…as a result we have the next story:

Actually every custom gunmaker produce left swinging top lever but many lefties that work for gunmakers use right swinging top lever in left hand guns and even left swinging in right hand guns.

Actually there are a lot of thoughts about advantage of right lever opening in lefty’s gun.

Faster handling – you do not need to change your grip while you are opening the gun (actually I did not notice it until I tried to open right hand double with right hand)

More reliable opening - you can apply more effort by pushing over pulling the top lever in the situation where locking system is polluted or a little damaged (of course it doesn’t happen often and I doubt it ever will take place but if it ever will happen this will not caused a problem)

Comfort of handling, to all appearances, it’s a matter of habit – it’s not an advantage of right or left lever opening - at worse, and right lever opening is even more comfortable for left-handed guns - at best.

And ladies and gentleman there is the main question – why 99% of right-handed guns have right lever opening?

P.S. 99% because some people find left swinging top lever like more comfortable in right-handed guns in use ( for example Kevin Kilday from Westley Richards).