Until about 20 years ago, it was possible to get primed .22 LR hulls from Eley in small quantities (1,000 pieces, or so).
Plenty of people experimented with BP and smokeless loads. There were even half a dozen articles in various gun rags in the '90s and early 2000s on the subject.
While it is still possible to obtain primed hulls, the minimum quantities are too great for hobby level experimentation. Last I heard (about ten years ago) on one of the small caliber forums where a few of us have dabbled in (re)loading factory rimfire, CCI's minimum order for primed hulls was quoted in the
millions -- and the cost was 80% that of loaded ammunition.
Today, primed hulls can sometimes be obtained from other sources and brands (usually ArmsCor), but I haven't found a consistent source. It seems like they're nearly always over-run lots that go to the first interested party - or highest bidder.
So, at this point, it's more realistic to buy factory ammo, pull the bullet, and do whatever it is you're going to do.
However, the real issue is a total lack of BP data.
Nah.
Establish a 4F charge that has minor compression. Seat bullet and crimp.
Standard practice aside, there
is some data available.
Between people dissecting old BP .22 LR cartridges and others developing their own loads, pretty much everyone has come to the same conclusion:
The standard charge for .22 LR with a 40 gr bullet is 4.5 gr of 4F.
Some tweaks may be necessary for different brands of powder, but that's where you start.
Here's a really good run-down put together by someone that did both of the above:
.22 LR Black Powder Adventure