You either use lead wire or cast a lead core. I use this adjustable core mold to cast lead cores for the 22cal & 30cal jacketed bullets.
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I also have a 8-cavity mold that rains lead cores for the 223rem's. Cast 1300 cores in less then an hour with it.
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There's 2 ways to swage jacketed bullets, 1 way for blammo ammo & the other for surprisingly accurate bullets.
Blammo ammo:
Drop cast lead core into a jacket like what the op has in his picture.
seat core/flatten out in jacket with seating die.
Point form the bullet, clean the lube off and use.
Quality bullets:
Use either cast cores or cores cut from lead wire and lube/run them up in a bleed die to uniform the size/weight.
Clean core put in a jacket and use a seating die to flatten the core in the jacket. This will also expand the jacket 1/1000".
Lube the expanded core jacket and run it up in a point forming die, clean and use.
I don't make 30cal swaged bullets anymore but I still do several 1000's of the 22cal's a year.
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