375 H&H Accuracy

[Bruce]

DAMN fine shooting, Boela!!!

 

[Boela]

Shootist, I would rather err on the cautious side and start working from a min recommended load upwards until you find your rifles sweet spot with the combination of variables that you will be using. Personally, I will look at reloading info, and keep it on the paper.
No two rifles will shoot the same grouping using the same reloaded ammo- as you know. TBL also plays a role, and will it be necessary that you determine that too using your own rifle.

I am absolutely a beginner when it comes to reloading and it could just as well have been a fluke getting those tight groups with my rifle. I simply managed to hit the sweet spot using the Peregrine bullets. The same load using Hornady 300gr DGS bullets does not give me nearly as a accurate grouping as this.

I unfortunately do not own a chrony, so I have no idea what velocities the bullets are running at. I know that it is one of the big no-no's when it comes to reloading.
I used 68gr of S335.

Regarding the age of my Mod70- I baught it second hand from a gun dealer and were I unable to obtain any historical info regarding it. It was still in a almost as new condition when I bought it in 2009 though.

 

[Shootist43]

Boela, have you tried this load for the second or third time to see if the original was a fluke? Or stated another way to see if the grouping is repeatable?

 

[Boela]

I have indeed taken the same batch that I reloaded back to the range a fortnight later and got almost duplicated accuracy from them.
I plan on doing a couple of hunts first before revisiting the load / bullet combo.
I am a bit reserved using the Peregrine bullets due to amount of damage and bruising I saw on a Reedbuck that was shot with a 180gr bullet.
Bottom line is that it seems that my rifle really likes this combination though.

 

[wesheltonj]

. . . Regarding the age of my Mod70- I baught it second hand from a gun dealer and were I unable to obtain any historical info regarding it. It was still in a almost as new condition when I bought it in 2009 though.

There is an on-line S/N look up, that will give you the date of manufacturer.

 

[Shooter375]

 

[Ridgewalker]

View attachment 276528

Nice group, but...
That is 3 grains more than the Lyman 49th manual 67.0 maximum and 2.5 grains more than the Swift 2nd 67.5 manual. Do you get any cratering or hard extraction in hot weather?

 

[PHOENIX PHIL]

Nice group, but...
That is 3 grains more than the Lyman 49th manual 67.0 maximum and 2.5 grains more than the Swift 2nd 67.5 manual. Do you get any cratering or hard extraction in hot weather?

I would preface this of course with the obligatory "start well below book maximum and work up slowly" when developing your own loads.

But that said, this is not surprising to me. My best load using IMR4350 with the 300gr A-Frames is about 3gr above max. Yah, I was a bit nervous too, but my velocity is about the same as listed here, 2550fps IIRC. And that falls in line with lots of those who load for this caliber.

 

[Shooter375]

Nice group, but...
That is 3 grains more than the Lyman 49th manual 67.0 maximum and 2.5 grains more than the Swift 2nd 67.5 manual. Do you get any cratering or hard extraction in hot weather?

Ridgewalker, I was a bit concerned because this load exceeds some load book maximum load data but I have not seen any signs of pressure yet. There is a bit of a mystery surrounding RL-15 maximum loads. For example the Barnes load book lists the maximum load for a 300gr bullet at 75 grains of RL-15. Also, many forums list pet loads at 70-71 grains of RL-15. Has any one else had any experience they wish to share?

 

[Newboomer]

My Win 70 Safari Express likes Barnes 235 TSX and 350 TSX. I load both with 4064. 63 g for the 235s and 58.2 g for the 350s. I took it out last weekend and shot 1.5 to 2 inches at 100 yards off sticks with both rounds. These are sort of midrange loads in the book but they work well enough for one shot kills out to 200 yards.

 

[Ridgewalker]

Because of the “bands” on Barnes, Peregrine, NorthFork and others, they can usually handle more powder but have less pressure. The bands seem to reduce the friction.

My concern aside, as Phoenix Phil said, some rifles can handle it and some cannot. Example my MRC started getting cratered primers using the max Barnes load on my 300 TSX in 90 degree weather. I backed off a couple of grains and chronographed it. 2,655 FPS! 1/2” groups, but I am planning to reduce the load to equal Barnes factory loading of 2,529 FPS. Hopefully the good grouping will remain.

 

[PHOENIX PHIL]

Because of the “bands” on Barnes, Peregrine, NorthFork and others, they can usually handle more powder but have less pressure. The bands seem to reduce the friction.

My concern aside, as Phoenix Phil said, some rifles can handle it and some cannot. Example my MRC started getting cratered primers using the max Barnes load on my 300 TSX in 90 degree weather. I backed off a couple of grains and chronographed it. 2,655 FPS! 1/2” groups, but I am planning to reduce the load to equal Barnes factory loading of 2,529 FPS. Hopefully the good grouping will remain.

You got 2655fps AFTER backing off a couple of grains?! That was a hot load for sure.

 

[AMont]

I get half inch groups with 72g RL15 /270g Barnes TSX going 2600+ FPS out of a CZ 550 American. The best it did with IMR 4350 was 1.25 inch.

 

[JMJ888]

I just had a left handed M70 built off of a Post 64 Classic 7 Rem Mag I had laying around. Put a Brux #5 contour on it finished at 24". Initially just put it in a factory Safari Express stock...my gunsmith sent me a picture of the first group out of the gun with factory Barnes ammo with 300gr TSX's. He said chrono average was 2525fps and guessing group is in the 3/4"-1" range.

When I received the rifle I immediately sent it off to be restocked on a blank I had been saving for the project. I have a 15.25" LOP and the factory stock with spacers was just too ugly to look at. Should have it back in about 2-3 weeks when it gets back from bluing. In the meantime I get to stare at the finished stock my builder sent me pics of.

 

[Michael Dean]

I've got an old Colt Sauer that I'd never trade or sell; shoots sub MOA all day long. Used it 12-14 years ago to kill an Elk at 500 yards out in Montana. I still remember it shooting a 270 grain bearclaw that I reloaded. The rifle is well balanced and is about eight and a half pounds with its scope. Not an ultralight but light enough to carry all day.

 

[Don458]

Hi, I have a CZ 550 Mag in 375 H&H and with most bullets(Nosler, Speer, Barnes ) it shoot around 3/4 inch 3 shot groups at 100 yards. The actual bullet weight doesn't seem to matter much in accuracy from 200 grain through 300 grain. Using the Speer 235 grain bullets I can get real close to 1/2 inch 5 shot groups at 100 yards. I have only shot a Zebra with it using the 235 Speer bullet and was pleased with the results. It was a complete pass through at about 150 yards, it ran 50 yards and dropped. I reload all my own ammo and I don't use and factory ammo. I bought this rifle used at a very low price because the bore was badly copper fouled. It took 2 days to clean up. Just pick a load from the reloading manuals available. My rifle it not fussy at all, perhaps I am just lucky.

Not to highjack the question, but out of curiosity what did you do to clean up the copper fouling? It is a real pain sometimes to clean up. I am always asking people how or what they do and use for it. Thank you

 

[PHOENIX PHIL]

Not to highjack the question, but out of curiosity what did you do to clean up the copper fouling? It is a real pain sometimes to clean up. I am always asking people how or what they do and use for it. Thank you

You didn’t ask me but this is what I use. No ammonia and it works quick:

https://www.boretech.com/products/eliminator-bore-cleaner

 

[PARA45]

I shoot a lot of Weatherby calibers, and I also use Boretech Eliminator, and its outstanding stuff. You'll never use another solvent to clean your bore.

 

[Sycamore59]

I’m dialing in my 375 HH Ruger No. 1. Put a 5 shot, 1” group together earlier this week using 68.3 grns of Varget behind 250 grn Barnes TTSX. Did not have the chronograph set up, but will have it set here the next time I shoot.

 

[Rick Cox]

Here is a somewhat typical target from my CZ550. Haven't tried much else... for what it is worth, my scope is a Leupold VX 5 1-5.