Hi All,
I don't remember seeing anyone else post on these so I figured that I'd share what I was doing on building out two of these 1878 Sharps Borchardt DST kits as supplied by our good friend Rodney Storie. Most of the parts are water-jetted from appropriate steels.

I had help from several friends - including drawings and a completed / operational DST on loan from Amoretti - Many THANKS John! Been trying to push myself to get mine done so I can send his back.
Also wanted to thank Joe D. for some great pictures of his original AO Zischang Borchardts and triggers. These were VERY helpful in milling/filing/sculpting out the little nubs in the spines on the backs of the triggers. There was just enough metal in the water-jetted trigger parts for these Zischang details.

Getting the Cart before the horse now as they say... Sharing some pics of where things are now. Most of the machining is done and the set triggers function nicely. I have just mostly finished polishing out the two trigger sets and they're now both ready for the kickers and associated machining...

VERY nicely done. Thank you for posting. 

This is a good picture of the triggers underway...
Marked out the locations for the pins - different between front and rear. Then drilled and reamed each. I went with O-1 I had on hand for the pins. You can see the triggers in their as supplied shapes - VERY NICELY water-jetted! And also the first rear trigger with the top milled to fit the .135" slot. This will get further milled lower as we move along.

The biggest challenge at this point for me was - HOW TO HOLD THE TRIGGERS?!?!
I figured I could make up a vise jaw and what you see is what I came up with and worked well. Two pins of correct size for the front and rear triggers and an adjustable screw to support the first side while milling the second face. Trigger is held in position by the vise jaws and secured by the pin from moving while milling. Worked well!!

I located the fixture pin for the rear trigger so that the top of the part could be skim cut just a few thou as needed as can be seen in the picture. Note the use of another trigger (on left side) when clamping the fixture in the vise to provide support to keep the jaws parallel.

NICE jhm!
I also have a couple of Rodney's Borchardt kits in the works. Needing to get back to those. One receiver is threaded and the breechblock mortise done.
JP

Thanks GT,
Slowly digging out from all the home projects and hunting season is now upon us! Got out to do some shooting yesterday with my son and his friend. Shot the Borchardt in .50-90SS and the vintage 1895 Marlin square-bolt in .40-82 - quite the sweetheart!

Moving along on milling the front triggers...
Added a second pin to the fixture to the right and below the support screw, for the front trigger. IIRC the drawings show the front to rear trigger pins separation as 1.000". I chose to make mine closer after some measurements/trials. You get to determine this now and drill/ream where you think will work best for the parts you have. That was my reasoning for installing the rear trigger first. After this I marked where I needed to lengthen the slot on the front end and did so.

Some fitting was needed for each so they would mesh correctly... then they were ready for the rear spring to power these. I was luck in that I had a sample from John to work from. I used a deadblow hammer over a 1.5" round bar, pinching the spring blank (anchor end) in the vise between the vise jaw and the round bar. Carefully forming it to the same shape with the deadblow hammer.

Heat-treat was done with MAPP gas until non-magnetic then quenched in oil (ATF). I tried to draw these in my leadpot but didn't get them hot enough - no fear, I just switched to the vegetable oil in a can method and that got them done. After cleanup and a good polishing, I drilled and tapped the plate for 10-32 screws and they worked perfectly!

Next I drilled and tapped for the front springs, which I made from some thinned (.021") steel band/strapping. I used 3-48 cap head screws. The one that holds the spring I chose to make a blind hole, the other for pressure adjustment is a through hole of course.

The bottom spring pressure adj screw needs clearance milled into the rear of the front trigger. You can choose to mill the triggers to crescent shape at this point... or just mill for some clearance to get things working. Trim the screw to good working length as well. Zischang used a large head screw that covered over and limited the travel of the rear extension of the front trigger... as seen below. This rear extension is longer than the ones as supplied in the kit so there is some difference here.

The front trigger also is notched with a .025" slitting saw at this point for the front spring as shown below. You can see the triggers at the bottom have been thinned using the fixture plate to hold them in the mill - now has a "spine" and a slim crescent finger pad. I worked to add in the classic Zischang nubs at the bottom of the spines,. There is just enough material on these (Thanks Rodney!) for this detail. Gives them a pleasing appearance IMHO.

The triggers at the top of this same picture have been shaped very carefully using a Dremel with a brown stone and then rough polished with the sanding drum. Took me about 2 hrs for one set to do this. Still more work ahead with stones and paper to finish polish them

FYI NOTE: I found the fixture plate VERY helpful in holding the triggers while filing the shapes in by hand when needed.

I have done quite a bit of fixturing over the years. One thing I learned is the simpler the better. Do just enough to hold the part secure and rigid. Your plate to hold the triggers is just that. Simple and got the job done. Do you know if Rodney has any more of these kits? Also do drawings and instructions come with them? Thanks for showing the attachment to the receiver as I was curious.



JMH

Nice work Jeff.  Thanks for showing the progress, it’s always nice to see how others do this type of work.
Bob