In respect of drilling holes in bronze etc that tend to grab, it is entirely possible that the drill is at fault, if for arguments sake the drill is used mainly on steel or worse cast iron the cutting edge Dia. can be smaller than the flutes through wear, therefor exacerbating the problem of grab. I agree with comment 3 pages ago learn to flat bottom a drill, it will stay size as the previously drilled hole will act as a drill guide, it is also very cost effective.This method was, and maybe still is widely used in industry. a fixture with a bush to support the drill which if large would have a thinned point, followed by a flat bottom drill. You realy do need this skill otherwise how will you produce a falt bottom on a very deep hole, without special and very expensive tooling. I'll shut up now as I tend to waffle on.