That's a new one on me. I've never seen a bullet that you thread the ram rod into. Maybe I'm out of touch or something.
I use Power Belts. You just slide them in with your rod like good sex. After about the 3rd round, the sex starts getting dirtier and it get's harder to knock the bottom out of it. When it starts to get hard to push, I use my ball starter which has a hole counter sunk into 1 side of it that I put the end of my rod into and use this against the palm of my hand and use that to push it home. If you have that, cut a small block of wood about the size of the palm of your hand and drill a 1/2" hole in one side about a 1/2" deep to set the rod in. After about the seventh round, the sex is so dirty, that you have to make her douche that thing out.