improving Trigger Pull- Woodsrunner

[t.caster]

A fellow shooter recently brought his Woodsrunner to me because the trigger pull was so heavy it effected his shoot scores negatively. He had built it in a class at Friendship. I was surprised to find the triggers pivot pin was .71" forward of the sear arm contact point. I'm not sure why this wasn't addressed in his class. Since this was a CNC machined stock with the holes pre-drilled, I suspect all of them are made the same. I hope Jim K. will shed some light on this.
I usually set a trigger up 1/4" to 5/16" from pivot point to sear arm for a smooth light pull. So we agreed to move the trigger back to that range even though the new trigger pull would be just over 13", which he was OK with. Obviously, that wouldn't work for everyone. I then had to extend the trigger mortice and the slot in the plate and locate and drill a new hole further back as seen in the pics. I reused the existing hole in the trigger. A slight bit of grinding and polishing was also required on the trigger bar for clearance at the sear arm when assembled. All this was fairly easy for an experienced builder, but not recommended for a beginner. See pics...
(BTW, Jack's score went up at the latest shoot!)

[Steeltrap]

On my most recent build I put the pin at 3/16" or perhaps a bit less. My trigger pull is 2-lbs as measured by my Lyman Digital trigger pull gauge.....in fact a little to light.

[P.Bigham]

I did the same thing on mine.

[EC121]

During assembly on mine I polished the sear bar and stoned the sear nose smooth. Then I rounded the top of the trigger bar and polished it. It had some machining burrs. Also added a touch of grease on the bar. It was fine after that.  No creep.

[okawbow]

I’ve assembled 3 Kibler Woodsrunners lately and the trigger pull is light and crisp on all of them. You must have something out of the normal on that one.

[J. Talbert]

Moving the trigger pivot closer to the sear arm will lighten the trigger pull, but will increase trigger creep prior to let off.
Everything is a trade off…

Jeff

[smylee grouch]

On some locks a slight improvement can be had if you stone a very small amount off the  sear spring.

[Scota4570]

I just checked my Woodsrunner. It has a glass smooth 3# trigger pull.  I did not touch it. 

[Jim Kibler]

I disagree with moving the trigger pivot point.  As mentioned you will have lots of creep compared to the original position.  As to lightening the pull, the locks do vary somewhat and we are working to make them more uniform.  I would suggest just sending the lock back to us if you would like a lighter pull.  We can do some things to help it out.  These involve polishing the sear notches very carefully, slightly rounding the sear tip and thinning the sear spring.

Again, I don't agree with the pivot point change.  If the lock is as good as it can be there is no need.  You'll end up with a 2-3 pound trigger with very little creep.  The best of both worlds.  I see even some accomplished builders use pivot distances in the range of 3/8" and I think this is way too short.  Especially when compared to original work.

[t.caster]

Thanks Jim, I'll try that next time, and nothing to prevent moving it back to it's original location.
Trigger creep is not as noticeable as you might expect.

[Steeltrap]

With that offer from Jim I'd send it back, move the pivot point back. If it makes it "more better" than it is now that's a win!

[Jim Kibler]

Shortening the pivot distance is an easy way to lighten the pull, but really not the best in my opinion.  With a lock that is set-up well, you should be able to have a light pull with a 5/8" pivot distance.  Again, this allows for less pull distance to release the lock.  For example if you go from 5/8" to 5/16" you will double the distance the trigger must move to trip the lock.

[83nubnEC]

I also had trouble with a heavy trigger pull on my Kibler Woodsrunner and sent it back to Jim for adjustment. When I got it back the trigger was a crisp 3.5# pull, down from nearly 6.5#.

[t.caster]

I learned this method from a Master Gunsmith years before Peter Alexander emphasized it in his builders how-to book. So it's not a new or rogue method.

[JasonR]

How about video demos? Visuals might settle this. Creeping sloppy triggers seem more a function of lock workmanship not pivot distance.

[rich pierce]

How about video demos? Visuals might settle this. Creeping sloppy triggers seem more a function of lock workmanship not pivot distance.

There’s a lot at play; many factors including sear tip, depth, angle, and smoothness of the full cock notch. But for any given lock in its current condition, pivot position determines trigger pull and creep. It’s a simple leverage physics thing.

[Bob Roller]

The Kibler Woodsrunner is a high end copy of a low end gun and the current lock far  and away surpasses anything seen on most American guns flint or caplock.The workmanship  in the lock,the spring driven device that makes the barrel useful IS important.The pinning of the trigger can negate the benefits of a quality lock and the Kibler lock is a high quality lock.Jim took one apart for me and everything about it shows top of the line thinking and manufacturing.
Bob Roller

[Dphariss]

If the lock is properly set up. I.E. sear to notch engagement and sear spring tuning, the distance from trigger pivot point to sear can be a lot more than .75 and still have a light crisp trigger.  IF you move it too close and the sear notch is too deep its easy to end up with a creepy trigger. Having built 3 Colonials all had trigger pulls in the 3 1/2 to 4 pound range and were very good “out of the box” (but the last has a SS trigger). Its not in the trigger as much as it is in the lock. If we, for example, look to the sear engagement of 19th c. Colt SA revolvers or even copies we get an idea of how small the sear nose/notch can be. But many mass produced locks are at least a little “off”.
I built a rifle with casting from TRS , Manton rifle lock, and it has, by conventional wisdom here, a horrendous distance from pivot to sear. But it has a light crisp trigger. Because the original lock maker set it up correctly. I would have to disassemble the rifle to refresh my memory but its about 1”.

[t.caster]

There is no question the Kibler lock the top of the line in terms of quality. However if the sear notch is a little deep (even if it's not) and both springs are VERY strong, it can take a bit of effort to overcome them. This one tends to break flints the main spring is so heavy. I will suggest he send it back for tuning.

[Dphariss]

The pivot is about where the trigger exits the trigger plate. Well ahead of the “shoe” the finger presses on.
This was a English trigger plate/trigger that Track of the Wolf used to sell.

And is will stand significant repeated shocks to the rifle without “falling” from full cock.

[Jim Kibler]

As to mainspring strength, I wouldn't suggest lightening it any.  A strong spring is a very good thing in my opinion.  As to flint breakage, we have sometimes seen this when using small flints in this lock.  We also like to use bevel down.  So, I would suggest checking flints, making sure they are appropriate sized and give a few flints a try. 

These are very fast locks for their size and this is in part due to the mainspring strength.

We would happily check out the lock at no cost and make sure everything is just right for you.

Thanks,
Jim

[Dphariss]

As to mainspring strength, I wouldn't suggest lightening it any.  A strong spring is a very good thing in my opinion.  As to flint breakage, we have sometimes seen this when using small flints in this lock.  We also like to use bevel down.  So, I would suggest checking flints, making sure they are appropriate sized and give a few flints a try. 

These are very fast locks for their size and this is in part due to the mainspring strength.

We would happily check out the lock at no cost and make sure everything is just right for you.

Thanks,
Jim

Exactly. Weak springs are a bad idea. IMO

[t.caster]

Update: I talked to the owner of the rifle I modified today at our club shoot and he called the trigger pull "perfect, and no creep that he could detect"
He has a digital pull gage and said the pull was between 5 1/2 and 6 lbs. before. Much too heavy for him to shoot accurately. Now he measures it at 1 1/2 lbs., which repeatedly called "PERFECT".

I researched back to my first gun building book "RECREATING THE AMERICAN LONGRIFLE" by Wm. Buchele & G. Shumway, copyrighted 1970. They state the optimal distance from sear to pivot point between 5/16" to 3/8" and as high as possible above the trigger plate (to paraphrase the authors).

[Waksupi]

During assembly on mine I polished the sear bar and stoned the sear nose smooth. Then I rounded the top of the trigger bar and polished it. It had some machining burrs. Also added a touch of grease on the bar. It was fine after that.  No creep.

People need to keep in mind these are kits, that need some minor polishing on contact points. I put a dab of grease to the bar, sear contact point, and mainspring and frizzen lock contact points. As you should do for regular maintenance on any gun. I do this on my overabundance of Trapdoor Springfields, and it reduces trigger pull way below what you would expect from a military rifle.

[alacran]

Shot 4.5 lb. single triggers for years. They can be shot extremely well. You just have to learn how. 4.5 is the minimum trigger pull requirement for Military rifle competition.