|
Can't remember right now where I read it but somewhere says that if you want to enchant a weapon with a specific magical ability (for example the Flametongue's ability to shoot a fiery ray once per day) you can make like a "reverse engineering" on the price of the specific magic weapon removing the price for normal magical abilities and enhancements, and the price for the masterwork weapon (of course, DM discretion applies).
For example, the Flametongue costs 20,715gp and is a +1 flaming burst longsword that once per day can shoot a fiery ray, if we remove the price of the +1 flaming burst (18,000gp) and the price of the masterwork longsword (315gp) we are left with what is supposed to be the price for the specific magical ability (2,400gp).
So technically you can do the same with the Pistol of Infinite Sky, that specific weapon is a +5 pistol that never needs reloading (unlimited ammo always loaded gun), it costs 73,300gp, if we remove the price for the +5 enhancement (50,000gp) and the price for the masterwork pistol (1,300gp) we would have the price for the specific magical ability (22,000gp).
So (with your DMs approval) you could pay 22,000gp to add that specific magical ability to your +1 musket, or if you have Craft Magic Arms and Armors pay 11,000gp to enchant it yourself.
I’ll mention again that I can’t point out exactly where I read this or if it’s even part of the actual rules, but at least the idea and process itself makes sense to me.