Thanks to you all for your replies!
The title was a bit of a clickbait — sorry about that!

This obviously isn’t a huge issue, and I know I might be nitpicking here —
but that’s only because I genuinely like the sight picture and was impressed by how feature-rich the sight system is. With the interchangeable front sight, rotary rear notch, and positive click adjustments — and coming from Weihrauch — I just expected it to feel a bit more mechanically solid.
That said, it’s good to know this isn’t just an issue with my rifle, and that many of you are totally fine with it.
Peep sights and scopes are great, but I also really enjoy shooting with open sights — not just because they add a bit of extra challenge, but also because they were the first type of sights I used when I was a kid.
As for how much this play actually matters — I agree it’s not a huge deal, but I don’t think it’s completely negligible either, if you’re serious about shooting with opens. In my case, there are three areas where play is present, creating around
0.2–0.3 mm of total movement (though it’s hard to measure precisely). To put it into perspective, the amount of play is roughly equivalent to two or three clicks of windage adjustment on the rear sight. These parts may “reset” to a relatively consistent position after each shot, but it’s hard to verify how consistently or to what extent that actually happens.
Given the HW30s’s sight radius of 39 cm, a 0.2 mm shift at the rear sight translates to roughly
1.8 MOA of potential point of impact shift. That’s not catastrophic, but still significant if you’re trying to squeeze the most out of open sights.
For example, here’s what I got with a rimfire — about 1-inch groups at 50 yards, which is about
2 MOA. A possible 1.8 MOA sight shift would noticeably open up a group like that.
View attachment 554262 For reference, the rifle was a CZ 457 Lux, which is known for its accuracy and comes with nice iron sights. Interestingly, it doesn’t have interchangeable front sights or a rotary rear notch like the HW, which is why I feel pity that the weihrauch sights are so awesome but having the play.
Of course, if you’re not particularly into open sights, or not too focused on squeezing the last bit of precision out of them — that’s totally fine too! I get that most people scope these rifles anyway, and this level of detail might not matter at all in regular use.