I had purchased a very expensive pair of leather boots, and they fit fine on my calves, but I needed them to fit over a pair of tapered bottom jeans as well.  I used stretching spray, and then stretched the boot shafts for 36 hours.

Worked like a charm!  Worth every penny - cobblers are expensive, and a couple told me that you CANNOT stretch boot shafts.  HUH??  Since, I've used this on a couple other pair, making old shoes new again, since with each child, my feet grew a half inch!

I also got a toe box stretcher, which added even more forgotten about shoes to the wearable mix.

Top quality, you won't be sorry!!