Dear Hamish,
Exactly as you say.
I hope today arrive my 357 mag RCBS taper crimp dies (yes taper crimp), various molds and other reloading stuff. I have alredy the Rough Rider (Pietta) 357 mag model 1873 and works fine (till now just Winchester Hollow Point 110 grain White box ammo) and shoots as precise as the 9mm does.
You are rigth. Reduced loads imply automatically you MUST check if the bullet Exits the Barrel.
I experimented with home made black powder and 2 times I had to hammer out an stuck bullet from the 9mm SD9VE. 2 times I loaded 9mm with "black powder" and both times a complete failure (hammer out the bullet). Fortunatelly I can not see any damage to the rifling. The primers make burn the "black powder" but it does not burn quick enough neither has it enough energy (feels like a squib load). If only I could manage to mke Black Powder I would use just that.
I tried all Kind of stuff making "Blackpowder". KNO3 + sugar. KNO3+charcoal+sulfur (regular 75-15-10 recipe). KNO3+sugar+sulfur. It never burned quick enough and never had enough energy. I managed to load right full an 12 ga shotshell with this homemade black powder but it had a too less energy and 1 oz shot fell onto earth after 8 meters about. Seemed to have burned but Performance just was not near satisfactory. First I cooked the Blackpowder whatever the Internet said but if was dangerous and had more than one fire. So I fabricated a ball mill which works fine but the Blackpowder result was not satisfactory. So I left it and turned to scavenging shotshells (that was my backup plan) for reloading and that worked very well.
I just ordered 10000 Winchester WSP small pistol primers (are here a Little over the double of the US Price). That will last me a Long time since reloading is fairly slow with scavenging and I reload in order to be Independent and save Money.
If you have an ball mill recipe for Blackpowder what really works I would be appreciated.