Trigger pull weight

[flatsguide]

Please bare with me as I explain my question. I have done quite a bit of competitive rifle and pistol shooting,mostly modern arms, in the sixties and seventies so I am used to crisp trigger pulls with no apparent movement and no overtravel. In the early seventies I built a longrifle flintlock from a blank with a Siler lock and a Large barrel. It was like a Beck but had double set triggers so I really did not worry about the feel of the sear engagement to the fullcock notch in the tumbler. Now I am planning to build a English Sporting Rifle and a JP Beck rifle, both with simple ( yeah, right) single triggers. With this type of trigger I will be concerned about the feel of the sear engagement and trigger pull weight. I will be looking for about 2 1/2 to 3 pound pull. I have a round faced Chambers lock that I will use on the the English sporter. When I hold the lock in my hand, at full cock, it takes a considerable amount of force to trip the hammer.
Now the question...knowing there are variable on the the actual trigger/sear bar geometries. What would a ballpark figure be if the trigger pull scale was pulling on the sear bar instead of the trigger? Assuming the trigger scale would show the above desired weights. It would be a lot easier to work on getting a nice trigger without having to remove the lock. Am I making sense here?
Thanks, Richard

[Mark Elliott]

If I understand you,  you are making this too complicated.   Just tune the lock normally for a single trigger (all bearing surfaces smooth and a slight radius on the sear to reduce the force required for it to come out of the full cock notch) and pin the trigger high for as much mechanical advantage (leverage) as possible.    If you do this with a Chambers lock,  you will probably end up with 2lbs or pull or less.   You can try to figure your pivot distances exactly,  but I think it is an unnecessary waste of your time.  After all, your are not building a gun with a super sophisticated modern trigger assembly.    Don't think that you are going to be able to get the same results.   If that is what you want,  build a modern target gun. 

[David R. Pennington]

Peter Alexander has some good info in his book on trigger set up. I did one a while back with a Chamber's rd. faced lock on .62 with single trigger and the pull is very light, almost too light for gloved hands. I tuned lock as Mark suggests and pinned the trigger in the stock up fairly high. The position of the pin forward and backward have some bearing on function as well.

[Ky-Flinter]

Hi ya Flatsguide, welcome to ALR.  Good info above and more to come, I'm sure.

I used the Search function here and found this from a few years back.... http://americanlongrifles.org/forum/index.php?topic=21363.0

Hope it helps.

-Ron

[Bob Roller]

If I understand you,  you are making this too complicated.   Just tune the lock normally for a single trigger (all bearing surfaces smooth and a slight radius on the sear to reduce the force required for it to come out of the full cock notch) and pin the trigger high for as much mechanical advantage (leverage) as possible.    If you do this with a Chambers lock,  you will probably end up with 2lbs or pull or less.   You can try to figure your pivot distances exactly,  but I think it is an unnecessary waste of your time.  After all, your are not building a gun with a super sophisticated modern trigger assembly.    Don't think that you are going to be able to get the same results.   If that is what you want,  build a modern target gun. 

 An English style lock like found on a Rigby or other TOP of the line muzzle loader can be tuned to a vary light pull because the bridle has 3 or 4 screws going thru to the lock plate and is  very rigid and if the sear is on a pin with .0005 or less rotational clearance then a good pull is easily obtained.This presupposes the two axles of the tumbler are also this close.

Bob Roller

[flatsguide]

Hey! Thanks for the welcome and replies.What prompted the original question was the holding the lock at full cock it took considerable pressure with my thumb to release the sear.
David, I have Alexander's book and it does cover triggers very well...Thanks

Ron, Thanks for that link. Good visual info.

Bob, The Chambers lock only has two screws holding the bridle. Interesting about the Rigby triggers.

Mark, the last thing I need is complications.

Thanks fellows....Richard

[kaintuck]

aaahhhhh.........leverage~~~

1/4"sear bar distance from the trigger pivot point~~~~~

marc n tomtom

[Dr. Tim-Boone]

You can always get a Stan Hollenbaugh Double action single set trigger. nice early shape and a fine release mechanism that if positioned properly will fire a Large English lock fine. I have one with an English Round-face and one with an early Ketland.... just cause I like them.

The S.H. single set trigger can be used either as a single
stage trigger or set.
It is adjustable for both setting pressure & release
pressure when set & no trigger creep. The lock must
have a sear release pressure of five (5) pounds or less.
Warranter against defective parts or workmanship as
long as not altered.
Comes with installation instructions. I am told that it's the
best one available!
 $65.00 plus shipping & ins.

http://www.stanhollenbaughgunsmith.com/page4.html

[D. Taylor Sapergia]

Marc - I have to disagree with you on sear trigger pivot location.  I concur that at 1/4" trigger pivot from sear pivot screw, you'll get lots of mechanical advantage and a light trigger pull.  But the trade off there is that you'll get so much creep before the trigger breaks - it'll drive you to substance abuse.  To avoid that I simply tune the lock as has been mentioned in another most recent thread, and end up with a simple trigger pull that is less than 4 pounds easily, yet is crisp and positive.

[flatsguide]

I think Doc answered the question I had about the the lock sear release pressure, it being around five pounds. From that I can find the mechanical advantage needed to get around a 3# pull.
I was looking at a Hollenbaugh lock today for the Beck I plan on building. That single set trigger looks like just the ticket for the English rifle, although I'm not sure about the shoe shape.
Thanks again for the help fellows, What a great site
Regards, Richard

[Daryl]

I think many guys think 3 pounds is a heavy trigger.  It was not too many years ago, that match triggers had to pick up a 3 pound weight or be disqualified - modern guns. They reduced it to 1 kilo - WOW - felt like a set trigger - of course, our triggers were wider than the thin sticks used in many ml's.  They "feel" stiffer due to the small contact surface, so it's easy to go to far in lightness.

A 2 pound trigger that is crisp, is indeed a nice trigger and good work can be done with it.  A lighter trigger than 3 pounds can sometimes get you into trouble when hunting in cold weather - gloves and all

[flatsguide]

Trigger pull weight is a personal thing and dependent in large part on the use the firearm will be used for. I think we can all agree that a crisp no creep tigger pull trumps trigger pull weight within reason. It seems like the trigger pull on the run of the mill rifles these days exceeds the weight of the rifle. That probably comes from corporate counsel. I have heard it said the trigger release should be like "breaking a thin glass rod"....pressure, pressure pressure then Snap. But then there are release triggers...
Regards, Richard

[Mark Elliott]

When I was shooting rifled muskets in the N-SSA where they all had simple triggers,  the pull could be no less than 2 lbs.   Most of us tuned up our locks until the pull was just enough over 2 lbs to pass the safety inspection with a static 2 lb weight.   The trigger/half cock notch did have to hold the weight of the gun to pass inspection.   I don't know what guns have the kind of heavy trigger pull you describe except for maybe the unset front trigger of double set triggers.  However,  must of my guns have double set triggers and I usually manage to get an unset pull on that front trigger of about 2-3 pounds.   I usually aim for about a half pound of pull on a set front trigger.    Getting the pulls I want with set triggers usually involves very precise placement of the triggers and many times very precise bending (hot with re-heat treatment) of the sear bar. 

[Don Stith]

Totally different world, but modern benchrest rifle triggers are frequently under one ounce these days

[Bob Roller]

Totally different world, but modern benchrest rifle triggers are frequently under one ounce these days

Under one ounce? Is this what the Swiss called the "weight of a shadow"?

Bob Roller

[D. Taylor Sapergia]

I made a single set trigger for my Hawken pistol, back in the late 70's.  It is adjustable for weight.  I had it so light once, that I lost a duelling match against my brother.  We were required to start with our pistols pointed straight up...the weight of the trigger set mine off, and he had all the time in the world to hit his target, which of course, he did.

[Daryl]

I like my DSet/DThrow flinter's triggers (.32 and .45) to run in the 6 to 8 ounce range. My single, simple triggers run 2 to 2 1/2 pounds.  There is a HUGE difference in feel, between a 3/8" to 1/2" wide trigger at 2 1/2 pounds and an 1/8th or 1/16" inch wide trigger at the same pull weight. 
That is why trigger shoes were invented long time ago.

[Don Stith]

Bob
 I dont know what the Swiss call it. The only original swiss triggers I have ,provide a post to rest your finger on. The actual release trigger is a wire beside the post. Don't think my modern trigger pull scale will work on it. They only go to 1/2 ounce
 I always wanted to take those things apart, but not sure I could get all those levers back in place

[Bob Roller]

I made a single set trigger for my Hawken pistol, back in the late 70's.  It is adjustable for weight.  I had it so light once, that I lost a duelling match against my brother.  We were required to start with our pistols pointed straight up...the weight of the trigger set mine off, and he had all the time in the world to hit his target, which of course, he did.

About 35 years ago I made a few single set triggers for a German customer and before I
 sent them I showed them to a friend.After examining them he said it was a study in controlled
instability and a fascinating mechanism.

Bob Roller

[Elnathan]

Marc - I have to disagree with you on sear trigger pivot location.  I concur that at 1/4" trigger pivot from sear pivot screw, you'll get lots of mechanical advantage and a light trigger pull.  But the trade off there is that you'll get so much creep before the trigger breaks - it'll drive you to substance abuse.  To avoid that I simply tune the lock as has been mentioned in another most recent thread, and end up with a simple trigger pull that is less than 4 pounds easily, yet is crisp and positive.

What would be your recommendation, generally speaking?

As an aside, putting the pivot point further forward can help with architecture too. My much-delayed current project is based on an original with what looks like at 3/4" between the pivot and the sear, which, combined with a 13" draw and a pretty hefty barrel, gives it a rather stocky appearance difficult to imitate with a longer draw and a smaller barrel. Keeping the pivot well forward will help keep things looking right, I think.