I think I remember this topic being discussed here before but couldn't find it via forum search.

I had my 1895GS out today for the first time in 3 weeks...had wisdom teeth on right side pulled 2 weeks ago.  I picked up where I left off working up two loads.  Both of these are near max:  1) 300 gr Rem JHP + CCI200 + Starline + 59.5gr H322  2) 405 gr Rem JSP + CCI200 + Starline + 50.0 gr Re7.  From the beginning I noticed that the lever had a tendency to pop open on most shots...but not all.  My buddy and I talked about this for a while and came to the conclusion that this was probably due to the rifle recoiling against the lever hand.  I didn't notice any obvious signs of high pressure.  The cases are in the tumbler right now and decapping might tell another story.

Didn't someone here bring this same topic up once before?  Has anyone else experienced this?

BTW, I am REAL happy with this rifle.  It is easily the most accurate levergun I own.  Those 405's are the best.  My eyes aren't good enough with peep sights to group real tight on paper but busting rocks on a distant hillside is too easy.  This kind of shooting is the best practice for hunting (IMO), and we do it a lot.

Bart:

Is the lever popping open when firing from a rest or offhand or both?

I have a heavy recoiling 44 Mag that does the same thing when firing off a sandbag Camp Perry style since I don't have as tight a grip on grip and lever. In my case the lever opening a bit is normal, albeit painful when the rifle jumps and the trigger jabs my forefinger.

hi from Germany
The same thing happens to me with both my mod. 1895SS and 444SS rifles , but only on the range when I´m shooting from a rest. I think it`s due to recoil and lack of firm grip on the lever in this almost prone position . So don`t worry about that.
Happy hunting!

I think this is probably akin to "forearm unlocking" in a pump gun shot from the bench.  As described by Jim Carmichel in his "Book of the Rifle" (great book), the forearm on the pump gun is (unlocked) dragged across the bags as the shooter recovers from recoil.  It gives the appearance of coming unlocked at the shot, but of course this is not the case. If it did unlock at the shot, the shooter would be very aware!  Spewing gases and bits of brass and all.