Trigger stops
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Trigger stops
Do u ppl use the trigger stop? What is the benfit?
Re: Trigger stops
For me, the "trigger stop" is the second travel of the trigger. I use a very small or inexistent second travel, many pistol shooters like´s a more large second travel, because they like to feel the second travel, is part of personal adjustment of the trigger, and is part of your technique._Axel_ wrote:Do u ppl use the trigger stop? What is the benfit?
Nano
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Steve Swartz
Axel, Meaning of course, no, or almost no, perceptable movement of the trigger after the shot breaks. I was able, after a lot of lockwork honing, to have in effect, an MP90 trigger on my MP95 (Benelli), by installing a stop screw through the rear of my trigger guard. Care must be taken when adjusting these srews, to assure complete clearance of parts eg: sear-hammer notch. to avoid damage to same. Usual proceedure is to back off stop screw intill shot breaks, and then back off another quarter turn.Steve Swartz wrote:The purpose of the trigger stop is to make the mechanical trigger *almost* as good as an electronic trigger . . . =8^)
Steve
Paul
A contrary position - no trigger stop on any of my pistols. To help with follow-through, I want continued smooth motion until well after the projectile has left the barrel (the key word is smooth). And no, despite frequent statements to that effect, the trigger resistance does not drop to zero when the sear is released.
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2650 Plus
Trigger stops
If I cannot feel the sear release the firing mechanism as I press the trigger a stop doesn,t matter . If I can feel the release I try to adjust the stop close enough to eliminate the feeling .On at least minimize what I'm feeling. Hope this helps. Good shooting Bill Horton
I have also a very short travel after release.
The idea behind this choice is to minimize the trigger motion while the bullet is moving trhough the barrel to avoid any barrel movement after release due to trigger motion. The risk of barrel movement (in case of non perfect trigger pull, i.e. not perfectly in line with the barrel) increases when the trigger travel increases.
On some pistol (not match pistol), the trigger weight indeed decrease after the release meaning an accelaration of the trigger motion (because the shooter apply the same pressure but the resistance drops) that ends up with a shock at the end of the trigger movement. I have this effect on a H&K P7 pistol that also has a quite long travel after release.
Reducing the trigger travel after release + adding some amortizing material (rubber) at the end of the trigger travel reduce this shock.
The idea behind this choice is to minimize the trigger motion while the bullet is moving trhough the barrel to avoid any barrel movement after release due to trigger motion. The risk of barrel movement (in case of non perfect trigger pull, i.e. not perfectly in line with the barrel) increases when the trigger travel increases.
On some pistol (not match pistol), the trigger weight indeed decrease after the release meaning an accelaration of the trigger motion (because the shooter apply the same pressure but the resistance drops) that ends up with a shock at the end of the trigger movement. I have this effect on a H&K P7 pistol that also has a quite long travel after release.
Reducing the trigger travel after release + adding some amortizing material (rubber) at the end of the trigger travel reduce this shock.
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Steve Swartz
Just a minor correction- the purpose is not to eliminate "trigger movement" it is to reduce the sharp, quick reduction in resistance between the finger and the trigger at the moment of release.
But the implications of this "minor point" may be more significant than the semantics of the quibble itself:
Force doesn't have to drop from 500 grams to 0 grams for this "whiplash" effect to move the front sight. 500 grams to 400 grams would do it.
Without a trigger stop, you would have to grip the pistol harder, and work on being more diligent in finger placement, direction of trigger force applied, etc.
Of course you can shoot well with a jerky trigger (not jerking the trigger, but working with a trigger that havs "built in" mechanical jerk).
But you can shoot well with other handicaps too. Why make it harder for yourself?
Trigger stops work to reduce this whiplash based on the principle that a change in force "upwards" (hitting the stop) creates less of a disturbance in the balanced forces than a sharp, sudden reduction in force "downwards."
Steve Swartz
(There is of course the training benefit of working with a difficult trigger. Theoretically, mastering a difficult trigger would make you smoother/better on a good trigger? Maybe . . . )
But the implications of this "minor point" may be more significant than the semantics of the quibble itself:
Force doesn't have to drop from 500 grams to 0 grams for this "whiplash" effect to move the front sight. 500 grams to 400 grams would do it.
Without a trigger stop, you would have to grip the pistol harder, and work on being more diligent in finger placement, direction of trigger force applied, etc.
Of course you can shoot well with a jerky trigger (not jerking the trigger, but working with a trigger that havs "built in" mechanical jerk).
But you can shoot well with other handicaps too. Why make it harder for yourself?
Trigger stops work to reduce this whiplash based on the principle that a change in force "upwards" (hitting the stop) creates less of a disturbance in the balanced forces than a sharp, sudden reduction in force "downwards."
Steve Swartz
(There is of course the training benefit of working with a difficult trigger. Theoretically, mastering a difficult trigger would make you smoother/better on a good trigger? Maybe . . . )
Steve, Wouldn't the change in force, upwards or downwards, depend upon where the finger contacted the trigger, in relation to the verticle rotational point of the grip against the palm? Wouldn't there then be a neutral point, where the line of force intersected this pivot point, at which there would be no movement up or down? Just wondering,
Paul
Paul
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David Levene
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- Joined: Mon Mar 01, 2004 12:49 pm
- Location: Ruislip, UK
There is also the pivot point of the trigger (lever) itself to consider.pgfaini wrote:Steve, Wouldn't the change in force, upwards or downwards, depend upon where the finger contacted the trigger, in relation to the verticle rotational point of the grip against the palm?
If your finger is moving towards or away from that pivot, rather than in an arc around it, you will also induce a further upwards/downwards force (albeit hopefully small).
It always amuses me when people talk about the amount of fore and aft adjustment on their trigger. All that means is that there is more chance of it being in the wrong place in relation to the trigger pivot. Don't get me wrong, that relationship is less important than having the finger positioned properly on the trigger. It is however possible to get both things right by having expertly fitted grips. I don't know if any of the "grips by post" manufacturers take into account the correct trigger positioning in relation to the direction of force being applied on it when they are making grips. From what I have seen they seem more interested in just getting the lump of wood carved to fit the hand, rather than also considering where the trigger finger will fall on the gun.
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Steve Swartz
"force upwards" = increasing force
"force downwards" = decreasing force
sorry
(And if you want to introduce the vector aspect of it- of course that is relevant. If it were possible to design a gun and position your finger on the trigger precisely so that the unbalanced force couple [created at instant of shot release] went directly backwards in line with [not just parallel to, but in line with] the boreline of the gun, then no, the "jerk at the instant of shot release" wouldn't matter. However- think about it now- this is impossible. The "mechanical jerk" as the sear releases can never go directly through the boreline of the pistol . . . . on any of the currently designed match grade guns. So you will always have a vector made up of the drop in force along the line of force applied through the trigger [and of opposite sign] into the gun/hand system at the least convenient moment of the shot process. With low force drop between second stagte and follow through, and a force line that goes let's see now from pad of finger down to knee of shooter aligned in azimuth with boreline you would minimize, but not eliminate, the effect. Note that parallel to boreline in azimuth and elevation would create rotational moment around wrist fulcrum [which would be a Bad Thing].)
"force downwards" = decreasing force
sorry
(And if you want to introduce the vector aspect of it- of course that is relevant. If it were possible to design a gun and position your finger on the trigger precisely so that the unbalanced force couple [created at instant of shot release] went directly backwards in line with [not just parallel to, but in line with] the boreline of the gun, then no, the "jerk at the instant of shot release" wouldn't matter. However- think about it now- this is impossible. The "mechanical jerk" as the sear releases can never go directly through the boreline of the pistol . . . . on any of the currently designed match grade guns. So you will always have a vector made up of the drop in force along the line of force applied through the trigger [and of opposite sign] into the gun/hand system at the least convenient moment of the shot process. With low force drop between second stagte and follow through, and a force line that goes let's see now from pad of finger down to knee of shooter aligned in azimuth with boreline you would minimize, but not eliminate, the effect. Note that parallel to boreline in azimuth and elevation would create rotational moment around wrist fulcrum [which would be a Bad Thing].)
David, I thought about the trigger pivot point, and decided (right or wrong), that the amount of arc in the rearward travel would be negligable with regard to the rearward line of force, because it would move it vertically, parallel to it's original direction.
Steve,
If that's the case, ALL movement would be in a downward direction, since the line of force is below the centerline of the bore. But what if the majority of the forward pressure on the gip is down near the heel of the hand. Wouldn't any pressure above that spot result in an upward movement of the gun? I'm finding this topic interesting, since all of my gunsmithing with regard to target firearms, has been with rifles, in which this isn't a consideration.
Paul
Steve,
If that's the case, ALL movement would be in a downward direction, since the line of force is below the centerline of the bore. But what if the majority of the forward pressure on the gip is down near the heel of the hand. Wouldn't any pressure above that spot result in an upward movement of the gun? I'm finding this topic interesting, since all of my gunsmithing with regard to target firearms, has been with rifles, in which this isn't a consideration.
Paul
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David Levene
- Posts: 5617
- Joined: Mon Mar 01, 2004 12:49 pm
- Location: Ruislip, UK
You may be right Paul, I'm not sure, but remember that a vertical movement is just as disruptive as a horizontal one.pgfaini wrote:David, I thought about the trigger pivot point, and decided (right or wrong), that the amount of arc in the rearward travel would be negligable with regard to the rearward line of force, because it would move it vertically, parallel to it's original direction.
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Steve Swartz
Paul:
The gun in the hand (not enough recoil in AP to consider the elbow and shoulder) makes up a "system" of joints and struts that can be solved as a bunch of vectors tied together using "Statics" (sophomore engineering flashback time).
As with any good engineering problem, let's first simplify and write off a whole bunch of stuff as "insignificant" like the amount of "cushioning" provided by flesh, the boundaries between skin and gun, etc. etc.
What we are left with is an "L" shaped form that pivots at the bottom of the L (where the wrist pivots). Along the long part of the L, a pivoting lever (the trigger) hangs down. Visualize the appropriate angles and distances.
Just prior to the sear breaking, you have a set of forces that are in perfect balance- 500 grams of forces balanced through the trigger lever, and a torque around the wrist pivot to hold the muzzle upright. At the moment of shot release, a couple of things happen:
- the triggger resistance drops suddenly; and
- recoil forces from the release of gas and pellet being pushed down the barrel
As to the trigger force dropping, this creates a torquing force through the trigger pivot . . . in the same direction as the wrist torque (muzzle upwards? I think; since the trigger force was being held against the wrist pivot when stabilized.) With a trigger stop, the force increases, and the torque is "muzzle down."
However, with the shot breaking, the force is applied suddenly at the moment of release; with a trigger stop, the force is applied over a longer period of time and with a slight delay. Perhaps long enoung for the pellet to be gone . . .
Steve
The gun in the hand (not enough recoil in AP to consider the elbow and shoulder) makes up a "system" of joints and struts that can be solved as a bunch of vectors tied together using "Statics" (sophomore engineering flashback time).
As with any good engineering problem, let's first simplify and write off a whole bunch of stuff as "insignificant" like the amount of "cushioning" provided by flesh, the boundaries between skin and gun, etc. etc.
What we are left with is an "L" shaped form that pivots at the bottom of the L (where the wrist pivots). Along the long part of the L, a pivoting lever (the trigger) hangs down. Visualize the appropriate angles and distances.
Just prior to the sear breaking, you have a set of forces that are in perfect balance- 500 grams of forces balanced through the trigger lever, and a torque around the wrist pivot to hold the muzzle upright. At the moment of shot release, a couple of things happen:
- the triggger resistance drops suddenly; and
- recoil forces from the release of gas and pellet being pushed down the barrel
As to the trigger force dropping, this creates a torquing force through the trigger pivot . . . in the same direction as the wrist torque (muzzle upwards? I think; since the trigger force was being held against the wrist pivot when stabilized.) With a trigger stop, the force increases, and the torque is "muzzle down."
However, with the shot breaking, the force is applied suddenly at the moment of release; with a trigger stop, the force is applied over a longer period of time and with a slight delay. Perhaps long enoung for the pellet to be gone . . .
Steve
Steve, I'm prone to believe the forces necesssary to pull the trigger, don't go back to the wrist pivot point, and so don't affect it. I believe these forces are contained between the trigger and the hand gripping the pistol.
Visualize a lemon squeezer type hand excerciser, the kind with two grips connected by a heavy looped torsion spring. Holding the excerciser with the arm outstretched, and squeezing it, needn't affect the angle of the hand/wrist joint, because all the pressures are contained within the hand proper. The angle of the excerciser will move, but independently of the hand/wrist angle.
Paul
Visualize a lemon squeezer type hand excerciser, the kind with two grips connected by a heavy looped torsion spring. Holding the excerciser with the arm outstretched, and squeezing it, needn't affect the angle of the hand/wrist joint, because all the pressures are contained within the hand proper. The angle of the excerciser will move, but independently of the hand/wrist angle.
Paul
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Steve Swartz
Steve, You've described a sudden, unexpected, catastrophic event. Not only would movement extend to the wrist joint, but there would possibly be injury to the hand. I squeeze a sponge rubber ball occasionally, to strengthen my grip, and find compressing it, in no way causes any change in my grip angle. As I sit here typing this, the simple act of extending my arm and squeezeing a clenched fist bears this out.
I wonder if Yur' Yev adresses this in his book. I'm going to check his anatomy and physiology chapters .
Paul
I wonder if Yur' Yev adresses this in his book. I'm going to check his anatomy and physiology chapters .
Paul
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Steve Swartz
Paul:
There is a simpler, more direct way to test this- either as a "thought experiment" or, better yet, actually do the following:
Suspend your cocked pistol (in dry fire mode) from a string(s) attached to the ceiling. using a stick (or string looped across front of trigger) go ahead and apply force straight back onteh trigger.
When the shot breaks, you will see a distinct and significant "jump" of the gun.
Unless, of course, you are soing this with a Morini electronic trigger, in which case you will hear a click with no movement of the gun at all.
Then try it again with a pellet. To see the trigger effect, you will probably have to film the gun- you will see a distinct "One-Two" jerk with a mechanical trigger system . . . you will only see the recoil from pellet with a Morini. The trigger recoil is a quite different animal from pellet recoil; both in direction and magnitude.
Try it and you will see what I am talking about . . .
Steve Swartz
(And yes I agree that you can grip the gun harder etc. to make up for the disadvantages of the mechanicla trigger. My point is, why would you want to handicap yourself on such a critical issue? No I don't own any Morini stock; no I am not getting paid for any endorsement!)
There is a simpler, more direct way to test this- either as a "thought experiment" or, better yet, actually do the following:
Suspend your cocked pistol (in dry fire mode) from a string(s) attached to the ceiling. using a stick (or string looped across front of trigger) go ahead and apply force straight back onteh trigger.
When the shot breaks, you will see a distinct and significant "jump" of the gun.
Unless, of course, you are soing this with a Morini electronic trigger, in which case you will hear a click with no movement of the gun at all.
Then try it again with a pellet. To see the trigger effect, you will probably have to film the gun- you will see a distinct "One-Two" jerk with a mechanical trigger system . . . you will only see the recoil from pellet with a Morini. The trigger recoil is a quite different animal from pellet recoil; both in direction and magnitude.
Try it and you will see what I am talking about . . .
Steve Swartz
(And yes I agree that you can grip the gun harder etc. to make up for the disadvantages of the mechanicla trigger. My point is, why would you want to handicap yourself on such a critical issue? No I don't own any Morini stock; no I am not getting paid for any endorsement!)