Since you are feeding F/T, I would suggest that, after you thaw the mouse, take a blow dryer, or some hot water to dip in, and heat the head of the mouse to a higher temperature than the rest of its body. This method gives your snake a more natural heat picture when sizing up the mouse.

Also, while you didn't give any description of the size of your BP when compared to the size of the mice you are using, you may want to increase the size of the food that you offer your snake. It is by no means necessary, but if he can swallow the mouse folded over sideways, he can probably take on a larger sized mouse or an appropriate sized rat.

This may or may not fix your feeding situation, but I would guess that it isn't going to hurt anything.

I hope this helps.

John