A few thoughts...
1) the tong style hand reloading tool has been around a long time - since the dawn of metallic cartridges and were often included as part of a package with black powder cartridge rifles.
Buffalo hunters for example, insisted on them as they'd go into the field with a few hundred store bought cartridges, along with 25 pound kegs of black powder and a commensurate amount of lead to cast bullets and then reload their own ammunition.
At black powder pressures, with either straight wall or neck sized bottle neck cases, case life is essentially indefinite. I've been using the same batch of 45-70 cases in my reloads for over 20 years now. A wash in hot soapy water and a good drying between loads is all that is needed to keep them perfectly functional.
2) Initially the bullet mold and tong style loading tools were separate, until 1884 when Ideal included the mold on the other side of the hinge on their tong tool. With this tool, the only other things you needed were:
- a powder dipper
- a container to melt your lead in; and
- a dipper to pour the lead into the mold.
A powder dipper could usually be made by the shooter, if he had access to a file, by using a cartridge case trimmed to the length to give the required charge.
Sometimes that isn't even needed. I recall reading about one Alaska native who had hunted with one of the big gun writers at the time (1950s?) who measured the powder for his .30-30 by filling the case and scraping it off flush with the case mouth and then seating the bullet. It worked fine with that particular powder and bullet weight.
Ideal stopped putting the mold on the tool around 1900. This made sense as it was around the same time that jacketed bullet hand loading became more common.
These early tools did not have interchangeable dies and were one caliber only affairs - and with the built in bullet mold they were one bullet only affairs as well. But they were very compact and it was easy to carry a set in a saddle bag along with powder, lead, and primers, which took up less weight and space as components than a comparable quantity of loaded ammunition.
In 1947 Lyman started producing their 310 tong tool, which used different shell holders and dies, which meant a particular set of tong tools could handle a whole class of cartridges - although you still needed small and large sized tools to cover both rifle and pistol cartridges.
About 1957 Lyman switched to aluminum handles to reduce the weight, but the design has otherwise remained unchanged, and if you buy one today, you can essentially be hand loading in the same manner that shooters did in the late 1800s.
If you don't want to invest in a tong tool that requires special dies (the diameter and thread size is smaller for the Lyman 310), you can get a Lee hand press for under $35, use your regular dies and accomplish the same thing, in an almost as portable package. It's actually handy for load development at the range. For larger rifle calibers, you'll need a set of neck sizing dies to keep the manual effort to a reasonable limit.
3) Pure silver has a melting temperature of 1,761 degrees F, and a campfire isn't going to cut it. Silver coins are alloyed a bit and will melt at around 1,650 degrees, but even that is way beyond campfire range where the heat tops out at around 1500 degrees F.
Now...if you construct the fire pit in a manner that creates a draft up through the fire, then you can increase the heat significantly. This is most simply done by digging a side tunnel under and then up into the base of the fire pit - but I've never seen the Lone Ranger actually do this. You could also use a bellows to pump air into the fire, but again I've never seen Tonto running the bellows for the Lone Ranger either. It makes the silver bullet thing a bit hard to swallow, even if you can get past the reduced weight and sectional density that would have made it far less effective than lead, particularly at black powder pressures.
If you construct a coal fired forge, then you can get up around 3,500 degrees F and make your own firearm if you want to go fully off the grid.
4) Lead however is reasonably easily melted over a run of the mill campfire, particularly pure lead which melts at 621 degrees, and pure tin melts at just 450 degrees F so it's not hard to get a harder alloy. (Your household "tin foil" is actually aluminum and melts at 1,220 degrees F). Pure antimony melts at 1167 degrees F, so it's the biggest challenge over a camp fire but still do-able under ideal conditions.
5) Collodin was pretty much the first viable smokeless powder for sporting arms. It dates back to 1871, but was only produced until 1875, when the Austrian government closed the factory because it felt powder production was something that should only be done by the government. Still, while it's a real stretch, it's not out of the realm of possibility that it could have been specified in 1875 by Paladin. I have no idea what a proper charge would be. 16.9 grs is as good a guess as any, particularly for Hollywood purposes.
Poudre B, short for Powder Blanche, which translates as white powder, was the next practical powder and it didn't come along until 1884.
