expander ?

who makes or where can I by a powder through expander for the Remington 148 gr hbwc's .360 bullets ?

Lee will make custom expanders for their powder through dies. You give them the measurements, send a couple sample bullets, with $30 and they make one. I don't know for sure, but would guess other die manufacturers do the same.

Thanks for the info

If you use Dillon press, contact Steve Bathje at sbathje@yahoo.com. I emailed him a few days ago, he said he will be making custom .38 expanders for Dillon powder measure. Let him know that you are interested too and tell him you need one for .360 bullet. I'm not sure if these expanders will work in other dies.

Thank you I just send him an email as you suggested. Thanks for the address I asked him about one for a Hornady LNL AP