Single Trigger Sear Engagement

[David Rase]

I acquired a Dunlap Isaac Haines kit a couple of weekends ago.  I have all the hardware installed except the trigger.  With the trigger guard installed into its pre-inletted spot on the stock and the trigger pivot at 1/4" the trigger ends up being way far to the rear of the guard bow.  Normally I pin a simple trigger about 1/4" in front of the sear to obtain a trigger pull that I like.  My question is, how far forward have some of you pinned a single trigger and still had a good trigger pull?  I want to pin the trigger as far forward as I can to get the trigger positioned to where it looks good in the guard but do not want to sacrifice trigger pull.  I am fairly comfortable that I could go to 3/8" but wondered if 1/2" would start to get to heavy.  Thanks for your input.
DMR

[smallpatch]

David,

I've had the same problem with a Dunlap kit.  If you get it as high as possible, it should still be all right.

Conversely, you usually have plenty of trigger blade at the rear, you could always "notch" (cut the front of the blade off, thus providing an offset) the front of the blade, and move it forward a little, thus moving the pin closer to the sear, and moving the trigger a little forward in the guard.

Does that make sense??

[Don Getz]

Dave.....can I assume you are working with the same trigger that you got with the kit?   We originally designed the kit
around a trigger that Davis sells, and is pinned thru two bumps that rise above the plate......never really liked it and
could never really get a great trigger pull with them.  If I were doing it, I would inlet a straight trigger plate, one that is
big enough to cover that inlet, then use a single trigger pinned thru the wood.   I know you can get a light trigger pull
with only 1/4" distance from the pin to the sear, but, don't you get quite a bit of trigger movement when you go that
short?   I ususally try for about 3/8", found that it seems to work well.......no matter which way you go, you still have to
do some stoning on the sear surfaces in order to get a good pull.............Don

[David Rase]

Don,  I went down the path you just described.  The trigger that comes with the kit was too narrow for the inlet so I made my own trigger plate that fit the inlet.  I then made my own trigger.  You are correct about the terrible pull you get when you pin a trigger low and to the trigger plate.  I plan on pinning it high in the stock between the sear bar and sear pivot, like I do when I build from a plank.  Going to 3/8" will help a lot.  I was just curious about the pull.  It sounds like 3/8" will be just fine.
DMR

[David Rase]

Dane,  I had to think about what you said overnight but the light finally came on about 6:00 AM this morning.  I think between changing the trigger pivot to 1/4" to 3/8" as Don suggested and then notching the front of the trigger blade to move it farther forward in the trigger slot another 1/8" the trigger will be right where I want it and still have a good trigger pull.  The triggers on the Bivin's style guns I have seen slope to the rear quite a bit so that will place the point where the trigger finger contacts the trigger pretty much right under the pivot.  Excellent!  I can't wait to get home from work tonight and put these ideas to work.
DMR

[Dphariss]

I acquired a Dunlap Isaac Haines kit a couple of weekends ago.  I have all the hardware installed except the trigger.  With the trigger guard installed into its pre-inletted spot on the stock and the trigger pivot at 1/4" the trigger ends up being way far to the rear of the guard bow.  Normally I pin a simple trigger about 1/4" in front of the sear to obtain a trigger pull that I like.  My question is, how far forward have some of you pinned a single trigger and still had a good trigger pull?  I want to pin the trigger as far forward as I can to get the trigger positioned to where it looks good in the guard but do not want to sacrifice trigger pull.  I am fairly comfortable that I could go to 3/8" but wondered if 1/2" would start to get to heavy.  Thanks for your input.
DMR

If the lock is done right 1/2" to 5/8" is not going to ruin the trigger pull. You might find you like it if the lock is properly adjusted. I once had a single trigger Sharps match rifle with a trigger under 1 pound and it has a pretty good distance to the sear. It would also pass my "mallet" test without dropping the hammer.
My 16 bore has a long reach, longer than I wanted and is OK as well. Very shootable but a little heavy for a match rifle but as a hunting rifle its fine.
The longer reach will produce a crisper pull in most cases.  I have a pistol in processing right now with the trigger pinned at the location of the sear screw on an L&R Manton it has a trigger pull just under 2 pounds.
But its an English dueler style with a rather long trigger compared to some Kentuckys.
I don't like triggers pinned close to the sear, requires too much movement of the trigger.

Dan

[Stophel]

I put my pins at 1/2" from the sear arm.  I tried 3/8" once.  Will NEVER do it again.  Oh, it was light, but insanely L-O-N-G.  Very disconcerting.  The weight of the trigger pull is governed FAR more by the weight of the sear spring (and the angles on the sear nose and tumbler), than it is by the distance of the pivot pin.  That distance, however, has a great deal to do with the length of the draw required to let off the sear.  The closer it is, the longer you will have to pull the trigger.  The farther away, the shorter.

So far, of the few old guns I have been able to take apart, every one of them has the pin at least 5/8" from the sear.  Usually, it seems to be about 3/4".

And their sear springs are massive...

[Don Getz]

Whatever works for you...............Don