Hommer, see my first post.

I have lots of experience sizing jacketed bullets DOWN and can recommend it 100%. Way easier and less troublesome than patching UP.

I have paper patched as well but it is IMO a very time-consuming activity and tho I, too, enjoy the technical end of things just for their own sake, a pain in the neck. I'd rather size down than patch. Others enjoy patching for its own sake.

Seyfried recommended rolling the jacketed bullets under a file to roughen the jackets so they would hold the patch.

Regardless, you'll need sizing dies and I can heartily recommend Lee dies. The .429 down to .423 {or whatever, slug your bore and check neck relief first} should be a snap, no problem at all and with that you can size jacketed or cast bullets. You may find for cast that .001 to .002 shoot better, so you may be into it for two dies. Order them both at the same time; $50.00, still less than 1/2 the price of a Ch4D die. Good shooting and let us know how it pans out, patched or cast!