I have imr 4350, 4064 and reloaded 15 on hand. Anything here suitable for a 160 np in 7x57?
48gn of 4350 will get around 2640fps in a 22" barrel using 160gn Accubond.
46gn Rel 15 will get 2740fps using the 160gn Failsafe.
46gn Rel 15 got me 2756fps using the Partition
All safe and accurate max in my rifles so work up please.
H4350. Add powder until an accurate chronograph reads 2700fps, unless you come across an accuracy node prior.
You're set, i use an old book load of 49gr imr-4350 under 175gr grand slams and partitions for 2700 fps in my 24in barreled 7x57, bughole accuracy to boot, i use RP brass and CCI-250 primers.
to me, RL 15 or 4064 is NEVER a bad choice in almost ANY caliber...
and yeah, I've carried either load afield with the 160 Nosler or Speer....and they worked great...
both in my Ruger and my Featherweight....
The rifle goes Boom... the game went FLOP....
I went thru this back in January for a LH 7x57 Mauser with Lyman peep sight. Settled on 42gr of IMR 4350 with 160gr NPT's seated at 3.100" for my rifle. Not setting any speed records. But, accurate and comfortable for me to knock around.
7x57 160 NPT Powder Selection...
I have never loaded any bullets heavier than a 154gr Hornady Interlock in my Winchester Featherweight, but when I loaded those I tested both Hodgdon and IMR 4350. Both powders provided 3/4'' to 1'' groups. Id say your IMR 4350 would be a more than suitable choice with the 160 Nos Partition.
I'd prefer the slower 4350 with a 160n bullet. I got good accuracy and velocity with H4350 (not IMR) in my 7x57 with the 160gn Sierra.
Of the 3 you mentioned, definitely 4350 for 160's (although I use H4831).
IME, RE15 is the berries for 120's.
Not what you have on hand, but I get excellent accuracy with RL19 in the 7x57 and either 160 or 150 Partitions. If I recall correctly, 47.5 grains of RL19 for the 160 at a moderate velocity, and 50.5 grains with the 150 at a chronographed 2880 fps with the 150. Both in Ruger No.1s, the 160 in an RSI and the 150 in a Krieger 24" barrel 1A. Haven't tried either in the other rifle yet. Both were sub MOA, and the RSI was closer to 1/2" groups with the 160. Best load I've ever used in that rifle for sure. If you can find some RL19, it's worth a try.
I settled on H4350 with 160's in my 7x57 rifles. But IMR would do as well.
I would try RL26, and Norma MRP. I have used both in my 7mm-08. The RL26 is the best of the two. RL23 might be worth a try if you can get
enough in the case? You can not in the 7mm-08.
I would also go wiih IMR4350, but have pointed out many times before now that maximum charges in the 7x57 depend a LOT on throat length, which can vary considerably. As a result maximum loads can vary 2-3 grains, depending both on the throat and bullet.
With 160's I tend to load to 2650-2700 fps, depending on barrel length rather than exact powder charge.
Speaking of 7x57 throat variations, does anyone know the SAAMI and CIP specs for it? I've looked at the SAAMI specs but can't make heads or tails of it. It'd be nice to know if I ever (when) have a barrel replaced.
Thanks
RM