Always considered the BM, BKS etc to be pretty nice quality. From your observations, they seem to be spot-hardened which is better than not hardened at all. The safety seems to cam the hammer out of contact with the sear and to be pretty positive. These, or most of them have non-inertia full lenght firing pins and shouldn't be dry fired. I shot one several years ago and found it functional with the loads I had - probably ball but don't remember.
Useful report on your part as your observations always are. Noted your shooting with a 1911 a week or two ago - most competent trigger work and good clarity of reporting.
here recently, milesfortis.com decided I needed my own web address and here it is.
http://www.milesfortis.com/mcump/mc11.htm
down at the bottom is a deal on the 1911 which is always a risky subject to write on as it brings out the nut experts. Think you might enjoy it though.
mc