Bit by the “Wildcatter” bug!

[Wyatt Smith]

I want to do it now Bruce. I probably won’t though as I’m saving for a buffalo to shoot with my 375. But if I do why not use 8mm mag to neck up to 366 or a 358 STA that way I could more velocity or less pressure.

 

[Wyatt Smith]

Will it clear the barrel? Ha! Ha!

Yeah I think Wyatt Smith might have two of the Taylors? .375 and .416? Well if not, someone here on AH said they did? Anyway, where’s one to find 9.3 cases here in the U.S.? AND, I didn’t see .338-9.3 dies on Redding’s website? Maybe I missed it? OR, did you mean a 9.3mm (.366in) bullet in a .338 WM case (9.3-.338WM)? If so, I’m sure those bullets and reloading dies are as rare as hens teeth here in the U.S.? Maybe I’ll just look for some .465 h and h brass and neck it down to .375?

CEH I have only one 375 H&H I really like the idea of the 416 Taylor as I think a 400 grain swift a frame at 2300 FPS would be easy to achieve and give 404 like performance.

 

[CoElkHunter]

CEH I have only one 375 H&H I really like the idea of the 416 Taylor as I think a 400 grain swift a frame at 2300 FPS would be easy to achieve and give 404 like performance.

Wyatt Smith,
I too have a .375 H&H. Will I probably ever need anything larger? No. But I’ve found the larger calibers (within reason?) are fun to shoot and reload. Just something different? Besides, Bruce keeps pushing us towards more exotic stuff! Ha! Ha! Ha!
CEH

 

[fourfive8]

Since the 375 HH and 375 Ruger already exist along with the Rem UM and Weatherby versions, the idea is not to try to duplicate or compete ballistically with any of those. My thoughts for the 375-458 would simply be a shortened version of the 375 HH which would be a trouble free, easy to reload type cartridge for standard length bolt actions. One of the features of the HH case design that makes it so practical is its taper which is very forgiving for both ends of cycling... feeding and extracting. Then load to it's reasonable limits using modern powders and good bullets.

I have had two different 338-06s. Unlike the 35 Whelen which has the weakness of some headspacing issues because of minimal shoulder, the 338-06 has plenty of shoulder and does not suffer that weakness. So there is no need for the AI version. The 338-06 can still be considered a wildcat even though Norma/Weatherby make brass for it and the chamber and specs have been standardized. My idea was not to compete with the 338 Win Mag, 340 Weatherby, 338 Rem UM or 338-378 Weatherby. Quite the contrary. Currently my go-to mid-sized hunting rifle is a Win 70 in 338-06. Very easy to work up loads for, head stamped brass is available or can be made from 35 Whelen or 30-06. There is availability of a large assortment of good tough bullets because many were designed with the 338 magnums in mind. And it allows for a little more bullet than the 30-06. I have had excellent results on mid-sized PG up to wildebeest shooting either 210 or 225 gr TSXs or one of the many 225-250 gr bonded bullets available. And all at what some call boring or anemic or whatever velocities between about 2350 and 2550 fps. The longest shot was on a very good oryx broadside at about 275 yds. The trajectory that many would call poor because of the lower velocity was still practically "point blank". All I did was hold a little above midpoint on the chest instead of on the aim point at 1/3 way up the chest. A TSX hit right on the spot and was a compete pass through just at the back edge of the front leg. The oryx turned, ran straight away and fell dead at about 50 yards. All this to provide an example of a "wildcat" that is not intended to surpass or even compete with any existing cartridge yet is ultimately useful, practical and reliable. [The one bonded bullet that shoots extremely well in this 338-06 and other calibers I've shot it in is the Remington Ultra Bonded. But I dismiss it now because of a previous bad experience. It is just a weakly built bonded cup and core that will come apart on tough tissue or bone.]

So if I were to build and shoot a 375-458, I would approach it from the same standpoint as that for the 338-06.... usefulness, reliability, nice manners as to reloading and pressure sensitivity and not from the basis of ballistic hype.

 

[bruce moulds]

c.e.h.
I have 2 rifles with custom fls dies for the chambers.
the beauty of it is you can fls and only need to trim cases as much as if you were sizing necks only.
and virtually no runout.
bruce.

 

[CoElkHunter]

Since the 375 HH and 375 Ruger already exist along with the Rem UM and Weatherby versions, the idea is not to try to duplicate or compete ballistically with any of those. My thoughts for the 375-458 would simply be a shortened version of the 375 HH which would be a trouble free, easy to reload type cartridge for standard length bolt actions. One of the features of the HH case design that makes it so practical is its taper which is very forgiving for both ends of cycling... feeding and extracting. Then load to it's reasonable limits using modern powders and good bullets.

I have had two different 338-06s. Unlike the 35 Whelen which has the weakness of some headspacing issues because of minimal shoulder, the 338-06 has plenty of shoulder and does not suffer that weakness. So there is no need for the AI version. The 338-06 can still be considered a wildcat even though Norma/Weatherby make brass for it and the chamber and specs have been standardized. My idea was not to compete with the 338 Win Mag, 340 Weatherby, 338 Rem UM or 338-378 Weatherby. Quite the contrary. Currently my go-to mid-sized hunting rifle is a Win 70 in 338-06. Very easy to work up loads for, head stamped brass is available or can be made from 35 Whelen or 30-06. There is availability of a large assortment of good tough bullets because many were designed with the 338 magnums in mind. And it allows for a little more bullet than the 30-06. I have had excellent results on mid-sized PG up to wildebeest shooting either 210 or 225 gr TSXs or one of the many 225-250 gr bonded bullets available. And all at what some call boring or anemic or whatever velocities between about 2350 and 2550 fps. The longest shot was on a very good oryx broadside at about 275 yds. The trajectory that many would call poor because of the lower velocity was still practically "point blank". All I did was hold a little above midpoint on the chest instead of on the aim point at 1/3 way up the chest. A TSX hit right on the spot and was a compete pass through just at the back edge of the front leg. The oryx turned, ran straight away and fell dead at about 50 yards. All this to provide an example of a "wildcat" that is not intended to surpass or even compete with any existing cartridge yet is ultimately useful, practical and reliable. [The one bonded bullet that shoots extremely well in this 338-06 and other calibers I've shot it in is the Remington Ultra Bonded. But I dismiss it now because of a previous bad experience. It is just a weakly built bonded cup and core that will come apart on tough tissue or bone.]

So if I were to build and shoot a 375-458, I would approach it from the same standpoint as that for the 338-06.... usefulness, reliability, nice manners as to reloading and pressure sensitivity and not from the basis of ballistic hype.

I think that both the .338-06 and .35 Whelen are excellent cartridges for the person with plenty of ‘06 cases laying around. From what I’ve read, the .338-06 is more efficient than the .35 Whelen, but both are great cartridges. If you can believe it, I’ve never owned an ‘06 (except for a Garand), but have plenty of .338 brass laying around. And remember, some ammunition manufacturers did/do load a 220gr bullet for the ‘06. Better in .338 caliber!

 

[CoElkHunter]

c.e.h.
I have 2 rifles with custom fls dies for the chambers.
the beauty of it is you can fls and only need to trim cases as much as if you were sizing necks only.
and virtually no runout.
bruce.

Bruce,
I’ve very seldom fl sized fired brass in my bolt action rifles. As long as it’s being shot in the same rifle, just neck and maybe a little shoulder sizing (not usually needed though) and trimming the case and your good to go! I want to resize the case as little as possible to extend the life of the case. This would be for practice and non DG of course.
CEH

 

[bruce moulds]

c.e.h.
you have just described why factory fls dies are less than desirable.
ones made for your chamber barely size the case, and give case life up there with neck sizing.
unless you anneal necks, this is the first place cases will go when they split.
proper dies do not need an expander ball, so you work the brass less as well.
I have 6.5 super lr cases and 284 win, and 280 rem cases fl sized with decent dies fired over 20 times and still going strong.
with dies that match the chamber, you have the best of both worlds.
bruce.

 

[CoElkHunter]

c.e.h.
you have just described why factory fls dies are less than desirable.
ones made for your chamber barely size the case, and give case life up there with neck sizing.
unless you anneal necks, this is the first place cases will go when they split.
proper dies do not need an expander ball, so you work the brass less as well.
I have 6.5 super lr cases and 284 win, and 280 rem cases fl sized with decent dies fired over 20 times and still going strong.
with dies that match the chamber, you have the best of both worlds.
bruce.

Your so right Bruce! BTW the .284 and .280 are GREAT cartridges! Never owned either, but the ballistics and their cartridge efficiency look outstanding! CEH

 

[CoElkHunter]

Since the 375 HH and 375 Ruger already exist along with the Rem UM and Weatherby versions, the idea is not to try to duplicate or compete ballistically with any of those. My thoughts for the 375-458 would simply be a shortened version of the 375 HH which would be a trouble free, easy to reload type cartridge for standard length bolt actions. One of the features of the HH case design that makes it so practical is its taper which is very forgiving for both ends of cycling... feeding and extracting. Then load to it's reasonable limits using modern powders and good bullets.

I have had two different 338-06s. Unlike the 35 Whelen which has the weakness of some headspacing issues because of minimal shoulder, the 338-06 has plenty of shoulder and does not suffer that weakness. So there is no need for the AI version. The 338-06 can still be considered a wildcat even though Norma/Weatherby make brass for it and the chamber and specs have been standardized. My idea was not to compete with the 338 Win Mag, 340 Weatherby, 338 Rem UM or 338-378 Weatherby. Quite the contrary. Currently my go-to mid-sized hunting rifle is a Win 70 in 338-06. Very easy to work up loads for, head stamped brass is available or can be made from 35 Whelen or 30-06. There is availability of a large assortment of good tough bullets because many were designed with the 338 magnums in mind. And it allows for a little more bullet than the 30-06. I have had excellent results on mid-sized PG up to wildebeest shooting either 210 or 225 gr TSXs or one of the many 225-250 gr bonded bullets available. And all at what some call boring or anemic or whatever velocities between about 2350 and 2550 fps. The longest shot was on a very good oryx broadside at about 275 yds. The trajectory that many would call poor because of the lower velocity was still practically "point blank". All I did was hold a little above midpoint on the chest instead of on the aim point at 1/3 way up the chest. A TSX hit right on the spot and was a compete pass through just at the back edge of the front leg. The oryx turned, ran straight away and fell dead at about 50 yards. All this to provide an example of a "wildcat" that is not intended to surpass or even compete with any existing cartridge yet is ultimately useful, practical and reliable. [The one bonded bullet that shoots extremely well in this 338-06 and other calibers I've shot it in is the Remington Ultra Bonded. But I dismiss it now because of a previous bad experience. It is just a weakly built bonded cup and core that will come apart on tough tissue or bone.]

So if I were to build and shoot a 375-458, I would approach it from the same standpoint as that for the 338-06.... usefulness, reliability, nice manners as to reloading and pressure sensitivity and not from the basis of ballistic hype.

fourfive8,
I really like your philosophy on these “wildcat “ cartridges, in that it’s not to compete with with the current factory cartridges out there, but just to “build a better mousetrap” so to speak? A shorter or up/down chambered version of a factory cartridge with close to the same ballistics and using readily available cases that have been around forever and aren’t going to become obscure anytime soon, unlike many of the current crop of short, fat cartridges. Of course, the challenge is to be able to build or rechamber a rifle in a wildcat cartridge at a reasonable cost.
CEH

 

[Bob Nelson 35Whelen]

I'm a wildcat loonie mine as a combination of the full length 25/303, 25/30-40 krag and our 25 Tipan .
It is a 303 British necked to 25 cal, the neck has been moved forward to give me a .257 neck length, 35 degree shoulder angle and minimal taper case.
Reamer was done by Dave Manson at Manson reamer. Dies by Lee.

I won't disclose the loads publicly but will say with the 10grains ttsx I get a chronoed 3,670 fps and the 117 gn SST or 115grain nosler combined technology loaf along at 3,340fps. The powder I use is hogdon superformance. So far I get on average 8 to 10 reloads per case.

257 Roberts bottom, 257 weatherby top, 257 Epps Newton improved with 117grain SST not position of canulre. Top photo the launch platform.

200 yards target with 117gn SST

 

[bruce moulds]

well that sure outperforms both of my old 25/06 barrels.
bruce.

 

[Bob Nelson 35Whelen]

Bruce moulds
Can't understand why. Was not getting that with H4831sc 100 to 200 fps slower.
My gunsmith said the superformance burning parameters and pressure curve is longer and flatter without the usual parabolic curve. This allows the barrel to become the chamber for the gasses to exert pressure more smoothly for a longer duration..
I sort of understand him. All I need to know is I'm not pushing the envelope and it's safe.
Put round in chamber, sights on animal, pull trigger and game falls down.
2 inches high @ 100, similar @ 200, down around 2inches @300 and about 4 to 6 inches low at 400 yards. Flat enough for me.

 

[sambarhunter]

about 4 to 6 inches low at 400 yards. Flat enough for me.

4-6 @ 400 seems a bit too flat imo Bob.

 

[Bob Nelson 35Whelen]

Sambar hunter
100gn TTSX MV 3,670fps
Scope height 1.8 inch
100 yards 2inches high, 200 yards 2.8 inch high, 300 yards zero 400 7 inch low.
117gn SST MV 3,370fps
100 + 2inches, 200 yards +2.5 inch zero 275 yards, 300yards -1.4 inch, 400yards minus,10 inch.
Sorry sambar hunter must not have had my glasses on. Still flat enough for me.

 

[sambarhunter]

Got it!

 

[Bob Nelson 35Whelen]

Got it!

Sambar hunter
No worries mate where in Mexico ( sorry Vic) do you hail from. I have hunted down around the Mr Beauty area a few times beautiful country.

 

[sambarhunter]

North East ,MB is over the hill from me.

 

[Bob Nelson 35Whelen]

Sambar
I have shot sambar deer with a 444 Marlin, a 270 win and 303brit.have yet to get on with my Whelan. The 444 was over kill, I think the 35 will be as well. The 270 and old 303 worked well

 

[Bob Nelson 35Whelen]

That’s my point everything I can think of has already been done.

@wyatt Smith.
Well think outside the box. Some I have dreamed up on the 303 case t that I know haven't been done before as the mods are to my specifications.
All have a .257 neck whether 25 cal or 35 cal. All have min body taper and 35 degree shoulder to give max powder capacity and best burn character while maintaining an easy to feed and chamber cartridge.
Bob

All case capacity ous 60+ grains of powder with bullet seated 1 caliber or less.
Bob