300 gr. Scenars to the same velocity node.


JeffVN

 

[rooster721]

Appreciate the replies.. actually am surprised there's such a difference in the amount needed (Jeff) 5 grains is alot! The way it's sounding, N570 might do very good behind a 195. Glad I grabbed a few pounds while I could.

Have you guys seen pretty drastic swings in velocity with either powder winter vs summer?

With Retumbo, my load in the 338 sits at 2775 +/- the freezing mark, 2800 mid-summer (80F kinda thing) and 2750-ish absolutely dead cold -25F... wonder if 570 is very different than that, or even less effected??

 

[orch]

I tried both R33 and 570 in my 6.5 Sherman. The N570 produced higher velocities for me. I could not get enough R33 into the case to reach max velocity. With 64 gr of N570 and a 140 Berger I am at 3329 fps. I also use N570 in a 22-284 shooting 80 gr Bergers. Velocity and ES seem good with N570. To bad it is so hard to find.

Hey there, sorry to hijack the thread..... Hey beeman who built your 6.5 Sherman? I've got a 6.5 barrel laying around that I'm trying to decide what to do with.... I'm in MB too, actually think we have met a couple times at Miami buck night and drinking with the Alexander boys a couple times...

Orch

 

[BEEMAN]

Hi. Yeah that's me. I had my Sherman built by Jim Borden actually. There's a local guy that did my 300 WM last year and he does good work. The fit and finish on Bordens work is unreal. Just not a good time for us to have one built in the U.S. with our low dollar.