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johnm1 · December 25, 2011, 08:29 PM

Nick,

You always seem to answer my questions. Hope the holiday season has been good to you and your family.

I figured the common 8x56R used in the plentiful M95 carbines would size down to the 8x50. I am a little concerned with rebound but the sizing die is another $90 and if I can avoid that cost I would prefer to do so. In the end, if I need the sizing die I will get it.

This is an odd little cartridge. The original 8x50R bullet diameter was 3.23/24 and the bottom of the grooves in the barrel were cut to 3.30. The bullet design of the day had the bullet riding the lands and the base was designed to expand to seal the bore. The newer 8x56R was designed with a .329 boat tail as I figure the newer spitzer bullets base would not expand to seal the bore. A shorter lighter bullet with a boat tail design would have less contact area, relatively, in the barrel and a load was finally designed for it. From what I read on the internet the 8x56R round carries quite a punch so I figure the receiver is pretty stout.

There is some conversation on the internet about developing loads for the 8x50R and I am still reading them. I don't need a full house round for this rifle. I just want to have something to shoot informally and take to at least one match. Although I have been reloading for close to 30 years (big break when the kids were young) I only started loading for rifles early this year. It appears that a cast bullet is probably the wisest bullet selection but I have never loaded for a cast bullet with a gas check. I have this underlying fear that I'll leave a gas check in the barrel. I suppose I can learn more about loading cast bullets for a rifle and address my concerns.

That being said I want to start with a load using a .329/.330 jacketed bullet like the 8x56R does. Something with a round profile to reproduce the original dimensions of a loaded cartridge as closely as possible. This will be to aid in feeding as I understand that when the caliber was changed to 8x56R on these rifles/carbins the magazine was altered slightly to change the angle the cartridges left the magazine. Velcity is not important other than to try to get something that will utilize the sighting system on the rifle. I figure if I start low enough I should be able to avoid catastrophe. One concern is the actual chamber dimension where the neck of the case rests. Being it was originally machined for a bullet of .323/24, a bullet of .329/.330 may not chamber. Again, when these rifles/carbines was rechambered I understand a step was machined into the chamber at that location to allow for the larger diameter bullet. I can test this during load development. There is some pretty interesting reading on Yesterday's Weapons Forum by gschwertley on this cartridge.

So the real question is can I safely develop a load using the .329/.330 bullets?

December 25, 2011, 08:29 PM	#3
johnm1 Senior Member Join Date: November 26, 2006 Location: Mesa, AZ Posts: 652	Nick, You always seem to answer my questions. Hope the holiday season has been good to you and your family. I figured the common 8x56R used in the plentiful M95 carbines would size down to the 8x50. I am a little concerned with rebound but the sizing die is another $90 and if I can avoid that cost I would prefer to do so. In the end, if I need the sizing die I will get it. This is an odd little cartridge. The original 8x50R bullet diameter was 3.23/24 and the bottom of the grooves in the barrel were cut to 3.30. The bullet design of the day had the bullet riding the lands and the base was designed to expand to seal the bore. The newer 8x56R was designed with a .329 boat tail as I figure the newer spitzer bullets base would not expand to seal the bore. A shorter lighter bullet with a boat tail design would have less contact area, relatively, in the barrel and a load was finally designed for it. From what I read on the internet the 8x56R round carries quite a punch so I figure the receiver is pretty stout. There is some conversation on the internet about developing loads for the 8x50R and I am still reading them. I don't need a full house round for this rifle. I just want to have something to shoot informally and take to at least one match. Although I have been reloading for close to 30 years (big break when the kids were young) I only started loading for rifles early this year. It appears that a cast bullet is probably the wisest bullet selection but I have never loaded for a cast bullet with a gas check. I have this underlying fear that I'll leave a gas check in the barrel. I suppose I can learn more about loading cast bullets for a rifle and address my concerns. That being said I want to start with a load using a .329/.330 jacketed bullet like the 8x56R does. Something with a round profile to reproduce the original dimensions of a loaded cartridge as closely as possible. This will be to aid in feeding as I understand that when the caliber was changed to 8x56R on these rifles/carbins the magazine was altered slightly to change the angle the cartridges left the magazine. Velcity is not important other than to try to get something that will utilize the sighting system on the rifle. I figure if I start low enough I should be able to avoid catastrophe. One concern is the actual chamber dimension where the neck of the case rests. Being it was originally machined for a bullet of .323/24, a bullet of .329/.330 may not chamber. Again, when these rifles/carbines was rechambered I understand a step was machined into the chamber at that location to allow for the larger diameter bullet. I can test this during load development. There is some pretty interesting reading on Yesterday's Weapons Forum by gschwertley on this cartridge. So the real question is can I safely develop a load using the .329/.330 bullets? __________________ John M. Mesa, AZ