Factory ammunition for the 41 Colt has never dried up. A lot of people don't know that but it is true. Probably about 30 years ago now some fellow in Texas had a special run made by Winchester, 1 million empty cases and 1 million rounds of ammunition. Some of the ammunition still servives. Ain't cheap and is a little hard to find but it is there. If you are interested try Huntington's or Ron Peterson Guns in Albuquerque. Huntington's has a web site but for something like this you should call.
Brass is available from Bertrums. Huntington's imports it. Not very good brass but, well, brass. Starline may have made some by now. Also Ballard Rifle & Cartridge Company does.
The problem with the 41 Colt is that it uses a heeled bullet. Except for 22 rimfire ammunition, heeled bullets are VERY uncommon these days. I don't know of any available factory bullets.
Heeled bullets are a pain because the outside diameter of the heel has to be just a fair larger than the inside diameter of the case so that when the bullet is pushed into the case it has a good friction fit. That can be a REAL challenge. It is rumored that Lee Precision now has a crimp die that works with this heeled bullet but I haven't checked that out.
Loading the 41 Colt is certainly doable BUT this isn't where I'd want to get my introduction into reloading.
