The current 10 ounce denim here, measures with my calipers, hard compressed, is .021". The last 4 meters I purchased prior to this bunch, measure with the same calipers at
.0225". So - there is some thickness difference, depending on the mfgr'.
This is for 100% cotton, no man-made fabrics included, although some denim does have these, but they are marked on the bolt label.
Always use 100% cotton or 100% linen, no matter what patching you use - no synthetics. If you pull a few fibers free and light them, they will burn cleanly, it's no melting - and where you snuff
it out with your fingers, only chared cloth remains, no hard deposits in the burn section, only soft charred cloth.
We were able, years ago now, to find a 100% cotton mattress ticking, that measure in those same calipers at .0235". it was wonderful material and I am almost out of it - just a few scraps left.
I used that stuff in my .40 Goodoien Barrel with a .395 as well as the .400" balls. Used it in the .45 GM bl. with .445" balls, in my .32 with .311" and .320" balls as well as the .50, with .495" balls.
I use the .0225" denim in all of those as well, with the same .005" under sized as well as the bore sized balls. My current .021" 10 ounce denim patches work just fine with the .495" ball in the
Beck .50 with Rice Gun Maker's bl. as well as my new Rice .36 with the .350" AND some .360" balls I purchased at Hefley, 2 years ago. Those were my best groups on the last postal match. .360"
ball and .021" 10 ounce denim patch. I was using spit, but lube really didn't matter. Any of the oils or greases I've used, loads easier than spit or a water based lubes. With a small bore and the
mink oil, loaded gets easier after the first shot, that is, the 2nd through 50th are easier, but about the same as the 2nd and 3rd.
In my big bore, I found 12 ounce and 14 ounce denims to give the best accuracy, in that one, I use .682" as well as .675" balls.