6mm Lee Navy and Rifleite


#1

I bought a couple of WRACo 6mm Lee Navy FMJ cartridges a couple of weeks ago, and one had a cracked neck. I figured why not take the opportunity to see what’s inside?

I had read that the 6mm LN was loaded with Rifleite propellant, a powder originally developed for the .303 British, but (to my knowledge) never fielded with that cartridge. I have read some of the test reports of Rifleite, which suggested that it produced low velocities and high pressures, and from secondhand sources that it produced wildly inconsistent peak pressure, which (they said) probably accounted for the Winchester-Lee’s barrel life problems.

This is the powder, which I assume was Rifleite, that was loaded in my 6mm Lee Navy cartridge:

The bullet was stamped with a “W” both on the jacket:

And on the base of the lead core:

Here’s its undamaged companion:

W.R.A.Co headstamp:


#2

Thank you.

All I have to add is that is very interesting powder.
How many grains ?

Now I am tempted to look for duplicate 6mm Lee Navy rounds…

Glenn


#3

2.075g powder.

This was the later 112gr bullet version. I understand that the earliest cartridges had a 135gr bullet fired at much the same velocity as the later 112gr variant, but the Rifleite powder proved too unpredictable, so instead of switching powders (which seems to me to be the clearly superior solution), they reduced bullet weight and cartridge overall energy.


#4

Tau: Is the propellant shown consistent with descriptions of Rifleite? I ask because that general appearance–granules large in diameter and of less length than diameter–is found in a number of early U.S. smokeless powders. Jack


#5

Tau: Is the propellant shown consistent with descriptions of Rifleite? I ask because that general appearance–granules large in diameter and of less length than diameter–is found in a number of early U.S. smokeless powders. Jack

I was sort of hoping the forum could tell me. I know WRA had problems getting enough Rifleite to fulfill their orders, so perhaps some of the cartridges were loaded with another smokeless powder?

What’s really weird is their doughnut shape. I’ve never seen a powder like that before.


#6

It looks like Laflin & Rand 30 Cal…

Randy


#7

There were a number of propellants, domestic and imported, used in the first generation of American smokeless powder military and sporting rifle cartridges. I broke down two very similar-looking UMC-made 7.65 m/m Mauser cartridges and found one loaded with a powder similar to the one you’ve shown and the other containing a square flake type. The early smokeless powders for pistol use were pretty satisfactory, but developing rifle powders was a real trial. Jack


#8

Tau, the “Rifleite .303” made by the Smokeless Powder Co. would be a yellowish colored flake powder and the one you are showing is of perforated tubular shape. I agree with Randy that this is L&R WA .30 caliber powder, most probably post-1898 because it looks graphited (black color). The grains should be of 2 mm (.08") diameter and 1 mm (.04") long.


#9

It looks like Laflin & Rand 30 Cal

Oh, indeed, that powder’s description does match the powder in my cartridges.

Tau, the “Rifleite .303” made by the Smokeless Powder Co. would be a yellowish colored flake powder and the one you are showing is of perforated tubular shape. I agree with Randy that this is L&R WA .30 caliber powder, most probably post-1898 because it looks graphited (black color). The grains should be of 2 mm (.08") diameter and 1 mm (.04") long.

That’s just about how big they are.

I had heard Rifleite described as a yellowish flake powder before, but wondered if that description was wrong, since I did not know 6mm Lee Navy was loaded with anything but Rifleite.

So, the common information on the 6mm Lee Navy is that it was first loaded with a 135gr bullet, fired at 2,550 ft/s from the 1895’s 29" barrel, but the Rifleite powder used caused severe bore erosion, so they changed to a 112gr bullet fired at 2,560 ft/s. If the later 6mm Lee Navy cartridges were loaded with W.A. powder, same as the .30-40 Army, did the performance increase, perhaps? Did the barrel wear problems go away? Why didn’t the Navy switch powders sooner, or perhaps they did, and the information you normally hear is wrong?


#10

The 6mm LN is a very well balanced cartridge for today’s powders. But, it was extremely unbalanced for the powders of the turn of the century and bore erosion was a constant problem.

Ray


#11

The 6mm LN is a very well balanced cartridge for today’s powders. But, it was extremely unbalanced for the powders of the turn of the century and bore erosion was a constant problem.

Could you elaborate?


#12

The smokeless powders of the late 19th and early 20th centuries were nitroglycerine based. They were very erosive due to high operating temperatures and their chemical make up. The wearing of a barrel starts with micro cracking of the bore surface due to temperature extremes, which starts with the first rounds fired. The cracks are then burned away by the hot combustion gasses, especially in the throat and first few inches.

Couple that with a small bore (6mm), and a medium to large large case capacity, and a barrel will be “burned out” in a short time. The small bore simply cannot handle the volume of gas you are trying to force down it. Even with today’s cooler burning progressive powders, an excessively large case capacity compared to the bore size can do the same thing. The term used by most shooters for that condition is over-bore capacity. Some over-bore wildcat cartridges can destroy a barrel in as little as a couple of hundred rounds.

Ray


#13

I am interested to know more about the 6mm Lee Navy in general. Does anyone on the forum know of any good resources for further enrichment on the subject?


#14

Tau

HWS I devotes 7 full pages to the Cal .236 U.S. Navy ammunition. I’m not sure where you’d find more information on the commercial aspect. There are 4 or 5 entries listed for the IAA JOURNAL but I have no idea of their content. You’d have to get back issues or, better yet, buy the CDs.

Ray


#15

All of the smokeless rifle powders of the late 19th and early 20th century were not double-based, that is composed of nitrocellulose and nitroglycerine. The French and German propellants used in this application were typically nitrocellulose. With the double-based powders reducing the proportion of nitroglycerine reduced the tendency toward producing barrel erosion produced, over time, an improvement in barrel life. Jack


#16

Oh, excellent, thanks.