New handloads for my 375 H&H

[Azklmsr]

Picked up a model 70 Super Express in 375 for a Cape Buff hunt next year and started load development. Working on a load with Superformance powder and 300 gr TSX. Looks very promising. For practice, I picked up some low cost Speer 235 grain spitzers and CFE235. Nice load. Pictures tell the story nicely. Scope was set in the same place for both groups.

Shooting was done off the bench. Interestingly, the 235's have a snappier recoil (significantly higher velocity) than the 300s, which though significantly greater in overall recoil, were more pleasant to shoot even off the bench as the impulse was more of a push than a pop!

Bit more work to do. I'm considering having the chamber opened to 375 Weatherby, primarily because adds a bit of potential of pushing bullets up to 350-400 gr, and because it causes a hornets nest of comments

Side note. Trigger on this particular rifle is the worst in my safe. New trigger spring inbound!

couple of pictures

 

[PHOENIX PHIL]

That’ll work just fine. Mind the copper build up when using the TSX. In my M70 they’re as accurate as yours…..until that copper reaches a threshold. Then it will drop off quickly until I give a good cleaning. Just take a glance at the muzzle every so often. If it looks like a shiny new penny, you’re getting there.

 

[Azklmsr]

That’ll work just fine. Mind the copper build up when using the TSX. In my M70 they’re as accurate as yours…..until that copper reaches a threshold. Then it will drop off quickly until I give a good cleaning. Just take a glance at the muzzle every so often. If it looks like a shiny new penny, you’re getting there.

Great input. Thanks. Interestingly, I did a thorough cleaning prior to going to the range. First few patches were very green. Good scrub and Hoppes got it clean quickly.

 

[Bush Buck]

Top velocity loads from 235 grain Speer or TSX can be unpleasant to shoot but milder loads made with H4895 or IMR4895 can be very nice for practice.
I start with Barnes starting loads for these powders. This is a nice way to get a little more gun handling experience with live fire.
I don't think that CFE233, ball powders in general, or slower powders work well for reducing loads.

 

[Azklmsr]

Great input. Thank you Brush Buck. Buff hunt and plains game hunt coming up and I am considering leaving the 30-06 home and just bringing the 375. It's a very easy weapon to shoot well. In that case, I may work up some 250 TSXX for plains game loads. Probable H4350. The H4895 soft load is a great idea, and I appreciate the suggestion for sure. BTW, thanks for catching the CFE223 vs my typo of CFE235. Don't know where I got that one. lol

 

[PHOENIX PHIL]

Great input. Thank you Brush Buck. Buff hunt and plains game hunt coming up and I am considering leaving the 30-06 home and just bringing the 375. It's a very easy weapon to shoot well. In that case, I may work up some 250 TSXX for plains game loads. Probable H4350. The H4895 soft load is a great idea, and I appreciate the suggestion for sure. BTW, thanks for catching the CFE223 vs my typo of CFE235. Don't know where I got that one. lol

Keep in mind a 300gr bullet in the .375HH is still a 200 yard rifle. I say this as there is something to be said for keeping things simple. Having only one load in the box and also in your ammo belt and eventually your rifle is keeping things simple. It avoids possibly using that lighter bullet when you go up against the buffalo.

 

[Luvthunt]

Keep in mind a 300gr bullet in the .375HH is still a 200 yard rifle. I say this as there is something to be said for keeping things simple. Having only one load in the box and also in your ammo belt and eventually your rifle is keeping things simple. It avoids possibly using that lighter bullet when you go up against the buffalo.

I am with PP

 

[Shootist43]

Azklmsr, yours is a very timely thread for me. Here's why, I was thinking about trying a new load for my 375 H&H(s) using CFE223 and 300 Gr. Nosler Accubonds. I recently purchased a 9.3 X 62 for my son. Bob Nelson 35 Whelen has been trying to get me to try CFE223 in our 35 Whelen(s) for years. I bought an 8 Lb. keg of it several years ago for that purpose. But I got to thinking that it might work just as well in the 9.3 X 62. According to my QuickLoad calculations it should be great for that caliber also. THEN, I got to thinking that it might work for 375 H&H(s) as well. I'm going to my son's for a visit in early May and thought I'd take one of my three 375 H&H(s) to a shooting date that we have planned. Seeing the accuracy of your loads has "pushed me over the edge." My previous handloads using H4350 were accurate but much slower than others I've seen posted here. Thanks for the "nudge."

BTW, if any of you reloaders out there have already given this a go, I'd be interested in seeing your results.

 

[Azklmsr]

Azklmsr, yours is a very timely thread for me. Here's why, I was thinking about trying a new load for my 375 H&H(s) using CFE223 and 300 Gr. Nosler Accubonds. I recently purchased a 9.3 X 62 for my son. Bob Nelson 35 Whelen has been trying to get me to try CFE223 in our 35 Whelen(s) for years. I bought an 8 Lb. keg of it several years ago for that purpose. But I got to thinking that it might work just as well in the 9.3 X 62. According to my QuickLoad calculations it should be great for that caliber also. THEN, I got to thinking that it might work for 375 H&H(s) as well. I'm going to my son's for a visit in early May and thought I'd take one of my three 375 H&H(s) to a shooting date that we have planned. Seeing the accuracy of your loads has "pushed me over the edge." My previous handloads using H4350 were accurate but much slower than others I've seen posted here. Thanks for the "nudge."

BTW, if any of you reloaders out there have already given this a go, I'd be interested in seeing your results.

Look forward to seeing your results. I'm back at the range next week doing some chrono work with the loads shown and a 250 gr load with H4350. I would be very interested to see how your CFE223 works with a 300 gr bullet. The Superformance I'm using is giving me well over 2500 FPS and I'm expecting to finish right at about 2600 fps. Will advise when I do my next session.

 

[wswolf]

Azklmsr,
Quoting something I posted five years ago:
"I had a Model 70 rechambered (to .375 Ackley) because I was intrigued by the high velocity listed in Ackley's Handbook for Shooters and Reloaders. Namely 300 grain bullets at 2740 fps. I reduced Ackley's load by 5% and blew a primer right out of the case. I later learned that Ackley's data routinely produced extremely high pressures and should be avoided.

After more careful experimentation I found that velocity could be increased somewhat, but not a great deal, over the .375 H&H. The potential velocity increases by 1/4% for each 1% increase in case capacity (see The Rules by John Barsness). Recoil became vicious.

Feed reliability from the magazine was not dependable if more than one cartridge was loaded. Extensive work on the magazine and feed rails would be required. I sold it to a fellow who had formerly worked as a gunsmith and thought he could get it to function. Don't know how it turned out.

I did not regard this as a feasible conversion and would avoid it like the plague".

After measuring the volume of Winchester cased I calculated that, at the same pressure, velocity could be increased by 3.1%.

Since the .375 Weatherby is similar in volume and the case has a similar taper I would expect similar results to the .375 Ackley. I strongly suggest Finding out if .375 Weatherby cartridges feed from the magazine reliably before proceeding.