i've often used a TUBING CUTTER( plumbers section) to extract decapping pins /rods from cases- a case is nothing more than a brass tube anyway- it's a whole lot faster than the hacksaw- basically it goes like this- you get a stuck case- take off all the nuts and crap holding the decapping pin/rod to the die- then either put the die in a single stage press or vise to hold it steady- then hit the decapping rod with a hammer- it'll mush if you use a steel one, then you have to rethread the end- once the case pops free of the die, then cut the case with the tubing cutter- you tighten the handle EACH TIME you make a reveloution to get it to cut- do it in the middle so the brass isn't as hard as on the head-when you get through, the top of the case simply falls off the decapper , as you've already past the neck- then re-assemble your die , set it up like the first time, and you're good to go