Unless I'm very much mistaken (
) Sportsmatch do 30mm adjustables, and these come
highly recommended. If you have a problem getting the product number, let me know and I will ring them.
Funny you should mention the HW100.
Do not lap your ring mounts. Great idea, but ... No, thinking about it, useless idea. This procedure will allow you to line up the scope tube through the rings if they are misaligned, but a one piece adustable from Sportsmatch won't need this.
IIRC they released a two piece version 3-4 months ago. But a HW100 should have a one piece.
Lapping a 25 or 30mm ring will make it larger. Lapping a mis-aligned ring will make it eccentric (oval). Use Burris Signature rings if you have to, but don't lap your air gun mounts.
Remember:
If the gods wanted you to lap your rings, They would have supplied a 1" or 30mm ground bar with every set of rings, and a side order of grinding paste.
Sportsmatch are the best ring/mount manufacturer (for airgun) bar none. I doubt they would design anything that didn't work. Don't worry about adjustables not working. You've nothing to lose by trying. If they lose zero on your rifle, you get your money back. Simple, eh?