I was asked by a member about sears for a single set trigger and thought I would take some pictures and post them with what knowledge I have.  It may help somebody when buying parts.  Bob

This first picture shows the difference between a standard trigger and one machined for the trigger hook (ribbed).  The ribbed trigger has a hole in it for a spring and there is also a hook or catch that is needed to make the single set trigger functional.  The ribbing on the trigger is not necessary.  The knock-off springs correlate with the types of triggers.  Notice the difference in the curve and thickness of the knock-off springs.

This is the difference between the sear spring needed for the SST and the standard trigger.  Notice that the top one needs to be thinner so as to balance the force of the knock off spring.

The long tailed sear is needed for the CCDST and the Helm Schuetzen trigger.

These are 3 different levers that were most common for the High Wall.  I call them the standard S, the lazy S and the Helm Schuetzen.  They can go by different names besides those I gave them.  Notice how the front of the lever is ground as they were all from rifles equipped with leaf springs and not coil springs.
There were other lever shapes made by Winchester as well as by custom gunschmitts.
Please point out any mistakes I have made so that we can all learn from this post.  Good shooting.  Bob

Very nicely done and it's refreshing to see some educational information for a change.

JLouis

Are these parts available or do they have to be made?  I have a 1885 and would like to modify it to a set trigger.

John Mead

there are 4 levers for the 1885 the flat side lowalls use a liver that is a little thinner and a litttle shorter on the tang just in front of the trigger  ken

Thanks Bob 
Great photos and close ups of the parts,I learn and see things I havent seen before.

Noel