I've recently found out about bumping, and my picks may have to sit out for a while...

Anyways, I have a locksmith made bumpkey and even though I've managed after trying for hours messing around using different techniques ect, managed to get my garage door deadbolt open. But, for the deadbolt on my front door. Thats a whole different story, when I insert my bumpkey, even though there is space for the shoulder to be inserted farther, and enough of the tip is filed off the key wont budge.

It's a bit stff and requires force sometimes to get any key in the somewhat old, worn deadbolt, so could this be the problem somehow? Any tips would be appreciated, as this is very puzzling.