I have question. Should 2700fps be hard to reach with 260 nosler part.or accubonds? I get great acc. with 77gr of imr4350 3/4". They start to spread above that. 78gr yeilds 2650+. Any sugge4stions on a diff. powderRL15? or ? 78gr is also flattening primers. Thanks

load data from Nosler 260 grain bullets:


260 Nosler IMR IMR-4064 70.0 2,721
Remarks: maximum load
260 Nosler IMR IMR-4064 68.0 2,617
260 Nosler IMR IMR-4064 66.0 2,512
Remarks: most accurate load tested
260 Nosler Alliant RL-15 73.0 2,793
Remarks: maximum load; most accurate powder tested
260 Nosler Alliant RL-15 71.0 2,721
Remarks: most accurate powder tested
260 Nosler Alliant RL-15 69.0 2,648
Remarks: most accurate load tested; most accurate powder tested
260 Nosler IMR IMR-4350 78.5 2,707
Remarks: maximum load
260 Nosler IMR IMR-4350 76.5 2,639
260 Nosler IMR IMR-4350 74.5 2,570
Remarks: most accurate load tested
260 Nosler Winchester W-760 78.5 2,747
Remarks: maximum load
260 Nosler Winchester W-760 76.5 2,690
260 Nosler Winchester W-760 74.5 2,633
Remarks: most accurate load tested
260 Nosler Vihtavuori VV-N160 81.0 2,681
Remarks: maximum load; most accurate load tested
260 Nosler Vihtavuori VV-N160 79.0 2,621
260 Nosler Vihtavuori VV-N160 77.0 2,561
260 Nosler Alliant RL-19 80.0 2,604
Remarks: maximum load; most accurate load tested
260 Nosler Alliant RL-19 78.0 2,537
260 Nosler Alliant RL-19 76.0 2,470
260 Nosler IMR IMR-4831 80.5 2,734
Remarks: maximum load
260 Nosler IMR IMR-4831 78.5 2,669
260 Nosler IMR IMR-4831 76.5 2,605
Remarks: most accurate load tested

I get 2680 fps at 10 feet in front of the muzzle (JBL says that is 2689 fps at the muzzle) using 76 grains of IMR4350.

Win M70-375 H&H: 260 grn Partition with 76 grns IMR4350 - OAL 3.582 at 2680 fps - Group 0.4"

Win M70-375 H&H: 300 TSX with 67.5 grns of IMR4064 - OAL 3.620 at 2480 fps - Group 0.5"

Oops, I reversed the two numbers in the partition load.

I find it interesting that with a 260 grain bullet the IMR 4064 is getting warm at 70 grains. i commonly use 67 and 68 with 300 grain bullets without any issues?

308 sako It was 78.gr of imr 4350 that was getting warm.

fjold Is that 67 gr or 77?

Boatammo,

What's the problem? You are getting 3/4" groups with 260's at 2650. Exactly why are you looking for 2700?

Relax and practice with a load that is working for you. At the end of the day, you'll be happier with the result. Kudude

Kudude Not getting that at 2650. Going up to 2650 really opened the groups. I'd be thrilled with 3/4 @ 2650.

I have had very good results in my pre-64 M 70 with:

Case: WW
Primer: WLR
Load and Powder: 85 gr (12" drop tube) IMR or AA 4350
Bullet: 260 gr NP
Velocity: @ 2800 fps without any pressure sign and good accuracy : @ 1 to 1,5 "/100 meters

My experience

Good luck and best regards

PH

quote:

Originally posted by boatammo:
I have question. Should 2700fps be hard to reach with 260 nosler part.or accubonds? I get great acc. with 77gr of imr4350 3/4". They start to spread above that. 78gr yeilds 2650+. Any sugge4stions on a diff. powderRL15? or ? 78gr is also flattening primers. Thanks

It should be possible for you to attain 2700 FPS with a 260-grain bullet, but that does not mean that your best accuracy will be at that level. Best accuracy might be at, above, or below that velocity. Obviously, when you use IMR 4350, your best accuracy is BELOW the 2700-FPS level......

I have had better acuracy results in my .375 H&H's with IMR 4064 than with IMR 4350 or WW760, but each rifle is diffferent.

I have had better luck with RL-15 with the lighter bullets in the .375HH. I think it would be worth your while to try, after all what fun is handloading without trying new stuff.

Try IMR 4320, start about 65 and go up carefully. I run 67 grains behind 300gr Noslers, no problem vel about 2550, also run Barnes originals. Not many folks seem to use 4320, but it shoots good in my Mod 70 Classic.

Not a problem to get 2700 ft/sec in a 260 gr. bullet. See my post under favorites.
https://forums.accuratereloading.com/eve/forums/a/tpc/f/4911043/m/645107953

boatammo,
I have used both, R15 and, as I said IMR-AA 4350. I worked up loads with the components I described in my other post.
With 75 gr of R 15: @ 2700 and no expantion of case head.
With 85 gr 4350: @ 2800 no expantion of case head.
Accuracy 1- 1,5 " 100 meters.
Really I was surprised by the 4350 load. Very good, very lightly compressed. I like little compression in loads.
Good luck
PH

thanks guys I'm getting there now with rl 15 and 4350. Partitions seem to be shooting quite a bit better than accubonds