I dont think that is the way lead wire is made. I dont know though. I do know how steel,stainless, and copper wire is made. It is not by pushing through a die. You keep reduceing down to near the size you want and then it is rolled in a set of 4 dies each turned in 1/4 positions. Lead would be much easier to work with because it could be run cold. Alloy wire is very hard and must be run hot and very very fast. I have seen the wire break before it hits the coiler and a 1/2in dia piece of wire will shoot through a 1in steel plate.
If i were going to try the pressing thing. I pour in something that would make it close to the size you want to press to. A good mold could be made out of cement or fire mortor. 2 halfs and rod or pipe to make the chanel. shotman