Question on Trap Door set trigger.

[Reg]

Posted this question on another site and not getting much in response.
Have a Gemmer style Trap Door am thinking about taking deer hunting. Was trying various loads today and came to the conclusion the trigger pull is way out of hand, I won't even try a guess where it is.
Even if I don't get it done in time for this year would like to see about taming that trigger and making it a lot lighter either by working with or modifying what is there or replacing it altogether with a set or double set type trigger.
Anyone have any experience with this ?? There are a lot of Trap Doors out there and surely some one has come up with a cure.
Thanks
Reg

[M-Tecs]

Some options

http://castboolits.gunloads.com/showthread.php?48141-Wanted-Diagram-pictures-of-Trapdoor-single-set-trigger

http://trapdoorspringfield.blogspot.com/2012/12/trapdoor-trigger-pull.html

http://therifleshoppe.com/catalog_pages/us_arms/(533).htm

http://www.trapdoorcollector.com/cgi-bin/afrasca/bulletin/config.pl?read=25316

http://www.trapdoorcollector.com/TDNews.html

[fouronesix]

I assume your Trapdoor has an original lock. The TD lock is just like its predecessor musket locks- very simple and straightforward. Simple trigger with bar that contacts sear which engages in notches in the tumbler. If you are uncomfortable working on triggers, sears, etc. probably be best to get it to someone who knows how to do it right. They can easily be made unsafe. I've done both of my Trapdoors' triggers and now they break smoothly at about 5#. I don't think there would be much advantage in going to a set trigger. That may involve other problems and the Trapdoor tumbler doesn't have a fly…. which is usually associated with the use of set triggers.

[Reg]

Some options

http://castboolits.gunloads.com/showthread.php?48141-Wanted-Diagram-pictures-of-Trapdoor-single-set-trigger

http://trapdoorspringfield.blogspot.com/2012/12/trapdoor-trigger-pull.html

http://therifleshoppe.com/catalog_pages/us_arms/(533).htm

http://www.trapdoorcollector.com/cgi-bin/afrasca/bulletin/config.pl?read=25316

http://www.trapdoorcollector.com/TDNews.html

Thank you, this is exactly what I have been looking for. Think for now I will stay away from going to a set trigger but rather just try to lighten up what is already there. Lighten a spring and put in a travel limiter might just do the trick. Not trying to make a bench gun out of it but just want to get rid of a trigger pull that must be between 20 and 50 pounds !!
I do thank you
Reg

[KCSO]

I took my standard trapdoor down to a safe 3.5 pound trigger pull with no problem. It does require careful work.

[fouronesix]

20-50#, mercy that's heavy! There is a good chance the sear spring is not the culprit unless it's contact end is too long. It's contact end can be polished along with it's bearing surface on the sear. I'd try that first before lightening the sear spring. I think the main spring on these should be left alone.

It could be that the angle between the sear and the full cock notch is too negative, meaning the sear is being captured by the angle between the sear and notch. Correcting that is the tricky part and can cause problems if not done right.

To reduce sear engagement (if that's what you're referring to), a thin shim "spacer" can be soldered onto the tumbler under the sear just to the rear of the full cock notch. Then honed down for desired sear/notch engagement.

[Reg]

20-50#, mercy that's heavy! There is a good chance the sear spring is not the culprit unless it's contact end is too long. It's contact end can be polished along with it's bearing surface on the sear. I'd try that first before lightening the sear spring. I think the main spring on these should be left alone.

It could be that the angle between the sear and the full cock notch is too negative, meaning the sear is being captured by the angle between the sear and notch. Correcting that is the tricky part and can cause problems if not done right.

To reduce sear engagement (if that's what you're referring to), a thin shim "spacer" can be soldered onto the tumbler under the sear just to the rear of the full cock notch. Then honed down for desired sear/notch engagement.

Well, I might be stretching things a bit with that 20 to 50 pounds but it sure does feel very heavy. One of those things you concentrate and start your squeeze and the squeeze never seems to end.
Think I will start by very slowly reducing the sides of the sear spring and see what happens. I like your idea of soldering the shim to the tumbler. Was thinking of trying to either drill for a pin or drill and tap for a adjustable screw to control the engagement but am betting that part is going to be glass hard deeper that one thinks. Soldering should not disturb the heat treatment and should accomplish the same thing. Good idea !!

[fouronesix]

Yes, a very heavy trigger can test the best of anyone's concentration even on their best day :).

With my '84 TD using the Buffington's rear peep at lowest setting and a taller blade front, I could "usually" shoot 3/4"-1" groups @ 50 yards. Once in a great while, if my trigger concentration was good that day, I could best 3/4" @ 50 yards.

After re-working the trigger on this rifle (reduced from about 10#+ to about 5#) I can now usually shoot groups in the 1/2"-3/4" @ 50 yards.

Here's a .63" 6 shot group @ 50 yards from last week with the '84 TD. I scavenge decent black bull targets out of the trash at the range so disregard the other 30 cal? holes.