.375 Westley Richards / 9,5 x 66 SE vom Hofe - Anyone have data?

[Xpraetor]

AH Community - I am wondering if any of you Reloading Masters would have any Data / Loading Specs. for the .375 Westley Richards / 9,5 x 66 vom Hofe Super Express?

I should point out that there is conflicting details on the history of the cartridge as it has been stated that Kynoch developed the .375/303 case in 1905, and was called the Kynoch Axite; the case is referred to by various sources as the .375/303 Westley Richards Accelerated Express, but it is wrong. Westley Richards had nothing to do with the development of the Kynoch Axite .375/.303 round.
However, there is information that establishes that the Kynoch .375/.303 is not the .375 Westley Richards , as the .375 Westley Richards is in fact the 9,5 x 66 SE vom Hofe, as the firm worked with Walter Gehmann [who had purchased the rights to the vom Hofe trademark, ca. 1945] , and ammo MFG Wolfgang Romey. The partnership was established due to Westley Richards wanting a cartridge that fit into a standard Mauser Action.

The issue I am having is the conflicting data I've found - NOT internet / AI slop - one source gives the bullet diameter as .310/.311 ~ (7,9mm) , .215Gr projectile - however, I've seen, and confirmed data [IAA Forum] that has the bullet diameter as .330 ~ (8,4mm) , .250Gr - which coincidentally was used in the .318WR.
However, Westley Richards has on the books a build for a magazine gun .375 Westley Richards 300Grn Bullet.

I am aware of the fact that, in the heyday of when those rifles were built, the customer was king and it is possible a rifle would have been built to the customers specification. Despite, the 9,3 x 66 SE vom Hofe ( 9,5 = .375in) would more likely be the cartridge that has a .300Grn projectile.

What I am wondering, is the information or load data contradictory because of the confusion with the Kynoch .375/.303 vs. the 9,5x66 SE?

So, does anyone have or aware of any writings or data for the seemingly "obsolete" cartridge 9,5x66 SE - WR .375 ?

I went down a rabbit hole & hoping the savvy crew here on AH can unscramble things ....

 

[Muskox]

AI doesn't seem to have 100% firearm knowledge yet.

Most Vom Hofffes are on huge cases. Like the 404 case.

 

[PerH]

Little I’ve seen about it , is based off the 7x66 case

Find Norbert Klups book « Großwildbüchsen”
It speaks little bit about it there . I’ll dig the book up later and see .

 

[Xpraetor]

AI doesn't seem to have 100% firearm knowledge yet.

Most Vom Hofffes are on huge cases. Like the 404 case.

True, but the .375WR / 9,5 x 66 , I believe, has a rebated rim (like the .425WR), as WR wanted a .375 cartridge that would fit in a standard Mauser Action.

 

[Xpraetor]

Little I’ve seen about it , is based off the 7x66 case

Find Norbert Klups book « Großwildbüchsen”
It speaks little bit about it there . I’ll dig the book up later and see .

Thank you, yes , although I am having difficulty, as its in German, and I have yet to find a copy translated to english.
I have attempted to reach out to WR , but haven't had any luck.

 

[Luederitz]

I am shooting the 9,5x66SE vom Hofe and used it several times in Namibia on plains game with the 270 gr A-Frame.
I believe the 375 Ruger is a quite good copy and you can use the Ruger loads (max. loads are okay, the vom Hofe has a higher case capacity).

 

[Luederitz]

Here you can find cartridge drawing and dimensions:

CIP - Homologation

bobp.cip-bobp.org

https://bobp.cip-bobp.org/uploads/tdcc/tab-i/tabical-en-page73.pdf

 

[Luederitz]

From left to right
9,3x64 (250gr Accubond)
9,5x66SE (270gr A-Frame)
416 Ruger (400gr A-Frame)
450 Rigby (500gr Degol)

 

[Luederitz]

Brass is produced by SHM

Hülsenmanufaktur

Previously Horneber made brass, after he sold to Johannsen they will very likely continue in near future.

 

[Luederitz]

I am loading the 270 gr bullets with L6 = 84,5 mm, using magnum primers and 89 grains of Rottweiler R904.

Powders in the range of R904, Norma 204, N550, Reloader 17 will do.

 

[Luederitz]

Reliable on heavy game...

 

[Luederitz]

True, but the .375WR / 9,5 x 66 , I believe, has a rebated rim (like the .425WR), as WR wanted a .375 cartridge that would fit in a standard Mauser Action.

Rebated rim with diameter of 13 mm

PS: Wolfgang Romey is no longer in business

 

[Xpraetor]

Here you can find cartridge drawing and dimensions:

CIP - Homologation

bobp.cip-bobp.org

https://bobp.cip-bobp.org/uploads/tdcc/tab-i/tabical-en-page73.pdf

View attachment 779081

From left to right
9,3x64 (250gr Accubond)
9,5x66SE (270gr A-Frame)
416 Ruger (400gr A-Frame)
450 Rigby (500gr Degol)

I am loading the 270 gr bullets with L6 = 84,5 mm, using magnum primers and 89 grains of Rottweiler R904.

Powders in the range of R904, Norma 204, N550, Reloader 17 will do.

Thank you , very much for the information! The biggest issue I was having is finding powder that fit. I had found the R17 , but was unsure.

Rebated rim with diameter of 13 mm
Interesting .... so, that would be similar - in the USA - to the .300WSM or .270WSM

PS: Wolfgang Romey is no longer in business

Yes, I was aware.

I added that information, due to finding wildly contradictory information in other Forums & inter-web AI slop , and the writings I have in certain excerpts attribute the .375WR to the vom Hofe to WR collaborating w/ W. Gehmann & Wolgang Romey ammo, which seems more plausible, given the history of the .425WR development. Although, I found reference to a posting on the data for the 9,5 x 66 SE vom Hofe cartridge, and in that writing it states the "9,5 v. Hofe was conceived by August Schüler & a member of the vom Hofe family...."

In addition the posting gives--

Primer size: LRM
Case Capacity: 106 Grn water
Bullet/Bbl Dia. : .375" / 9.52mm
Max Case : 2.598" / 65.99mm
Max Cart. : 3.35" /85.09mm
Max Std Prs : 63817 / 4400bar

But no information on powder or bullet weight(s).

Again, I grratly appreciate all of the information you provided.

 

[Xpraetor]

Reliable on heavy game...
View attachment 779084View attachment 779085

Very Nice!

 

[Jefferry404]

@Xpraetor
this one

Westley Richards .375 Westley Richards (9.5×66 SE). Based on a Mauser 98 action.
Thirty six rounds of Westley Richards ammo (10 rounds of 300-grain solids and 26 rounds of 300-grain softs) is included. Case head markings are 9.5×66 SE, W. Gehmann

 

[Jefferry404]

@Xpraetor
I have good success using QL and Hodgdon Reload data for obsolete, obscure cartridges by fitting data to a known cartridge with similar case capacity, load density (if greater than 100%) and similar PSI. Gives a good starting point.
If i was to reload for the 375WR, my starting load would be 73.0gn Varget with 300gn Woodleigh SP for 2557fps, 55.6Kpsi and 89% LD. I used Varget as it gave a good starting load density with room to add more powder up to about 92%.

 

[Sarg]

AH Community - I am wondering if any of you Reloading Masters would have any Data / Loading Specs. for the .375 Westley Richards / 9,5 x 66 vom Hofe Super Express?

I should point out that there is conflicting details on the history of the cartridge as it has been stated that Kynoch developed the .375/303 case in 1905, and was called the Kynoch Axite; the case is referred to by various sources as the .375/303 Westley Richards Accelerated Express, but it is wrong. Westley Richards had nothing to do with the development of the Kynoch Axite .375/.303 round.
However, there is information that establishes that the Kynoch .375/.303 is not the .375 Westley Richards , as the .375 Westley Richards is in fact the 9,5 x 66 SE vom Hofe, as the firm worked with Walter Gehmann [who had purchased the rights to the vom Hofe trademark, ca. 1945] , and ammo MFG Wolfgang Romey. The partnership was established due to Westley Richards wanting a cartridge that fit into a standard Mauser Action.

The issue I am having is the conflicting data I've found - NOT internet / AI slop - one source gives the bullet diameter as .310/.311 ~ (7,9mm) , .215Gr projectile - however, I've seen, and confirmed data [IAA Forum] that has the bullet diameter as .330 ~ (8,4mm) , .250Gr - which coincidentally was used in the .318WR.
However, Westley Richards has on the books a build for a magazine gun .375 Westley Richards 300Grn Bullet.

I am aware of the fact that, in the heyday of when those rifles were built, the customer was king and it is possible a rifle would have been built to the customers specification. Despite, the 9,3 x 66 SE vom Hofe ( 9,5 = .375in) would more likely be the cartridge that has a .300Grn projectile.

What I am wondering, is the information or load data contradictory because of the confusion with the Kynoch .375/.303 vs. the 9,5x66 SE?

So, does anyone have or aware of any writings or data for the seemingly "obsolete" cartridge 9,5x66 SE - WR .375 ?

I went down a rabbit hole & hoping the savvy crew here on AH can unscramble things ....


View attachment 778978

I think you are mentioning 3 different cartridges in your post so that could be part of your confusion.

Unfortunately I don’t have information on the one I think you need which is the 9.5x66 Von Hofe is this the one you have & want load info for ?

Westley Richards did invent the .375Ex 2 1/2in which looks like a blown out straight 303 Brit case but longer & some get confused & call it the Velopex, which is a different short .375 by H&H also called.400/375 first belted case.

I have cartridges & rifles for both but away from home right now.

The WR .375Ex 2 1/2in Flanged looks like this .

The other Cartrigde you mentioned is the .375/303 Axite
Which is a .303 projectile in a much larger case, I suspect a .300 or .375 Flanged Magnum case, I have a few of these cases at home but havent measured them to know for sure, but you get the idea not a .375 caliber cartridge.

It looks like this, like a over sized ,303 Brit cartridge.

 

[Xpraetor]

@Xpraetor
this one
View attachment 779116

Westley Richards .375 Westley Richards (9.5×66 SE). Based on a Mauser 98 action.
Thirty six rounds of Westley Richards ammo (10 rounds of 300-grain solids and 26 rounds of 300-grain softs) is included. Case head markings are 9.5×66 SE, W. Gehmann

Is that a .375WR? That is very similar to the .425WR magazine rifle....

 

[Xpraetor]

@Xpraetor
I have good success using QL and Hodgdon Reload data for obsolete, obscure cartridges by fitting data to a known cartridge with similar case capacity, load density (if greater than 100%) and similar PSI. Gives a good starting point.
If i was to reload for the 375WR, my starting load would be 73.0gn Varget with 300gn Woodleigh SP for 2557fps, 55.6Kpsi and 89% LD. I used Varget as it gave a good starting load density with room to add more powder up to about 92%.

Thank you for that load Info. , done some reading that has mentioned all 3 of the WR cartridges - .318 , .375 & .425 , it started me to researching & then the conflicting history made it difficult to figure load data. @Luederitz , was also gracious enough to provide load data, as he shoots the 9,3 x 66 SE.

So thank you very much

 

[Jefferry404]

The text below the pic was from the seller, not from me, was listed at $24k Nice rifle, great wood, etc