375 Ruger Wildcats

[Saul]

Has anyone here experimented with a 375 Ruger wildcat? I know that there are a few 375 Ruger fans on here so I am hopeful that at least one of you has gotten a little too bored at the reloading bench. I am quite impressed with the case, seeing as it is basically a slightly shorter and fatter 375 H&H without the belt and can fit in a standard length action. This got me thinking about all of the cartridges based on the the H&H parent case. I bet they would have used the Ruger as the parent if they were made today.

I have read of people necking it down to .338 and getting the performance of the 340 Wby. No more Weatherby belt or shoulder or expensive brass or magnum action. It would also be a lot better than using the RUM because it could fit in a standard action and not have a rebated rim.

I would probably start by remaking the .257 and .340 Wby using this case...maybe even make it an Ackley...

 

[USMA84DAB]

Saul -

It is not a wildcat - .375 Ruger is a SAAMI approved cartridge chambered by Savage, Ruger, Mossberg - ammo made by Hornady.

I have settled on 270 grain Barnes TSX projos.

 

[375 Ruger Fan]

I believe the 300 and 338 Ruger Compact Magnum (RCM) are based off of the 375 Ruger. Neither round really caught on.

Also, the relatively new 300 PRC is based on the 375 Ruger.

 

[Saul]

Saul -

It is not a wildcat - .375 Ruger is a SAAMI approved cartridge chambered by Savage, Ruger, Mossberg - ammo made by Hornady.

I have settled on 270 grain Barnes TSX projos.

The 375 Ruger is SAAMI, I am asking about any wildcats that use it as a parent case.

I believe the 300 and 338 Ruger Compact Magnum (RCM) are based off of the 375 Ruger. Neither round really caught on.

Also, the relatively new 300 PRC is based on the 375 Ruger.

The RCM cartridges are are around 0.5" shorter than the full 375 Ruger. The PRC is basically what I am talking about, but powder capacity is way down compared to what I have seen people getting from their 30-375 Ruger wildcats, which could be from the super long neck on the PRC or hot air on forums.

 

[fourfive8]

I think the sky's the limit for wildcats based on any original parent cartridge. The 375 Ruger had a few attributes that seemed appealing to quite few at the time it was introduced. Reasonable length, no belt and large powder capacity. If not mistaken the 375 Ruger hadn't even hit the 'show room floors' before some with close ties to Ruger were wildcatting it to 416. So it didn't take long for the 416 Ruger to be standardized.

Hot air on forums?? what, really? no way!

 

[GeoffB]

I re-barreled a friends .338 win mag in a Ruger M77 to what we now call the .458 Ruger (wildcat).
It is a .375/.416 Ruger necked up to .458". Yes it has a tiny shoulder but works a treat.
We used .416 Ruger cases as they were easier to neck up to .458"
CH4D made a set of dies from a few fired cases we sent them (took 18 months to get the dies)
This cartridge runs about 50-60 fps slower with 500gr bullets than the .458 Lott from a 24" barrel.
He has not had a chance to give it a run on Aussie buffalo yet but I am sure it will work well.

L-R .375 Ruger, .458 Ruger wildcat, .458 Lott

 

[Ray B]

The 375 Ruger resolved the manufacturing hurdles of the 375 RUM and as such, the RUM seems destined to go fairly quickly into obsolescence. There would be two versions of the Ruger that would really seal RUMs destiny. The existing standard length and possibly an H&H length for the several actions that can handle the length without adjustment. the longer versions would have the same .532" head diameter but would maintain that diameter through the web, then slight taper going forward to a shoulder of 25 -30 degrees and a 1 caliber neck. It would be basically the wildcat 375/8mm Rem Mag except there would be no step down in the case diameter for the belt.

 

[375 Ruger Fan]

I think the sky's the limit for wildcats based on any original parent cartridge. The 375 Ruger had a few attributes that seemed appealing to quite few at the time it was introduced. Reasonable length, no belt and large powder capacity. If not mistaken the 375 Ruger hadn't even hit the 'show room floors' before some with close ties to Ruger were wildcatting it to 416. So it didn't take long for the 416 Ruger to be standardized.

Hot air on forums?? what, really? no way!

I always thought Ruger missed a marketing opportunity by not calling their 416, the 416 Rugby (half Ruger, half Rigby).

 

[nztimb]

I always thought Ruger missed a marketing opportunity by not calling their 416, the 416 Rugby (half Ruger, half Rigby).

I could see a few Allblacks/Springboks/Wallabies and Puma fans being amenable to that idea.

 

[Ryan]

I re-barreled a friends .338 win mag in a Ruger M77 to what we now call the .458 Ruger (wildcat).
It is a .375/.416 Ruger necked up to .458". Yes it has a tiny shoulder but works a treat.
We used .416 Ruger cases as they were easier to neck up to .458"
CH4D made a set of dies from a few fired cases we sent them (took 18 months to get the dies)
This cartridge runs about 50-60 fps slower with 500gr bullets than the .458 Lott from a 24" barrel.
He has not had a chance to give it a run on Aussie buffalo yet but I am sure it will work well.

View attachment 349772
L-R .375 Ruger, .458 Ruger wildcat, .458 Lott

Curious, does the .458 Ruger wildcat fit in a standard action? It's a small market, but that would catch some left-handers attention for a custom in 458.

 

[GeoffB]

Curious, does the .458 Ruger wildcat fit in a standard action? It's a small market, but that would catch some left-handers attention for a custom in 458.

Yes - It fits in a standard Ruger M77 long action. i.e. any donor action for a .300 win mag, .338 win mag etc. will work.
We used an old stainless .338 win mag rifle with the plastic paddle shaped stock as the donor.
Not all bullets will fit in the magazine if they are loaded long.
The image below is a 500gr Woodleigh bullet positioned in standard Ruger long action magazine box.
This load has just over 2mm (approx 80 thou) of clearance when the bullet was seated to the middle of the cannelure. The finished rifle feed this load without any issues. We did not make any modifications to the magazine box or feed ramp apart from polishing some edges to smooth things up.

 

[R700GP100Mini14G34]

I found 3 cases labeled 6.5 MKS, 280 MKS, and 338 MKS. One source told me that the 338 was derived from a 375 Ruger, so I'm thinking that they are .375 Ruger Wildcats. Since the others have similar dimensions except for the mouth/caliber, I think they were all derived from the 375 Ruger. Rim diameters are similar to 375 Ruger. Anyone familiar with these MKS cartridges or able to tell me what MKS stands for?

 

[mooze]

I had a 9.3x375 made (AKA 9.3 Canadienne), as I could not get brass for a 9.3x64. Reamer from PTG, dies from Hornady, simple neck down procedure to make Ammo, using Hornady brass in either 375 or 416 denomination.
2 guns were made one on an AboltIII/300WM, one on an FN Mauser, both with Heym barrels at 22". I have a hard time matching 9.3x64 velocities without getting pressure signs/stuck cases.
just my urge to play.

 

[mooze]

just saw this thread was dormant for 3+ years....

 

[Luederitz]

I had a 9.3x375 made (AKA 9.3 Canadienne), as I could not get brass for a 9.3x64. Reamer from PTG, dies from Hornady, simple neck down procedure to make Ammo, using Hornady brass in either 375 or 416 denomination.
2 guns were made one on an AboltIII/300WM, one on an FN Mauser, both with Heym barrels at 22". I have a hard time matching 9.3x64 velocities without getting pressure signs/stuck cases.
just my urge to play.

Did you change from 9,3x64 to 9,3 Canadienne by changing the chamber of the existing barrels?

 

[mooze]

Did you change from 9,3x64 to 9,3 Canadienne by changing the chamber of the existing barrels?

no, I had new Heym barrels reamed. I never had a 9.3x64... dream of my youth, but not that practical. powder capacity of the 9.3CAN is about 5-8 gr more, speed is the same, but Hornady brass is quite soft, so for all practical purposes the 2 cartridges do the same.