double set trigger setup

[twig]

On my 36 caliber i am having difficulty fine tuneing my double set trigger. When I get it down to the poundage I i would like to have it seems to have too much pressure on sear bar and the lock won't lock in full cock positon.
Can I bed the sear bar with heat? It appears it is heat treated.
Should I just pull the trigger and file the sear down till it doesen't put pressure on the sear bar of the lock? btw it is a davis double set trigger
Thanks in advance for the help

 

[MSW]

I'd be hesitant to bend the bar, but that's just me ... if you decide to file away at the sear, you may want to consider having a replacement part in case things go very wrong very fast ...

(don't ask me I how I know) :redface:

(mutter mutter mutter ... something about wisdom comes from experience ... so how come I'm not the smartest guy in the county?)

 

[don hepler]

The full cock position is part of the lock operation and should not be part of the trigger adjustment, unless the sear bar is touching the trigger arm. If this is the case shim the trigger down. Sometimes the wood gets compressed and lets the trigger push closer to the sear bar. I have a shim in one of mine. I was going to put some bedding in, but shim works fine, so I'll just leave it. A little shim is worth a try.

 

[hpdrifter]

On a DSDT trigger, when setting the triggers, the front trigger has to move up marginally. Also, the lower the poundage or more sensitive, the higher the trigger bar will be.

You will have to lower the front trigger some, either shim or file. You will have just a hair of slack for using the front trigger alone.

 

[twig]

spare triggers...Check don't ask how that occured has to do with torch, hammer and vice....decided to use my 18 yrs of blacksmithing experiecne to work :cursing:
It looks like either 1mm shim on trigger or take 1mm off of the sear of trigger.
The next gun will have a single trigger of my making A single trigger in the right postion will give me like 2lb pull i think after looking things over.
Thanks for the advice guys ....Kinda what I had resolved to do whilst thinking on the subject when cutting fire wood this afternoon

 

[LRB]

If you put a thin washer under the rear triggers spring, you create a wider gap, more free play, where the trigger arm strikes the sear arm. This also will lighten the pull weight which may or may not agree with you. Worth a try with nothing lost, but it may also not provide enough strike power to trip the sear in which case work on the tumbler and sear may be required. With some triggers, just backing out the springs screw a tad is enough.

 

[ApprenticeBuilder]

Another option,

I have drilled and tapped the trigger bar for a 5-40 screw and used it in the manner of an over travel screw for the trigger main spring, once completed the screw can be filed flush with the visible side of the trigger plate.

Doing this allows for setting as much tension as needed on the triggers with the main spring but stops the full downwaed travel of the spring allowing the lock to be placed in full cock without setting the set trigger first.

No need for shims that may place the trigger plate proud of the finished wood.

Hope that makes some sense.

 

[LRB]

Another way of getting the same result, and a better one. I have seen DST's with that screw, but the washer is something anyone can take care of easily, quickly, and remove if it doesn't help their problem. If a thin washer under the spring interferes with seating the trigg assembly, the inletting clearance may be a bit too shallow to begin with. IMO.

 

[Pete G]

Try filing the tip of the kickoff spring until the rear trigger extension is clear of the sear. If you have a recent TOW catalog they have a good explanation of this method, along with helpful illustrations.

 

[LRB]

Another simple fix that can also work, but is a permanent modification that cannot be easily undone if ever needed or desired, without the purchase of a new spring.

 

[Birddog6]

IF you bend the sear arm, put the sear part in a vice & heat with a small tipped torch, heat the arm in one spot & bend the entire arm up just a tad. Do not tip or cant the arm part that rides against the triggerbar.

Have a cup of motor oil beside you & when you get the part heated & bent, grab it with pliers & drop it in the oil & let it cool. Keep in mind to bend it SLIGHTLY, as it sometimes only takes 1/32" or so.

But the idea of putting the washer in under the triggerplate works best & will tell you of the triggerbar is too tall. If so, then you can work a remedy from that.
Normally it is the other way around, you can't reach the sear arm, or the front trigger is too hard to pull.

Takes some time & diligence to get them right, but I usually end up with 3-4# front trigger & set trigger working correctly as well.

Keith Lisle

 

[hpdrifter]

Don't really need the copy of TOW catalog. There is an online pdf file for it.

Google set trigger adjustment or page_352.pdf

Link

 

[twig]

Thanks to all for the advice. I did not know that tow had this pdf! I guess tomorrow I will pull the trigger off and do a correct adjustment. I would like to get a nice light pull. I will see how that works :wink:

 

[don hepler]

Thanks for the link, some handy information to have.

 

[hpdrifter]

Just a word of caution. I think they got the leverage for the front trigger pull backwards. The closer you get the sear engagement, the more leverage you'll have(easier pull) but will have more travel(creep) so a balancing act there.

Unless, I have their forward and reverse misunderstood.