.375 H&H and IMR 4350

[Underdog75]

Anyone have experience with this powder in the 270 grain class bullet?

I am going to be working up both Hornady and Barnes TSX 270gr bullets and have a bunch of IMR 4350.

 

[BRICKBURN]

Close only counts in horse shoes, so I can't help.
I use 250TTSX and H4895
Hope someone can help you out.

 

[Rob404]

Can't help with 270g
best accuracy loads I got were
75g of Win760 with a 300g Sierra getting 2583FPS

 

[Pheroze]

I used H 4350 first for Hornady for practice then loaded up 270 grain Woodleigh with H4350 for my safari. Awesome. I think the 270 is a great weight for that rifle. My recollection was 2650 fps but would have to check. I think it is very close to IMR4350.

 

[greyfox]

Yes, I use IMR 4350 almost exclusively.300 Nosler, 75 grains IMR 4350 and magnum primers.

 

[PHOENIX PHIL]

I haven't used IMR4350 with 270gr bullets, but I have with the 300gr version and it works great. It would seem strange to say it, but it may be a bit too slow for the 270gr projectiles. As Brickburn does, I used H4895 with 250gr bullets. Varget may be a better choice as it's between those two burn rates.

 

[Ray B]

I've used the Hornady 270 grain with 75 grains of IMR 4350 with good results at the range, among other bullets and powders. I like the powder, along with H4350 but for hunting I used BBCs or Noslers.

 

[greyfox]

Ray, that's what I wasn't going to say: I use 75 gr IMR 4350 for both 300 (max load) and 270/260 (medium load but very accurate) Seems strange using the same weight with different weight bullets.

 

[Underdog75]

Very useful information guys. I have some varget too that I am probably going to try.

 

[Ray B]

I haven't tried Varget, but I understand it is similar to IMR 4064, which was one of Jack O'Connor's listed loads for lighter bullets in the 375H&H. I've used it but seems that I got better performance from 4350.

 

[Brandon.Gleason]

I'm not sure about the 270's, but with woodleigh 350's I've gotten some amazingly wonderful groups with IMR4350. Geoff from Woodleigh had suggested H4350 to me for that weight bullet, but said the IMR4350 would interchange just fine as their quoted H4350 loads were rather conservative on pressure.

With 270gr TSX's, I've achieved great accuracy with RL15, seating the bullets a tad long in my CZ.

 

[Tom Leoni]

You can't be the "Underdog" if you are using and reloading for the king of calibers...

Ken Waters lists a 78-gr 4350 load for the Remington 270-gr S. P. with the comments "case expansion near max; very accurate." He chronographs it at 2,640 f/s out of his 24"-barrel Browning Medallion (reference: p. 439 of Pet Loads). He also lists a 79-gr load for the 270-gr Nosler Partition, which yields 24 f/s more; "case expansion near max" but no notes about its accuracy.

I hope it helps. On a somewhat unrelated note, my favorite (so far) 270-gr load is 68 grains of RL 15 for about 2500 f/s, just shy of the 72-gr RL 15 load that would duplicate the original 61-gr cordite number. My reason for scaling down a bit is that mine is the flanged version. With the Speer 270-gr boat-tail spitzer it's MOA accurate, though, and not unpleasant to shoot off the bench, although my rifle weighing a touch over 10lbs fully dressed surely helps.

My next experiment is with Winchester 760. 76 grains should also give me around 2500 f/s and I have never heard a negative comment about that powder's potential for accuracy in the .375.

 

[Rob404]

I had great results with Win 760

 

[Tom Leoni]

I had great results with Win 760

Not surprised at all. Never heard a less than stellar report about it when used in the .375.

 

[Rob404]

300gr Sierras at 200yds with my Whitworth using Win 760

 

[Shootist43]

Rob404, how many gr. of Win 760 did you use? What was the velocity. How many shots are in the group? Why the flier?
I haven't reloaded for my 375 H & H yet, and I have both 4350 and 760 powders available.

 

[Rob404]

75gr with a muzzle velocity of 2583fps as to the how many in the group I think maybe 6-7 as to the flier if you count the amount of patches along with the holes probably around 20 rds so I'm thinking a pre recoil flinch it's been a while since I sighted in the 375. Now that I have the 404jeff I'm thinking about dialing it back to shoot 250s

 

[Ray B]

I'm thinking about dialing it back to shoot 250s

In both the 375 H&H & the RUM my favored weight is 250. If for "softer" game I use the sierra SBT and for more difficult game I can use the Swift A-Frame, or if I get REALLY serious, it's the BBCs.

 

[Tom Leoni]

Rob, that's some fantastic shooting. BTW, I once almost bought a Withworth Express, and your grouping makes me regret the "almost" part. Here's my .375 H&H Flanged with RL-15 and a 270-gr Speer BTSP. Again, dying to try the Win 760.

 

[Rob404]

Whitworths don't get a lot of respect but the actions are rock solid and even though there reputed to have soft barrels I haven't been able to bend mine as hard as I try