6mm Lee Navy Cartridge Dimensions

[Hip's Ax]

Greetings, anyone know where I can get my hands on a cartridge drawing for 6mm Lee Navy? I have Myszkowski's book and it has some dimensions in tabular form but I'd really like a drawing.

Also, anyone know where I might buy one or more rounds of original military or commercial ammo for measurement purposes? Having one or a few rounds (different vintages) of correct ammo would help me figure some things out.

This helped me out a LOT in figuring my Arisaka rifles out. (MAN what a chore that was!)

Thank You!

Information

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[Parashooter]

I can't vouch for this drawing, borrowed from the Quickload software package. Body diameter ahead of cannelure seems small. A chamber cast from an original rifle would be a better source. Picture below seems to demonstrate that the 6mm Lee was essentially a rimless .30/40, necked down. That would certainly make sense from a manufacturing perspective.

[Hip's Ax]

Thanks Parashooter. I will make a chamber cast as well as measure and read everything I can find. I should have known you'd have the drawing.

Thanks!!!

[OlManDow]

That body diameter really is correct. You can make usable Lee ammo by turning the rim of 220 Swift ammo to .443 and just necking it up to 6mm. It will be a bit short, but works fine. You will find the dimensions of the fired cases are almost indistinguishable form the unfired Swift brass except for the expanded neck. The head diameter is shared with the 6.5mm MS and the 6.5 Carcano, but there is nothing available long enough to make full length cases - the Swift is closest. I have tried swaging down 30/40 Krag cases, but that is real work. The solid head doesn't want to be swaged down a full 14 thousandths or so. You could turn the belt off 240 Weatherby cases, but they are hard to find and expensive.

Rifling twist is really fast so don't expect any accuracy from bullets lighter than 110 grains - if you can find the 105, 110 or 115 gr round nose bullets that Hornady and Barnes used to make, they work best. Otherwise, try the 105 gr. AMAX. By the way, you can make a size die by boring out the neck of a 220 Swift die with a carbide die drill, and avoid the cost of those custom dies.

OlManDow

[cquickel]

This weekend I found an old cartridge that looks like a 6mm. It is marked "SMT 954" or "054" on the end. Any ideas?

[andiarisaka]

Here are links to couple more drawings, one the 6mm Lee http://ammoguide.com/?catid=25, and the other the 6mm Swift http://ammoguide.com/?catid=500 The only differences of course are the rim diameter, neck length, and shoulder angle. For members of ammoguide there's also a couple loads there for a 112 bullet.