if you ever saw a Diana model 48-52 and then you saw the Diana model 75 with the add piece in the bottom
my guess is that it helps to pick up dropped pellets
The RWS Diana 75 10-meter target rifle – Part 1 | Pyramyd Air Blog
maybe the same sort of thing, yes i looked up a picture it is just for helping you push the pellet home it looks like what would be use on a large navel gun shell push it forward then powder and push forward close breech and fire
Anschutz LG220 | Anschütz (Germany) | Vintage Airguns Gallery Forum
I could not get the loading ramp to work, so I just removed it. It seems that no other similar airgun, FWB 150, Anschutz 250, HW77, etc ever used a similar loading device? I wonder if the hole in the bottom of the stock must to to allow a dropped pellet to fall out without turning the gun over?