Almost al the RWS Dianas have barrel droop, I know my 54 has barrel droop but it is not really a problem, I read once that Diana makes it so on purpose and just found this post from earlier on the forum regarding barrel droop in a 48 sidelever:
Yes, my 48 is very droopy. February 27 2005, 9:19 PM
I was quite surprised when I discovered my 48 has lots of droop. An adjustable mount is required- at least on mine. I use the B-Square AA and it works good.
I posted a question to the Fun Supply forum about why barrels are drooped. I wrongly thought it was a mechanical reason having to do with break-barrel cocking. The answer I got was that it is popular in Europe to shoot 10 meters with peep sights. In order to shoot short distances with a peep and an upright head position, the barrel needs to point down so the rear sight can be high.
Definitely check to see what others say about their Diana side-levers, but mine is very droopy.
Hope that helps,
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