Sixtus, there is a thread here somewhere about subs with lots of useful info. I have a Rossi 44 mag break gun and shoot 300 grn at 1025 fps. It will group to 1 inch with three shots @ 100 meters.
I was siting it in at 100 mtrs but found that it was difficult to get the 'hold under' right at shorter distances - I would miss by shooting over the top.
For me having the gun dead on a 60 metres and the 22 the same is perfect. It is easy to allow a 4 inch holdover at 100 and practice with 22 & subs is directly transferable as the trajectories are the same when both are sited at 60 mtrs.
The subs work but need carful placement - Autonomic Plexus is best, tried a few aiming spots
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