Taipan veteran puff of air from breach area when shooting

Check out the breech seal. The barrel screws into a block. on the other side of that block you see a brass ring. Not even 1/16" in you should see a good oring. If it is damaged or just plain missing you will get that puff. Some outfits that sell seals sell picks that are safe(soft). A toothpick might work ok to peel it out. once its gone fiddle the new one in to place. Hopefully your rig came with seals. If not do a search and you will come up with a list of them for this rifle. I believe what I am describing is called a breech seal. Happy hunting