Hello again
firstly to answer your question to me, its been a long time since ive seen the match rifle but from memory they were only made for three years (66-70), ive had the one i think i have for over twenty years and yes its definitly 5.4mm and you can only use ball ammo in it. It is the same as the one for sale in the previous post which someone showed, in fact all three for sale above have the rotary breech of which i speak when i say you must use ball ammo, there is also a model which i think i may no longer have which has a pivoting breech or twist to the side which when open would allow a sized pellet to be placed directly into the bore and would allow the method which torrens speaks of to be adopted.
Furthermore you will notice that protek have sold the 5.4 ammo they had for sale as it says SOLD so it must have been some they aquired rather than being correct in saying they sell it, i dont think they do as a rule, and lastly regardless of how you pump the gun they will dispatch a rabbit, ones ive had were quite powerful and discharge with a good crack, sinking a lead ball a good way into pine board, im not saying they are a 12lbs/ft gun but they are definitly more than that which has been suggested, you could also get a ball mould made so you can make your own ammo, but you would need a melting pot and the shot would be best tumbled afterwards so again it wouldnt be cheap but its not impossible if you are adamant you need an excellentgevaret, and by the way unless im mistaken the AB just means that its a swedish registered company or something like that.
Ric