You need more than a trigger alone.  You will need a hammer with a fly and a sear with a groove in it where the fly rides.  Or you can grind off the 1/2 cock notch.  You can install the lower tang parts in your existing one.  You need a set trigger, trigger catch, trigger catch spring and a stiffer knockoff spring.  I have installed the MVA parts in a couple of walls with little modification.  One needed the trigger sanded to slightly reduce its width to move freely and the hole for the catch spring was not deep enough for the provided spring.  I could have easily deepened the hole, but I had a shorter spring that works fine.  The MVA hammers they sell have a provision for a fly.  They sell a fly and pin as separate items.  The hammer is correct for a low wall, but short for a high wall but will work OK, just doesn't look right. 
I just ordered a couple of set triggers last week.  My Winder musket came with a fly in the hammer and a correct sear, so I figure I might as well install the rest of the parts.

Jack

CW wrote on May 6^th, 2024 at 12:43pm:


The biggest issue I had was the knockoff springs. They are the hardest and touchiest part of the single set trigger and those from MVA and as well as C Sharps, never seem to be quite right and needed a lot of tweaking just to get them to work. I wish the original Ballard Rifle company in Cody was still around and we're making parts for the high wall. I put three sets of their wide spaced double set triggers in my rifles and they were almost near perfect. It's much easier to shoot the offhand when you can have the rifle in position and then just set the back trigger and you're ready to shoot. Much easier than having the rifle in the down position setting the trigger and then bringing it up to your shoulder and shooting. I have not had a set of MVA wide space triggers and can't speak for their quality but I would assume it's pretty good from their other stuff I've seen.

Great info provided. Thanks!!!

About a month ago I called MVA. They helped me put together a list of parts needed to convert my single trigger rifles but of course they could not offer advice or trouble shooting on my specific rifles so your input is very helpful. Thanks again.

I have had a few calls into MVA this week to order parts and no return call back yet.  Hopefully they are too busy on machines making parts to call back. Maybe next week.

That could be a good plan for the low wall. Dan did the barrel for me. He may have even asked me if I wanted a ss trigger at that time, can't remember. The high wall I am going to try to do here and soon.

thanks!

even better use the purple loctite witch is made just for this