I don't use that method, but it ought to be possible to fire at the ground where there's an uphill slope so misses won't go as far. Aiming at a target (such as a tree or the wall of your cabin) results in a very high breakage rate, which isn't practical (I don't think stones count as arrow breaking targets, but haven't tried to test if they are).
I think I've seen somewhere that firing at dead targets require the distance to be at least 5 tile, though I can't confirm if it's correct.
The gamey method I use is to fire blunt arrows at prey caught in bear traps, aiming for the head.
Regardless of method, increasing weapon skills is a very slow process, especially when above 90% (I've definitely had several cases of more than 600 consecutive failures to increase skills at that level, although that was dodge and shield use)