What size lube patch to use on a 69. cal.

[Gettysburg63]

I have a .662 mould that I am using to cast musket balls I was wondering what size lube patch I could use?

Thank you

 

[Alden]

Is this a trick question?

 

[Wes/Tex]

Patch has to be at least half the ball's circumference, which in your case is 2.08"...and that's minimum! Anything bigger is gravy...round, square or octagonal, your choice! :wink:

 

[Zonie]

Uh, I think you might have forgot to divide by two?

Half of the circumference of a .662 ball is 1.040.

Actually, to make centering the patch on the muzzle easier the patch should be about 1 5/8 to 1 3/4 diameter or a square of that size.

 

[mcritelgmail.com]

Is that a rifled 69 musket?

 

[Zonie]

The 2.08 and 1.04 figures are the circumference of a .662 diameter ball or half that amount.

Those sizes really wouldn't work because it would be darn near impossible to position the patch so it fully covered half the ball.
Any error in centering a patch that size would result in some area that wouldn't have a patch between the ball and the bore.

IMO, this patch size thing isn't real critical as long as there is patching all the way around the ball where it meets the bore.

For a quick calculation to figure out a good patch size just multiply the ball diameter times 3.

If cloth is at a premium or a smaller size is wanted, multiply the ball diameter times 2.5.

If someone wants my theoretically accurate patch size, multiply the diameter of the ball times 3.142. Divide the answer by 2. Then, add in the diameter of the ball.

For a .66 diameter ball the answer for the first method would be 1.980.
For the same ball the answer for the second method would be 1.650.
For the theoretically correct answer the size would be 1.697.

Any of these three answers will work fine.

 

[Billnpatti]

A patch measuring about 1 3/4 inches in diameter will work quite nicely for your .69 cal. For target shooting, plain old spit works wonders as a lube and is my favorite in most of my guns. Just put the patch in your mouth for a few seconds to get it wet. Just wet is all you want, you don't want it dripping slobbers. For hunting, something like Bore Butter is a good choice although many people like straight Ballistol or something like olive oil. Don't use too much, just a drop or two (literally) is plenty. While light lubing gives improved accuracy, it also requires wiping between shots with a damp patch. A good mixture for wiping is 1 part Pinesol, 1 part Ballistol and 10 parts water. Dampen your patches with it and run a patch down to the breach in one single stroke (no pumping) and then remove it with one single stroke. It will keep your bore the same from shot to shot and keep your groups nice and tight.

 

[nkbj]

The biggest consideration for pre-cut patches is always how much clearance you have for the material bunching up around the rod.
With a .69 I don't run into a problem with that because the bore is so much bigger than the diameter of the straight part of the jag and rod. And, don't figger you will either.
That said, the bore diameter times three works great and it can be reduced as you see fit.