Morning. Pursuant to your Whitworth question about paper. I am not expert but have successfully casted and paper patched several hundred. Some of my lessons learned.
Paper. I researched Borden and Riley sketch paper 8 lb and been using that.
The bullet: Whitworth bullet is different as we know and but patching is pretty much the same as conical. I would not waste money for a template as in my opinion a good paper cutter is all you need. I tried two methods of cutting paper. The diagonal end cut with two wraps works good with conical but is a challenge with a hex bullet. I found just a straight cut and two wraps works just as well in trying to get the bitter ends to match up when wrapping bullet.
Wrapping: I initially tried the ytube method of just damping patch and wrapping. I found getting paper wet ( I use soaking wet dollar store cotton makeup swabs) And the age old question: do you wrap with the rifling as the bullet leaves barrel or wrap with the rifling going so paper tighten going in. I use wrapping with rifling going in while loading. As far as mechanics of actual doing this, Well only learning through you own experience. No one can tell you every lesson learned or pitfall. After wrapping bullets and twisting end I allow to dry overnight. (a 45 colt ammo box works good and put them in nose first) Next day I dampen patched bullets again and put in racks in air dryer and run about 2 hours at about 180 degrees. This tightens paper like a snare drum. Don't forget to snip twist end of patch
Loading and shooting: Depending on type of gun (I have Parker Hale) first two shots the bullet will load quite easy and slide down barrel. I finger lube each bullet as I load using a homemade lube of bees wax and olive oil and other stuff. And about the viscosity of bore butter on a warm day. After first shot you will find you gotta swab barrel after every shot. Whitworth barrel likes to be clean for loading and accuracy. Another lesson learned is swabbing barrel. Do NOT use regular brushes or jags. My Whitworth seems to have a breech ridge and using conventional jag with cleaning patch may cause rod to hang up in breech. Hang up so bad you may break something off in barrel. (ask me how I know) I use a shotgun brass brush ( .410 gage I think) and wrap a custom made cleaning patch over it. The patch sticks like glue to brush and does not get stuck in breech. For patch material I use Walmart pre-cut diaper material/fabric
There is another book here of info but the big pitfall is getting cleaning rods stuck in breech area. Your gun may be different. Anyway, I am not expert but know the Whitworth will out shoot just about anything out there and the extra ‘ah shucks’ we experience are worth the steel clanging at 800 meters.
If you have any question feel free to PM me your number. Jerry