scout34,
The setup on the left of my photos is for the 357 Magnum. Years ago, the hollow pointer was specific for cartridge, i.e., 38 Special or 357 Magnum and I suppose, 357 Maximum would work in the one indicated. The one on the right is what is offered now and it is to be “universal”. Well, I guess it is as the sleeve is tapered in the inside and it will center whatever bullet is place again the interior. The drill bit helps align it to center as the collet that holds the loaded round is tightened.
Both of these types are extremely labor intensive and quite slow. I use them for specialty rounds only. I have had the 357 Magnum one for a good many years and yes, the hollow pointer does help to start the cast bullet to expand on impact. I have tested a good many shooting into catalogs and expansion is fair. I was only using wheel weights as the alloy back then.
I purchased the “universal” one to test 44 Magnum cast slugs. (I was hoping they had the old style hollow pointer, but it is discontinued.) I am using it with the RCBS 44-250-K bullet—a Keith style slug. These bullets are cast from pure lead, so I am hoping for good expansion—we shall see as the weather improves a bit.
One bit of information—the Forster case trimmer has different length bases. I have all 3 lengths. I think you need the middle length or possible the longest length to have enough distance between the collet and the drill bit. I had the longest on in place so that is why I used it. The short one won’t work. So, all of this can get expensive if you haven’t previously acquired the case trimmer for its intended purpose. I have had mine for dozens of years, so an accessory is just a bit of upgrade.
I would be surprised if you can keep the drill bit centered without some type of support. I am not real familiar with the RCBS case trimmer, but maybe it is better equipped to do this rather than the Forster.
Maybe as I try a few of the slugs for expansion, I can post some pictures in the future. Good-luck…BCB