.375 H&H 300g bullets best velocity

[benchracer]

I have some RL19, so I could do a quick velocity run up to see what it does the next time I am able to experiment. I really think I am getting to the point where Quickload would be very useful. I am planning to add that tool to my arsenal and see what it spits out. I am also contemplating a Magnetospeed chrono to make things easier.

I am glad to encounter another interested .375 shooter. There can't be enough of us to my way of thinking. I apologize in advance for the slow pace of my experiments. I only have a small window of opportunity to continue them every few months.

I will continue to post results as development continues. When I have something meaningful (like a finalized load), I will post photos.

 

[benchracer]

One more link that may be of interest:

http://www.longrangehunting.com/forums/f17/375-weatherby-dialed-121054/

I really liked this guy's setup and he was getting some pretty impressive results.

 

[Kennibear]

I see in his post he is using H414, the same powder as WW760. I have a developing load of 260gr AB, 79.5gr WW760, Fed #215, that clocks 3000fps+ with a SD of 9fps. This powder holds potential. The above load is maximum pressure in 375 Ruger and is shot through a 26" barrel.

Read about the Magneto-Speed on another site. One caveat: hanging things on the barrel changes the accuracy. Optical chronographs allow group testing concurrent with velocity. The Magneto seems like it would be faster to set up and insensitive to environmental conditions, a real plus when things seem haywire. Pick and choose. I wonder if CFE causes problems w/ the Magneto-Speed as it supposedly may contain Tin?

Have you tried the Speer 270gr SpBT? I bought a box but have to figure out a load as Speer does not list any 375 Ruger data.

Keep going!!!

KB

 

[benchracer]

What kind of accuracy are you getting with the WW760? I was pretty impressed by the accuracy exhibited by the .375 WBY w/H414.

I normally test velocity and accuracy separately, so the Magnetospeed hanging on the barrel doesn't present a problem for me. Portability and versatility are the selling points for me. Don't know whether CFE would cause an issue or not. I was trying that with 250g TTSX's in my H&H, but never finished development. It would be interesting to see if an issue arises with that or not.

I haven't tried the Speer bullet. I have some Hornady 270g SP flat base bullets that I will probably never shoot. Alliant shows data with the Speer BTSP in H&H. It should get you in the ballpark for a starting load:

Alliant Powder - Reloader's Guide

Hodgdon shows .375 Ruger data for the above mentioned Hornady bullet. Again, not exact, but should get you in the ballpark:

Cartridge Loads - Hodgdon Reloading Data Center - data.hodgdon.com

 

[Kennibear]

Just starting with this rifle. Like you I do not test groups until I have the velocity I want. As this was the first 29rnds fired getting on target was @ 25yds. Most shots not even counted until the chronograph was dialed in. But that load was the last one fired and it was a 3/8" hole for 5 rnds. I should mention that I have chronographed since the 80's. Never found a load w/SD > 30fps thar made little holes. Every load <20fps drilled single holes @ 100yds. This one went SD=9fps so it gets 100yd check. Zero spread at 25yds.

My phone stores PDF files so I keep Ramshot, Accurate complete load manuals on it. Selected pages of VihtVouri, Hodgdon's and Alliant also. Helps when you look @ powder they have and can see if it works. I did that when I passed up AA 270 @ $20/lb not knowing it was ideal for 375 Ruger. You may want to look at it too. Never get caught without data again!!!

KB

 

[Kennibear]

My typing sucks! AA 2700. Ramshot Hunter is on the list when I can find some. Anything around 4350 speed and dense.

KB

 

[Lefty7mmstw]

try 4320 guys. Extruded but short grain and fine enough to measure well. I'm using the heck out of it in my 375h@h. Just a bit faster than 4350 but slower than 4064/4895.

 

[Kennibear]

Lefty

Thought about that. Problem: only can I have is 30 years old. I haven't seen 4320 on the shelves in about four years. Delivers top velocity and accuracy in 150-30/06. If I can find new stock I will try some. Same speed range as 760/414, Biggame, and RL15.

KB

 

[65WSM]

H4350 and IMR 4350 are single base powders and very old technology. The Reloader 17 is a new formula and is significantly faster with similar pressure. The VithaVuori N-540 produced 2800 fps easily with 260 gr Accubonds on the bench next to me at the range yesterday (375 Ackley 26 inch barrel).

VV N-550 has the same burn rate as 4350 but significantly more zoom. If speed is your game, VV 500 series is the fastest you are going to get.

 

[Kennibear]

65WSM

Ditto to what you posted except burning rate. H4350/ IMR 4350. RL17 and VV 540/550 have about the same burn rate. VV540/550 and RL 17 are both double based as compared to single based powder. Their rates are adjusted to approximate 4350 but their energy density is higher owing to the added nitroglycerin content. Like you I have found they have more energy to develop velocity than 4350. They burn hotter too so it has an effect on barrel life. Probably not enough to concern 375 H&H shooters.

Reloader is denser physically also. Ball powder even more so. In a 375 Ruger case filled to the shoulder/ neck junction (same case for all three):
Superformance (ball)= 95.6 grains
Reloader 19 (double based stick)= 89.6 grains
IMR 4831 (single based stick)= 84.6

You can use this to your advantage by utilizing the extra powder density to shift your burning rate choice to the slower end. By switching to ball powder you can really move slower. Superformance, BigGame, WW760 and AA2700 that I have used in the 375 Ruger so far are no where near 100% loaded density. I am looking at WW780 and slower ball types to fill the case and still reach top pressures.

That has worked for me to develop maximum velocity in the past. Doesn't guarantee accuracy though.

KB

 

[benchracer]

I stumbled across this .375 H&H load data. Food for thought:

Real Guns - Handload Data - .375 H&H Magnum

 

[Kennibear]

Real Guns online magazine is one of my primary research places for loads. His work on the 375 Ruger was a deciding factor in buying one.
There are different bullets than the regular makers used, like the GSC's Len advertises on this site. He also uses a wide range of burning rate powders. He loaded RL19 behind the Sierra 300gr SpBT in 375 Ruger to good effect. Be advised that some of the loads can be pretty hot.
Always a good plan to collect as much data as one can before sitting down to the loading bench.

KB

 

[benchracer]

Here is some load data that I received from Cutting Edge bullets while discussing how to tune the MTH's:

View attachment 375 H&H, 300 MTH and 325 LAZER, for single shot or single feed ONLY, 11-26-13.pdf

I thought this might be interesting given our discussions about appropriate powders and burn rates. Note that data is included for the soon to be released 325 grain Lazers.

 

[HarryN]

Thank you for posting the info here. I am considering to pick up a 375 H&H or similar, and it is always helpful to have the path partly blazed before you jump in.

I had actually been looking at moderate recoil / 2000 FPS / using CEB 235 grain Raptor ER round for my use, but after looking at the BC of those MTH rounds - wow.

There are just so many decent performance rounds at reasonable prices for this caliber, it is hard to not consider it.