One-handed reloading of a pistol crossbow?

[Rupert]

Originally Posted by Varyon

A crossbow scaled to your ST isn't going to be able to reloaded with one hand, at least not without mechanical assistance such as a goat's foot, winch, etc, because you need the strength of both arms to draw it back.

Unless it has a foot stirrup, in which case you're using the strength of your leg(s), not your arms.

Also, you can load a crossbow of ST+2, so one handed would be 0.7 times ST+2. I'd be inclined to simplify this to 'can load at up to your ST by taking twice as long' and be done with it.