HBWC and Pyrodex?

[Shotgun Willy]

I've got an old Iver Johnson in 38 S&W, that I reload for. It's a 3rd model but because of its age and being a top break, I use Pyrodex RS in my reloads.
Anyhow, it doesn't shoot too bad with 148 gr. wadcutters, loaded as if it were a regular round nose bullet, but I'm thinking some HBWC's would really be better for accuracy.
My question is, when loading HBWC's on top of black powder or a sub, do you need to do anything special to avoid an air pocket? Or does the powder just shift around and move up into the void?

Thanks
Bill

 

[noelf2]

Remember you have to compress black powder and most subs. When you compress the HWBC on the powder, the powder will compress up into the skirt of the bullet. You don't have to do anything special.

 

[Shotgun Willy]

Thanks

Thanks, I was thinking the powder would "flow" up into the cavity, but wanted to ask first.