Does anyone have any information on the 375 Nitro 2.5"?

The rifle it is chambered for is a pre war Mauser 98. It has the following stamps on the barrel and receiver:

375 Nitro, 280gr, NC 38gr
9.5mm (375) x 2.5"
9.5mm x 63mm
British Proof marks
Not English made
Specially made for Chas. A. Heyer & Co. Nairobi
Waffenfaerik - Oberndorf
A/ n. (the n. is underneath the A and in small font)


The previous owner has once fired brass headstamped "Norma RE special" The once fired brass measures aprox.:

rim .468"
rim thickness .046-.050"
base dia. .468"
dist. from base to top of shoulder 2.011"
case length 2.485"

He also had some reload formed from 280 Rem. brass.


I have not been able to find any reference to this cartridge. Any information would be appreciated.

hi..

try to get in touch with kynoch,their site seems to be down for the min,but im sure you can get it from google,or does anyone on here have their number? i have it somewhere,just not sure precisely where!

cheers

zac m.

Every thing you write makes sense to me except the 9.5x63 stamp. I have a Mannlicher 1908 in 9x56 Mannlicher that has the same chamber dimentions as you quote. I believe it is the same as the .375 Nitro 2.5" rimless. My rifle shoots a 270 grain bullet at 2200 fps and is about as accurate as I can shoot with iron sights.