B3 Pellet Rifle Breech Seal

Printable breech seal for your old B3 pellet rifle.
I have a .177, though the I.D. should be good for use in .22 also.
Creates a much better seal than the 25+ year old original one I had in my B3.
Created in TinkerCad with measurements using Mitutoyo digital caliper from replacement breech seals I originally ordered from eBay.
The orange one on the left is my original, white in the center is one I purchased from eBay (supposedly OEM) and black on the right is one I printed.
Print in TPU.