Developing an unpublished load

[Hunter max-4]

I hunt in a restricted rifle zone for whitetail hunting. 35 cal or larger straight walled cartridge with a max case length of 1.80”. I have a 375 Winchester big bore 94 that is an really fun gun to shoot and would love to use it for whitetail hunting. The case length is just over 2” so I would need to trim .2” off the case.
I am wondering how I go about figuring out a good starting load for this based off the factory load data for a full case length? I have 3 or 4 different powders that are recommended for full length cases as well as a few different bullets.


I know there are other rifles that fit these restrictions and I own some of these but I’ve always liked to be a little different.


Any help trying to make this a legal cartridge to hunt w in my area?

 

[Bc'z]

How much bullet is in a full cartridge case versus how much in a trimmed case if loaded to same length?
I'm thinking you might be able to start at minimum load and work up provide you have proper/enough grip on the shank

 

[Hunter max-4]

How much bullet is in a full cartridge case versus how much in a trimmed case if loaded to same length?
I'm thinking you might be able to start at minimum load and work up provide you have proper/enough grip on the shank

That is a good question that I do not know the answer to yet. Bullets are .831” long

 

[Jager]

That might be the most curious hunting regulation I've ever heard of.

But to your little wildcat experiment... modeling a conventional 375Win load in QuickLoad with a Hornady 220gr FP and 30.3 gr. of IMR-3031, with standard case length of 2.020" and a COAL of 2.500," shows 1665 fps / 20,226 psi out of a 20" barrel. Seating depth of the bullet, according to the QL database, is 0.349." Case volume in H2O is assumed to be 48gr.

Trimming the case back to 1.8" and reducing the COAL a comparable 0.220 (overall COAL of 2.280" and bullet seating depth remains unchanged at 0.349") gives 1734 fps / 24,286 psi IF - big if - the resulting reduction in case capacity is 44gr. If the resulting case capacity is 40gr. you'd see 1820 fps / 31,195 psi. ( I don't shoot 375Win and so I'm just guessing at those case capacity reductions... you'd have to measure a couple cut-back cases to be sure).

HOWEVER, your challenges are not over... QL shows your 1.8" cut-back case to now have a loading density of 116%. That's a significantly compressed charge. You might find other powders which work, at lower load densities.

There's no doubt you could make all this work. But you'd have to be more specific with the bullet, powder, and case combination that you're targeting.

That said, my last caution would be about the potential effects of shooting your shortened wildcat in your Big Bore rifle. Like firing hot .38 Special rounds in a .357 Magnum revolver, or .22 Short rifle rounds in a .22 Long Rifle chamber... you may experience sufficient chamber erosion just in front of the shortened cartridge to make chambering standard 375Win cartridges a problem.

Good luck!

 

[457ciSBC]

That might be the most curious hunting regulation I've ever heard of.

But to your little wildcat experiment... modeling a conventional 375Win load in QuickLoad with a Hornady 220gr FP and 30.3 gr. of IMR-3031, with standard case length of 2.020" and a COAL of 2.500," shows 1665 fps / 20,226 psi out of a 20" barrel. Seating depth of the bullet, according to the QL database, is 0.349." Case volume in H2O is assumed to be 48gr.

Trimming the case back to 1.8" and reducing the COAL a comparable 0.220 (overall COAL of 2.280" and bullet seating depth remains unchanged at 0.349") gives 1734 fps / 24,286 psi IF - big if - the resulting reduction in case capacity is 44gr. If the resulting case capacity is 40gr. you'd see 1820 fps / 31,195 psi. ( I don't shoot 375Win and so I'm just guessing at those case capacity reductions... you'd have to measure a couple cut-back cases to be sure).

HOWEVER, your challenges are not over... QL shows your 1.8" cut-back case to now have a loading density of 116%. That's a significantly compressed charge. You might find other powders which work, at lower load densities.

There's no doubt you could make all this work. But you'd have to be more specific with the bullet, powder, and case combination that you're targeting.

That said, my last caution would be about the potential effects of shooting your shortened wildcat in your Big Bore rifle. Like firing hot .38 Special rounds in a .357 Magnum revolver, or .22 Short rifle rounds in a .22 Long Rifle chamber... you may experience sufficient chamber erosion just in front of the shortened cartridge to make chambering standard 375Win cartridges a problem.

Good luck!

Hence the release of the 350 Legend

 

[Hunter max-4]

That might be the most curious hunting regulation I've ever heard of.

But to your little wildcat experiment... modeling a conventional 375Win load in QuickLoad with a Hornady 220gr FP and 30.3 gr. of IMR-3031, with standard case length of 2.020" and a COAL of 2.500," shows 1665 fps / 20,226 psi out of a 20" barrel. Seating depth of the bullet, according to the QL database, is 0.349." Case volume in H2O is assumed to be 48gr.

Trimming the case back to 1.8" and reducing the COAL a comparable 0.220 (overall COAL of 2.280" and bullet seating depth remains unchanged at 0.349") gives 1734 fps / 24,286 psi IF - big if - the resulting reduction in case capacity is 44gr. If the resulting case capacity is 40gr. you'd see 1820 fps / 31,195 psi. ( I don't shoot 375Win and so I'm just guessing at those case capacity reductions... you'd have to measure a couple cut-back cases to be sure).

HOWEVER, your challenges are not over... QL shows your 1.8" cut-back case to now have a loading density of 116%. That's a significantly compressed charge. You might find other powders which work, at lower load densities.

There's no doubt you could make all this work. But you'd have to be more specific with the bullet, powder, and case combination that you're targeting.

That said, my last caution would be about the potential effects of shooting your shortened wildcat in your Big Bore rifle. Like firing hot .38 Special rounds in a .357 Magnum revolver, or .22 Short rifle rounds in a .22 Long Rifle chamber... you may experience sufficient chamber erosion just in front of the shortened cartridge to make chambering standard 375Win cartridges a problem.

Good luck!

The powders I have that I'm working with with full length loads are H322, H4198, and Reloder 7 paired with Sierra 200 gr fn bullets.

With the combination there is .351" of the sierra bullet seated into the case on a full length load. By cutting back the case and still wanting to get to COAL the bullet would only be in the case .131 which I realize is not enough. But if I seat that bullet to .231 in the case that gives me a COAL of 2.4" which may be close enough.

Ideally I find a longer bullet that I can extend out to full length. Barnes Originals would work, but I can't seem to find any. Lehigh also makes one, but I need to contact them to see if they have a bullet that will reliably expand at those lower velocities.

This could be a fun wildcat experience and hopefully resurrect a rifle that has been useless for hunting around here.

 

[dellet]

Cut the case back to just under maximum length so there is no question. Load to normal length. Take accurate measurements of the seated depth on both the bullet and where the base is located on the case neck.

Buy/use a cannelure tool to put a cannelure on the case neck to act as a stop ring for the bullet and one in the bullet to crimp into.

This is exactly how many straight wall rifle cartridges were made originally. You still find case cannelures on pistol cartridges. 357 Magnum is a good example.

If that does not prevent set back, keep the bullet straight, then start moving the bullet deeper and reducing the load.

You can make up a few inert cartridges and fill with and or other filler for weight and drop them point first onto concrete to check for recoil setback that might happen in the magazine.

 

[Hunter max-4]

Cut the case back to just under maximum length so there is no question. Load to normal length. Take accurate measurements of the seated depth on both the bullet and where the base is located on the case neck.

Buy/use a cannelure tool to put a cannelure on the case neck to act as a stop ring for the bullet and one in the bullet to crimp into.

This is exactly how many straight wall rifle cartridges were made originally. You still find case cannelures on pistol cartridges. 357 Magnum is a good example.

If that does not prevent set back, keep the bullet straight, then start moving the bullet deeper and reducing the load.

You can make up a few inert cartridges and fill with and or other filler for weight and drop them point first onto concrete to check for recoil setback that might happen in the magazine.

Not sure it is possible to load to normal length as the bullet would only be in the case .131" I think I'm going to have to either be a little short on my COAL or find some longer bullets. Not a lot of bullet choices out there in .375 diameter though.

 

[dellet]

Radical Wolf Pup Hunter BR Cartridge « Daily Bulletin

Al Nyhus and Stan Ware have created a radical short-necked Wolf Pup wildcat that won a number of matches in 2006. Al and Stan started with a 30BR design and blew the shoulder forward until the case had enough water capacity to satisfy the Hunter Benchrest rules. The Wolf Pup neck is only about .

bulletin.accurateshooter.com

You would be surprised how little neck is really needed.

The stop ring cannelure is about stoping the bullet from moving in the magazine tube, and why I suggested possibly needing to move the ring. If it were a single shot I wouldn’t even bother with that.

Your biggest problem will be fouling on follow up shots.

 

[BCBRAD]

I have done similar, with a 45-70 in a Marlin 1895.
I wanted to use a 350gn Speer but the cannalure was not positioned right for a roll crimp and maintain the factory OAL, so the bottom of the seating die was machined down so the roll crimp portion would coincide with the cannalure on the bullet, worked real well. later I took some more off and shortened the brass case further to accommodate a 500gn Hornaday round nose.
the 350's would run near 1900 ft/s and the 500's were loaded to ~1200 ft/s, powder was IMR3031.
Some reload manuals have 3 different 45-70 pressures, I used the one for a trap door Springfield.
This is not a 375 Win but process would be similar.