Author Topic: Creep!  (Read 6470 times)

Offline Roger Fisher

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Creep!
« on: July 31, 2009, 02:41:52 AM »
Yes Creep (in the lock) not me!

My latest fowler lock has a nice smooth let off; but some trigger creep which takes some getting used to for me....  My current shooter has no such creep. 

What do you folks do, live with it or stone the full draw notch more shallow???




Offline T*O*F

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Re: Creep!
« Reply #1 on: July 31, 2009, 02:48:42 AM »
Quote
stone the full draw notch more shallow???

Never a good idea.  It alters the radius of the tumbler and the sear will fall into the half-cock notch and break unless your lock has a fly, or you hold the trigger back until after the gun has fired.  What you want to do is shim it out.
Dave Kanger

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Offline Jim Chambers

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Re: Creep!
« Reply #2 on: July 31, 2009, 03:22:22 AM »
Trigger creep is usually caused by one of two things.  First, if the sear screw is smaller than the sear hole that play between the hole and the screw shaft must be taken up by the trigger before the sear nose can start to slide out of the full cock notch.  The other most often seen cause is trigger placement in relation to the sear bar.  If the trigger engages the sear bar too close to the trigger pivot pin you will get a light pull but a lot of creep.
Any modification to the cock notches should be done only by someone with extensive experience in lock work.

Offline P.Bigham

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Re: Creep!
« Reply #3 on: July 31, 2009, 03:26:20 AM »
 I stone the tumbler and sear down to a point that they are even in height. Then put a slight cant on the sear so more of it rides toward the outer edge of the tumbler, on the full cock notch. Hope this makes sense. If I were more computer savy I would draw a picture.
" not all who wander are lost"

Offline Dave B

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Re: Creep!
« Reply #4 on: July 31, 2009, 05:32:53 AM »
I had this problem with my Davis Jaeger lock and it was a too big of through hole on the sear. The sear moved up as the trigger pressed on the bar and made for a whole bunch of creep. The boys at the Davis booth at the CLA show took it back with them and sent it back to me working perfectly with a no slop fit.
Dave Blaisdell

Offline Dale Halterman

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Re: Creep!
« Reply #5 on: July 31, 2009, 02:12:58 PM »
I  had the problem of loose sear/sear pivot fit on two locks and improved it by wrapping a bit of brass shim stock around the screw to take up the slop. Not as good a job as sleeving the hole and reaming for a proper fit, but then I never claimed to be Jim Chambers. I don't even claim to be Jim Nabors.

Dale H

Offline Don Getz

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Re: Creep!
« Reply #6 on: July 31, 2009, 03:55:24 PM »
Roger......I think you probably have it pinned a little too close to the sear bar.   My last barn gun was pinned about 3/8"
in front of the sear bar and it too has some creep, pulls easy, but.   Solution woul be to re-pin the trigger, or there is another way.   You could heat and bend the sear bar toward the rear of the lock, in essence, you are lengthening the
ratio of the trigger pin to the sear bar.  I know, Jim is going to shudder when he read this, but people do a lot of strange
things to locks when they build a gun.   I did this recently on a gun built by a renowned gun builder so that the trigger would work and release the cock....this was an expensive gun, and real POS might I add................Don

Offline Roger Fisher

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Re: Creep!
« Reply #7 on: July 31, 2009, 04:34:32 PM »
Quote
stone the full draw notch more shallow???

Never a good idea.  It alters the radius of the tumbler and the sear will fall into the half-cock notch and break unless your lock has a fly, or you hold the trigger back until after the gun has fired.  What you want to do is shim it out.
She does have a fly! Happily

Offline Roger Fisher

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Re: Creep!
« Reply #8 on: July 31, 2009, 04:41:46 PM »
Trigger creep is usually caused by one of two things.  First, if the sear screw is smaller than the sear hole that play between the hole and the screw shaft must be taken up by the trigger before the sear nose can start to slide out of the full cock notch.  The other most often seen cause is trigger placement in relation to the sear bar.  If the trigger engages the sear bar too close to the trigger pivot pin you will get a light pull but a lot of creep.
Any modification to the cock notches should be done only by someone with extensive experience in lock work.
No play in that sear screw hole...    I tend to think I got a frog hair too close to axle -----   Your last sentence was fully expected under todays circumstances and certainly correct!!  I have actually bent a sear bar towards the axle yrs ago to gain a better trigger pull and it worked...  I wonder about bending this one 'away' from said axle a bit I'm only thinking as I type and probably am wrong in thinking that may quell the creep ??? ::)

Offline Roger Fisher

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Re: Creep!
« Reply #9 on: July 31, 2009, 04:45:01 PM »
Roger......I think you probably have it pinned a little too close to the sear bar.   My last barn gun was pinned about 3/8"
in front of the sear bar and it too has some creep, pulls easy, but.   Solution woul be to re-pin the trigger, or there is another way.   You could heat and bend the sear bar toward the rear of the lock, in essence, you are lengthening the
ratio of the trigger pin to the sear bar.  I know, Jim is going to shudder when he read this, but people do a lot of strange
things to locks when they build a gun.   I did this recently on a gun built by a renowned gun builder so that the trigger would work and release the cock....this was an expensive gun, and real POS might I add................Don
Holy Kats I had that very thought b/4 I read your response Thankee!!!

Offline rich pierce

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Re: Creep!
« Reply #10 on: August 01, 2009, 06:47:09 PM »
Learned something today.  Thanks, Don!  Bending the sear arm is something I never would have thought of.
Andover, Vermont

Offline J. Talbert

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Re: Creep!
« Reply #11 on: August 01, 2009, 07:15:45 PM »
Don,

I'm not sure about this, but I am intrigued.  I'm thinking that the critical measurement is the pivot point of the trigger to the pivot point of the sear which has remained unchanged.

By bending the sear bar you lengthen the lever of the trigger, but you lengthen the lever of of the sear also by the same amount resulting in a net change of zero???   ::)

What say others???

Jeff
« Last Edit: August 01, 2009, 07:29:32 PM by Jeff Talbert »
There are no solutions.  There are only trade-offs.”
Thomas Sowell

Offline Don Getz

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Re: Creep!
« Reply #12 on: August 01, 2009, 08:02:24 PM »
Jeff......the reason I mentioned this solution is because I did it just recently.   I had a friend bring a custom gun into the
shop, built by a well known maker, and he had the trigger pinned only about 1/4" from the sear bar.   We could not get
enough movement out of the trigger in order to relaese the sear.   I thought of bending the sear, which I did, and it worked.   I will admit, these were unusual circumstances.   I would love to tell you this builders name but it would create
a major disruption in the forum.  See me at the CLA............Don

northmn

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Re: Creep!
« Reply #13 on: August 01, 2009, 08:21:30 PM »
Sears have been bent in a variety of ways for different reasons.  Have done so to get clearance for DST's.  Remember to heat sink the proper areas, like in a vise so that you do not have to retemper.

Offline Roger Fisher

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Re: Creep!
« Reply #14 on: August 02, 2009, 02:58:29 AM »
Well boys I 'operated on that sear bar last night.  Jammed her into the small bench vise got the propane cooking got the bar red hot and bent her Umm too far - 2nd heat bent her 'some'  Turned out I had to use a combo of opening that sear hole in the mortice a bit and ground down then polished said sear til she schnicked nicely in tofull draw.  Dry firing at my neighbor's car door moulding seemed to have no more creep and still a nice let off.   Jeez have we discovered a new cure Are you reading this Davy Rase  ??? ;)  Just kidding.  Nothing new under the sun!