Bolt gun in .375 Flanged Magnum

549

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As I understand it, the cartridge is based on the .303 British. Maybe a converted Enfield?

Why? Just ‘cause. :)
 
The 375 Flanged NE is based on the 303. The 375 Flanged Magnum is not.

A hunting cartridge produced for single-shot and double rifles, the .375 Flanged NE is a slightly longer version of the .303 British necked out to .375 caliber. The .375 Flanged Nitro Express should not be confused with the .375 Flanged Magnum, a much longer and more powerful all-round African hunting cartridge.
 
I have a few of these the .375EX 2 1/2in in WR Styer & Lee Speeds / Lee - Metfords/Enfields it is a powerful cartridge & under rated, has a bit of recoil in light rifles with top loads with 270-320gr bullets.

Not based on the .303 Brit cartridge, it can be used to form way short cases but is not right.

I had both the 375/303Brit & .400Brit (.40 Maynard?) which are cool to play with on Lee Enfields & Martini rifles !

Was my idea to fit a .405Win into a Lee Speed many years back !
 
The 375 Flanged NE is based on the 303. The 375 Flanged Magnum is not.

A hunting cartridge produced for single-shot and double rifles, the .375 Flanged NE is a slightly longer version of the .303 British necked out to .375 caliber. The .375 Flanged Nitro Express should not be confused with the .375 Flanged Magnum, a much longer and more powerful all-round African hunting cartridge.
You're correct!

I'm was thinking a P14 would be a likely suspect to chamber the Flanged Magnum in as I believe it can handle long cartridges and the bolt face is wide enough to not need serious modification as the rim diameter of the .303 is close to that of the .375 Flanged Magnum.

I'd have to find a gunsmith willing and able to cut & reconfigure it externally.

This merely a mental exercise at this point.
 
I have a few of these the .375EX 2 1/2in in WR Styer & Lee Speeds / Lee - Metfords/Enfields it is a powerful cartridge & under rated, has a bit of recoil in light rifles with top loads with 270-320gr bullets.

Not based on the .303 Brit cartridge, it can be used to form way short cases but is not right.

I had both the 375/303Brit & .400Brit (.40 Maynard?) which are cool to play with on Lee Enfields & Martini rifles !

Was my idea to fit a .405Win into a Lee Speed many years back !
I've never heard of the .375/303 Brit. or .400 Brit. Looks like some research is in order, if only for curiosity sake.
 
549,
to fit the 375 HH Flanged Magnum into a P14 ( probably the only action for this conversion ) takes a lot of modifications to the action.
I converted a P14 to 9.3x74R ( slightly longer than the 375 ) and it involves a lot of metal removal, new mag box, etc, etc, and on and on....
There are only two of these sorts of conversion that I know of, mine and Young Finn's in South Africa...his being on a slant box Rigby action.
To pay someone to do this conversion would be extremely costly, just for the metal work alone....I am not trying to discourage you, just the facts.

Roger
 
Just for clarification...
The 375 x 2-1/2" flanged nitro express is the " 303 " style cartridge, the two and a half inch length being the identifier.

The 375 H &H Flanged Magnum is the rimmed version of the Holland and Holland 375 Magnum.

Roger
 
549,
to fit the 375 HH Flanged Magnum into a P14 ( probably the only action for this conversion ) takes a lot of modifications to the action.
I converted a P14 to 9.3x74R ( slightly longer than the 375 ) and it involves a lot of metal removal, new mag box, etc, etc, and on and on....
There are only two of these sorts of conversion that I know of, mine and Young Finn's in South Africa...his being on a slant box Rigby action.
To pay someone to do this conversion would be extremely costly, just for the metal work alone....I am not trying to discourage you, just the facts.

Roger
Indeed it would be. Plus, it seems that loaded .375 Flanged Magnum ammo is non-existent now. Whether it's just something that's run off occasionally or something that the ammo makers have permanently discontinued, IDK.
 
The 375 Flanged is to 375 Flanged Magnum (and 375 HH), as the 9.3x57 is to 9.3x62.

Soft shooting, low pressure cartridge that is flinging 375 bullets at modest velocities, on a necked out 303.

Still a great hunting cartridge I would think, but it's a long way away from the 375 HH.

The 375/303 is another cartridge altogether. The 375 Flanged Magnum necked down to shoot .311 303 bullets.
 
Last edited:
OxfordTheCat, the 375 x 2-1/2 FNE is not a " necked out 303 " it is a completely different case, based on the 303 but longer.
The 375/303 IS a " necked out 303 "......the last sentence makes no sense....I apologise if this sounds rude.
 

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