BPCR question with Hollow Base cast

[Old Time Hunter]

Need the eexpertise of all you BP cartridge loaders.

Situation: Casting using a Lee 459 405HB mould, the bullets dropped at .4615 nominal (+/- .001) and weigh 425 grains. I do not plan on sizing intitially since I will be loading them for both original Trapdoors and a Sharps '77. The Trapdoors (9) slug anywhere from .460 to .462, while the Sharps slugs at .4595. My question is, whith the hollow base bullet, do I still need a wad?

By the way, I will probably start at 60 grains of cartridge BP.

Another question, my recent BP loads with 70 grains BP, .030 veggie wad, 405gr flat based LFN's, have started to balloon my shells just before the rim. What could be causing that? I can still resize 'em without cracking, should I still use 'em?

[Chuck 100 yd]

Old Time Hunter, As I understand it, and I have fired many HB bullets in ML rifles, they are ment for low pressure loads.
I have seen pictures of HB bullets that have the base flaired out like a Badmitten shuttlecock (sp) from too much pressure. The old time shooter Dr. Mann did some extensive tests and soft solid base bullets would do the same thing when pushed hard with black powder in short barrels.
I think testing in your rifle is the only way to tell for sure. I dont think a wad is needed for low pressure HB loads.
I shoot 60-65 gr. 2FF in my .58 cal. mushets with the 635 gr. HB minnies.
The skirts on those very soft bullets expand very easily and origionally were filled with lube.
Have fun!

[Ben_Rumson]

Another question, my recent BP loads with 70 grains BP, .030 veggie wad, 405gr flat based LFN's, have started to balloon my shells just before the rim. What could be causing that? I can still resize 'em without cracking, should I still use 'em?

I'd say you have finally got the pressure up enough to fully expand the case..Also if you have recently annealed your cases then the soft brass is not springing back like it would have before you annealed them...