5.6x50 Chamber

[Stephen Cohen]

I have access to both 222 Remington Mag and 223 Reamers, can these reamers be driven deeper into barrel to allow the use of 5.6x50 brass without getting the web area of fired case enlarged. I know I may well have to trim case necks a little but as this is a custom Martini Rifle and I will be using 5.6x50R brass which I already have I don't mind a little brass work. I should mention the barrel I will use is already chambered for 223. Any help and advice will be appreciated. Regards Stephen.

[Bent Ramrod]

I would get a piece of clear plastic rod, drill a pilot hole with maybe a #2 drill, and “chamber” it with your .222Magnum reamer. Go slowly, using WD-40 and keeping the everything cool so the plastic cuts, rather than melting.

Run it deep enough so you can cut a rim seat to the proper depth with a regular lathe tool, and see how well a sized 5.6x50R drops in and fits.

I routinely check my purchased, rented and homemade reamers and D-bits this way for the possibility of burrs and dull spots on the cutting edges that might produce chamber rings, and to see if makeshift cases will work in the chambers: how short, long, over/undersized at base, etc, they are.

Gives me a better visual than cutting a chamber in a scrap piece of steel, and doesn’t violate the “one chamber only” rental agreement that is frequently imposed by the rental company. At least in spirit, anyway.