I think the Haenal 28 R uses ball rather than pellets. I was shown one recently and the owner said that you pour the ball into the receiver and then push in the magazine which then fills up. I think it may jam if pellets are used.
There is virtually only one pellet that works well and cycles my Haenel 28-R in 22. I bought a old tin of Hy-Score pellets probably from the 1950's? See below. They say made in England, they are fairly short with a stout tail which keeps it from deforming in the cycling. Below are more pics. Ironically this seems to be my most accurate Haenel and is in a condition I don't mind shooting it allot. Thought if I knew the English brand I would have two place to look.
https://imgur.com/gallery/w4rQF
https://imgur.com/gallery/3Cbx8
I think the Haenal 28 R uses ball rather than pellets. I was shown one recently and the owner said that you pour the ball into the receiver and then push in the magazine which then fills up. I think it may jam if pellets are used.
http://www.airgunbbs.com/showthread....ore-pellet-tin
There may be some leads in this thread.
If you can get them, try Marksman. A simple, short, rather snub-nosed traditional British pellet.
Yes round balls work well but you need them slightly larger than the caliber on these old guns. I can do that on my .177 caliber Haenel 28-Rs because H&N makes a .454 ball (yikes, right now it looks discontinued!). In 22 Gamo is the only round ball I can find and it rolls right out the barrel. The gun I think was originally meant to fire the shorter stouter pellets of its day. In all the period advertisement it never mentions balls.
The old Hy-Score Pellets work quite well and are more accurate probably than round balls.
Reading another thread here I bet these early ones were Wasps. A little larger than normal why they work in the Haenel?