DST issue

[ltdann]

So I'm still having some troubles with my DST-4 triggers.

The lock will not go to half or full cock without the triggers being set.  I've put inlet black on the sear and it doesn't appear that the blades are touching the sear.  If I set the rear trigger and then cock, all is well and the lock functions correctly.

I've got the trigger plate flush to the wood and the blades centered in the middle of the sear, plenty of backlash when set.

It's my understanding that I should be able to go to half cock, full cock, with triggers set or unset and be able to fire from each trigger independently, set or unset?

I'm at a loss here.

[greybeard]

On this set of triggers that I made they were a bit too high so you can see where I had to grind the kicker trigger down a bit so the gun could be cocked without having to set the trigger.  You can also ile a bit off the toe of  the mainspring. In your case it sounds like the triggers  are  holding the sear open not allowing the gun to cock, Hope this will help a bit. Bob

[ltdann]

I think you may be right.  Something IS contacting the sear prevent the cocking.  I guess I'll tear it all down again and blacken everything to see.  I don't have much trigger blade left to file so maybe I'll try some shims.

[rich pierce]

What do you see with the lock out when you look in the sear hole?

[Dennis Glazener]

Rub some inletting black/blue on the sear bar and see 1. if its touching on the bottom of the hole in the stock inlet 2. if it rubbing up near the top where the 90 degree bend is. If so remove the wood and check to see if that fixed it.

with triggers set or unset and be able to fire from each trigger independently, set or unset?

Yep that's how it should work but it depends on positioning of the trigger/sear bar. I have had some that I never could get to fire un-set!
Dennis

[Bob Roller]

So I'm still having some troubles with my DST-4 triggers.

The lock will not go to half or full cock without the triggers being set.  I've put inlet black on the sear and it doesn't appear that the blades are touching the sear.  If I set the rear trigger and then cock, all is well and the lock functions correctly.

I've got the trigger plate flush to the wood and the blades centered in the middle of the sear, plenty of backlash when set.

It's my understanding that I should be able to go to half cock, full cock, with triggers set or unset and be able to fire from each trigger independently, set or unset?

I'm at a loss here.

The problem is obvious.IF the lock can be cocked over a set trigger and NOT over an unset one
then the release bar on the rear trigger is the culprit.The blacking or what ever detection agent
is not doing the work you need.

Bob Roller

[ltdann]

With the lock removed and the trigger installed (unset), I see part of the rear blade.  I don't believe the rear blade is contacting the sear, but I'll double check with black.

I never thought to see if the sear is riding on something  INSIDE the hole, I'll have to look.

I'm able to use it as is, but it's frustrating to be unable to go to half cock with setting the lock....it's just not right.

[okieboy]

 I am going to bet that your rear trigger is under tension even before you start to set it. Is this correct? If so then it is going to prevent your sear from engaging. If the rear trigger doesn't have slack in it when the trigger and lock are installed, then the trigger will have to be set to cock the lock; many guns are this way. Some triggers have a screw installed to limit the downward travel of the mainspring so that the rear trigger is not pressing the sear when unset.

[ltdann]

If the rear trigger doesn't have slack in it when the trigger and lock are installed, then the trigger will have to be set to cock the lock; many guns are this way.

Is it supposed to be that way?

Some triggers have a screw installed to limit the downward travel of the mainspring so that the rear trigger is not pressing the sear when unset.

I'm not following.......  Here's what I have

[D. Taylor Sapergia]

For a perfect set of double acting, double set triggers such as those, the ideal is to have the rear trigger floating when unset, just above the engagement notch of the front trigger.  That way you can have a powderful and crisp mainspring giving the rear trigger lots of powder, without the trigger's bar interfering with the sear.  If it is under the tension of the trigger's mainspring, you have your problem.

You can: 1) grind material off the top of the rear trigger's kicker bar so it doesn't interfere with the sear....
              2) tune your trigger set by filing and polishing so that the rear trigger floats as in my description above...
              3) use red heat to bend the arm of the sear first up and then out level, so that it clears the rear trigger's kicker bar...

I like #2.  This is where some have suggested that an adjustment screw be installed to take the pressure off the heel of the rear trigger.  The screw is drilled and tapped into the trigger plate just behind the rear trigger.  A #2 or #3 x 56 screw works nicely, but be advised, it is very difficult to adjust without removing the trigger guard.  So tuning is your best option.

[ltdann]

This is where some have suggested that an adjustment screw be installed to take the pressure off the heel of the rear trigger.  The screw is drilled and tapped into the trigger plate just behind the rear trigger.  A #2 or #3 x 56 screw works nicely, but be advised, it is very difficult to adjust without removing the trigger guard.  So tuning is your best option.

Like this?

[D. Taylor Sapergia]

Yup!  But you can see that that screw will be right in the bow/rail junction of your trigger guard, making it impossible to adjust without removing the guard.
You can accomplish the very same thing by filing the contact area on the heel of the rear trigger, very carefully and checking after only a few strokes, so that when you cock the rear trigger, it lifts the mainspring off the plate only at the very last instant.  That will allow you to increase the tension on the mainspring by cranking down on it's screw, and still have a rear trigger that floats.

[smallpatch]

Taylor,
TOW has a screw with a hole drilled through so you can use a vent pick or the like to adjust.  It's kinda tedious, but you can adjust it without removing the guard.

[ltdann]

alright gang, I blacked the main spring and relieved a bit of wood and I no longer have wood to metal contact on the main spring.  I loosened the main spring screw and filed the tip of the main spring.

I now can cock the lock.... but.....

the rear trigger sets itself and fires when pushed forward and I no longer have a front hair trigger.

I need to sleep on it.

[EC121]

Sounds like maybe the front trigger spring is not working.  The trigger assembly only has 4 moving parts.  Something has to be dragging or you took too much off the trigger contact area, and it doesn't have enough pressure to stand.   

[hudson]

I agree with okieboy, ran into the same or similar problem quite a few years ago. As luck would have it there was a short article with a picture in Muzzle Blast explaining the problem and the fix, it worked. With my occasional builds if the trigger assembly doesn’t have the screw I add one.

[ltdann]

Well,  I didn't take anything off the trigger contact areas, at least not deliberately.   I did have to polish the mainspring tip as I discovered some cast flashing that was hanging up on the trigger heal

I think what happened was that when I took out some more wood to relieve the pressure on trigger mainspring I messed with the backlash.

I'll tighten the mainspring screw tonight and see if I can get a happy medium.

without the hair trigger, the front trigger needs a pretty good pull to fire the lock.  All things considered, I'd rather have the hair trigger.

As a side note, I checked my old Hawken rifle that I found at a swap meet and found that you have to set the trigger to cock the lock.

[KentSmith]

Triggers arent setting. File metal off the rear trigger platform not the mainspring. Once you have the rear trigger floating tighten the mainspring screw. A screw to adjust the mainspring is redundant if you tune the rear trigger but if it works for you its your time.  Make sure the front spring id engaged and working.  Soot up the whole device, put the triggers back in and make sure you have no wood contact.

[KentSmith]

I've seen this happen. Make sure when you put you lock in it is tight and in proper alignment not canted a bit.  As this can let the sear sit lower than it should. Trying to fit triggers, taking them and the lock in and out, getting frustrated sometimes lossens things up and the lock wont cock because it is slanted in relation to the barrel and stock. Not sure this makes sense. I just repaired a TN rifle that had the lock in slanted with the top in farther than the bottom. Same symptoms.

[P.W.Berkuta]

This is where some have suggested that an adjustment screw be installed to take the pressure off the heel of the rear trigger.  The screw is drilled and tapped into the trigger plate just behind the rear trigger.  A #2 or #3 x 56 screw works nicely, but be advised, it is very difficult to adjust without removing the trigger guard.  So tuning is your best option.

Like this?

I use an Allen set screw and once it is adjusted correctly I Lock-tite it in because the screw can move with it being repeatedly hit by the mainspring. If done correctly the set screw will not be seen as the Allen wrench screw end will be flush with the trigger plate.

[ltdann]

That's a great idea, thanks!