Re-Barreling an M1896 Mauser

sheepherder · 08-25-2014, 08:56 PM

Re-barreling an M1896 Mauser

(Part two)

Reaming the C96 barrel for a .256 bottleneck cartridge

(This part presupposes that you have already installed a .256 caliber barrel blank on your Broomhandle). I'll be forming a wildcat cartridge out of .223 Rem unprimed brass, using shortened RCBS .256 Win Mag dies to make a .256 caliber bottleneck cartridge with the same OAL as the 30 Mauser cartridge..

First, we have to make the cartridge. I used a set of .256 Win Mag dies, shortened .185". I used a carbide cutter, low speed, and low feed. Shown is a finished brass cartridge, the dies before shortening, and a loaded cartridge with 60 gr soft nose bullet.

Cutting down the die; removing three threads as OEM RCBS die set...

Chamfering the base of the die with a 'fine' grit pyramid stone...

The finished shortened dies, and the shortening steps in the .223 Rem cartridges we're forming with them...

Now that I have a cartridge, I can ream out the barrel. I'm going to do it a bit backwards from my usual practice, with the reamer/extension/floating reamer holder held in the chuck and the barrel extension clamped to an angle plate. Plate is squared and extension leveled and centered to the reamer/chuck center. Reamer shown in position. Solid pilot Clymer .256 Win Mag straight flute chamber finishing reamer.

Starting the cuts...1/32" at a time, using high-Sulphur content cutting oil; squirt oil in, back out, blow off chips, repeat...

Taking a rough measurement, using stripped bolt and finished/formed unprimed dud cartridge...

Cutting some more...

Now I'm down to .050" from zero headspace...Lots of oil and chips...

Down to zero headspace. Now I run the reamer in an additional .004"...

A box of headspace dots, punched out of plastic shim stock...

The .004" dot on the bolt face. It's a blue dot; the flash makes it look white. I don't have any white dots...

And with the .004" dot in place, I have no movement. Reaming is done. Barrel is headspaced.

Some pics of the finished chamber...

Overall view...

And a pic of the old/long .256 barrel stub, showing how much
supported tube is threaded into the extension...

The new chamber still needs to have the extractor notch cut, and the feedramp cut & smoothed.

I did a similar long-barrel/re-barrel in .256 caliber some years ago...I really liked it, but finding a shoulder stock the long-barreled Mauser will fit into has been unsuccessful...

08-25-2014, 08:56 PM	#2
sheepherder Lifer Lifetime Forum Patron Join Date: Feb 2009 Location: ...on the 'ol Erie Canal... Posts: 8,208 Thanks: 1,425 Thanked 4,474 Times in 2,343 Posts	Re-Barreling an M1896 Mauser Re-barreling an M1896 Mauser (Part two) Reaming the C96 barrel for a .256 bottleneck cartridge (This part presupposes that you have already installed a .256 caliber barrel blank on your Broomhandle). I'll be forming a wildcat cartridge out of .223 Rem unprimed brass, using shortened RCBS .256 Win Mag dies to make a .256 caliber bottleneck cartridge with the same OAL as the 30 Mauser cartridge.. First, we have to make the cartridge. I used a set of .256 Win Mag dies, shortened .185". I used a carbide cutter, low speed, and low feed. Shown is a finished brass cartridge, the dies before shortening, and a loaded cartridge with 60 gr soft nose bullet. Cutting down the die; removing three threads as OEM RCBS die set... Chamfering the base of the die with a 'fine' grit pyramid stone... The finished shortened dies, and the shortening steps in the .223 Rem cartridges we're forming with them... Now that I have a cartridge, I can ream out the barrel. I'm going to do it a bit backwards from my usual practice, with the reamer/extension/floating reamer holder held in the chuck and the barrel extension clamped to an angle plate. Plate is squared and extension leveled and centered to the reamer/chuck center. Reamer shown in position. Solid pilot Clymer .256 Win Mag straight flute chamber finishing reamer. Starting the cuts...1/32" at a time, using high-Sulphur content cutting oil; squirt oil in, back out, blow off chips, repeat... Taking a rough measurement, using stripped bolt and finished/formed unprimed dud cartridge... Cutting some more... Now I'm down to .050" from zero headspace...Lots of oil and chips... Down to zero headspace. Now I run the reamer in an additional .004"... A box of headspace dots, punched out of plastic shim stock... The .004" dot on the bolt face. It's a blue dot; the flash makes it look white. I don't have any white dots... And with the .004" dot in place, I have no movement. Reaming is done. Barrel is headspaced. Some pics of the finished chamber... Overall view... And a pic of the old/long .256 barrel stub, showing how much supported tube is threaded into the extension... The new chamber still needs to have the extractor notch cut, and the feedramp cut & smoothed. I did a similar long-barrel/re-barrel in .256 caliber some years ago...I really liked it, but finding a shoulder stock the long-barreled Mauser will fit into has been unsuccessful... __________________ I like my coffee the way I like my women... ...Cold and bitter... Last edited by sheepherder; 09-08-2014 at 07:05 PM.