Trigger stop

[Mike S-J]

After practice today it occurred to me that we do everthing we can to make the release as smooth as possible. Part of this is the long follow-through.

Then the following occurred to me:

1). The pellet travels down the barrel relatively slowly
2). we apply enough force on the trigger to shift 500g+ and then the trigger comes to a full stop.

So here are my questions / musings.

Once the trigger finger has broken the shot, isn't its residual backward momentum / pull, especially against the solid resitance of the trigger mechanism, going to interfer with alignment whilst the pellet travels down the barrel?

Or is controlling that "pull-through" all part of perfecting a smooth release?

Wouldn't it be better to have a third stage on a trigger that progressively firms up the trigger after shot release? Effectively damping down the post-release forces applied by the trigger finger's built up energy.

Has this been tried ?

Is it pointless?

[Richard H]

After practice today it occurred to me that we do everthing we can to make the release as smooth as possible. Part of this is the long follow-through.

Then the following occurred to me:

1). The pellet travels down the barrel relatively slowly
2). we apply enough force on the trigger to shift 500g+ and then the trigger comes to a full stop.

So here are my questions / musings.

Once the trigger finger has broken the shot, isn't its residual backward momentum / pull, especially against the solid resitance of the trigger mechanism, going to interfer with alignment whilst the pellet travels down the barrel?

Or is controlling that "pull-through" all part of perfecting a smooth release?

Wouldn't it be better to have a third stage on a trigger that progressively firms up the trigger after shot release? Effectively damping down the post-release forces applied by the trigger finger's built up energy.

Has this been tried ?

Is it pointless?

That's why you should have overtravel in your trigger. I shoot a Steyr, but that is one of the good things about the Morini trigger because you are just pulling on spring tension the trigger force does not change after the trigger release. All you need is a little over travel, the pellet roughly spends about 0.001 seconds in the barrel (roughly 8" at 500 ft/sec).

[scerir]

[quote="Mike S-J"]
Wouldn't it be better to have a third stage on a trigger that progressively firms up the trigger after shot release? Effectively damping down the post-release forces applied by the trigger finger's built up energy.
[quote]

As far as I know Roberto Palamà (best Italian tuner, for match pistols, and possibly the best Italian firm in the field, seriously speaking) provided his Patros ('Patro' is the name of the firm) with a 'progressive' trigger stop (a spring was inside, and you could set that spring at your pleasure). I've tried the Patro 22l.r. in the late '70s. I remember that the trigger release was exceptionally smooth and that there was not backlash, or collapse, at all.
You can look at that trigger stop in this picture
http://www.robertopalama.com/immagini/P ... tro_M2.jpg
In general see
http://www.robertopalama.com/

[Steve Swartz]

The solution, of course, (as previously mentioned) is hte electronic trigger with constant force spring resistance.

O.K., assuming you don't want the right answer (for whatever reason) with mechanicals of current design you have a choice:

1) Letting gun move as force against trigger reduces to a very low level suddenly; or
2) Letting gun move as force against trigger increases somewhat to a moderately higher level as you squeeze against the trigger stop.

What you will actually experience is a little bit of 1) before getting 2). A great gunsmith can *almost* eliminate the amount of 1); some shooter will eliminate 1) in exchage for all 2) by making the forece required to crush the stop slightly your effective "third stage" (removing all overtravel).

Anyhow

Is this really an issue with 500 grams or less? Or is this really more of a theoretical discussion?

Obviously, with proper training the obvious disadvantages of the mechanical design can be overcome . . .

. . . or else none of the top shooters would be using them, right?

Sigh. Let the flames begin (again).

Steve Swartz

[Richard H]

Better scores through tinkering (as opposed to training).

[scerir]

Obviously, with proper training the obvious disadvantages of the mechanical design can be overcome . . .
. . . or else none of the top shooters would be using them, right?
Sigh. Let the flames begin (again).
Steve Swartz

No flames at all :-)
Just pointing out that the (mechanical) trigger of Pardini K2 does not have overtravel, collapse, backlash, etc.
But I'm not saying that you can do better scores using a Pardini K2 or a Morini 162 electr. Because, in my opinion, the 'collapse' cannot add extra damages if the shot has been released properly. But it does add extra damages if the shot was released badly. Does it make any sense?
(What about air competition rifles? Do they have a trigger stop?)

[BJ]

All you need is a little over travel, the pellet roughly spends about 0.001 seconds in the barrel (roughly 8" at 500 ft/sec).

It has to accelerate to 500, so I'll take a punt at 250 Avg (anyone in the least conversant with maths is welcome to join in here) which makes barrel time 0.0027 seconds. It probably accelerates faster in the first part of the journey so lets say 0.002 seconds.

Which by my calculations is not very much.
There must be a lot going on (time taken for mechanical processes to happen) before the pellet starts its movement down the barrel.

[Ed Hall]

Because, in my opinion, the 'collapse' cannot add extra damages if the shot has been released properly. But it does add extra damages if the shot was released badly. Does it make any sense?

Consistency trumps everything else. If you perform consistently, and the mechanics perform consistently, the shots will be consistent. IOW, through training, you will "learn" to work within the parameters of the mechanics. OTOH, if you are inconsistent, the mechanical trigger can exaggerate your inconsistency. In this respect, the use of a gun with no overtravel might give you a slight edge, but that edge would only be realized at the lower levels of performance. The elite shooters would probably find no difference.

Take Care,
Ed Hall
http://www.airforceshooting.org/
http://www.starreloaders.com/edhall/

[Bruce Martindale]

A fair question and some good answers. I had similar questions and would like better answers and understanding of the phenomenon. I wondered if it related to the ratio of sear force to spring force and I did an experiment to find out. The thought was that in a 45 for example, the sear force is fairly high and when it is relieved, the gun is free to move by the change in force between spring + sear and that which is left after sear. If the center of grip pressure is low in the grip, then the trigger force creates a moment or torque on the gun of x in-lbs and the gun moves between the sear release and the end of trigger travel. If the grip pressure is up high and in line with the trigger then there is none.

I put a 45 on a Rika and dry fired both with and without a sear stop. Big difference on what the gun did during the shot. With an air pistol, no difference at all. The Morini actually has a 2nd stage spring that can act like a stop but it can move the gun too if you arent straight in your pull. The Steyr has the sear force and then very little spring left and as Eric told me, "you can jerk tens all day long".

This is just one test and isnt a thourough answer but it may be in the right direction

[Steve Swartz]

Bruce:

Yep- that checks with what I was trying (badly) to say. The problem isn't "The Gun Is Free To Move" after release *but* that once "free to move," the gun WILL move as a result of the force imbalance.

As you and Ed have also noted, the inherent/unavoidable force imbalance that comes along with a mechanical trigger will be lessened by:

1) Less force in the first place (500 gram vs. 3 pound) and
2) Better trained operator/better technique.

I would argue at this point that while the unavoidable force imbalance (no matter how well trained you are, the forces *will* decouple from an engineering standpoint at the instant of release; it is physically impossible for you to pull straight through the muzzle so to speak) will be present, the combination of 1) and 2) above might put even the best athletes at a slight disadvantage; but hey, the disadvantage of training around a small force imbalance is probably peanuts compared to the negative effects of the stress of WORRYING ABOUT IT!

(I think that's a record-breaking run-on sentence, even for me)

Steve

[Bruce Martindale]

Yes. This is also why you can not stall out on the trigger and get a good shot. Think about it, the slower you go through this transition, the more time for the gun to move! Especially with heavier sear forces like a 45. I found that " it takes balls to really pull the trigger" You can get deep tens but with the occaisional 7. This is a different level of the game. You can only go so far trying to be careful with the trigger.

With my H 152 free electronic, I still have to FEEL and control the trigger. Trying to ever so carefully release it had poor results. A careful start with a determined, no going back pull yielded excellent results on the Rika and in live fire.

This however may also be related to elimination of "sympathetic" reflexes in the rest of the fingers, aka milking the cow. Which of course is a function of grip pressure and sear pressure. Lighter triggers need somewhat lighter grip pressure to be able to control them. 45 shooters seldom do well in Free but there are exceptions as this is too general a statement.

anyhow, also a ramble, but there are tidbits to chew on and try out.

[PETE S]

Is it possible that all of this mechanical versus electronic trigger comparisons and over-travel and sear force miss the point of where the problems really with shooting.

I believe that all the errors come not from whatever the trigger finger is doing but what the rest of the forearm, shoulder and muscles attached to the other three fingers and thumb are doing.

I would like to propose that whenever the sub-conscious release is initiated, or as is probably more commonly the case, the non-subconscious release is initiated, other muscles movements are initiated. The other muscle movements are one of the problems. Other problems would include not having the sights lined up exactly correct.

I would further propose that these other muscle movements come from some part of the central nervous system regardless of the trigger system. The change in feel or left off when the sear disengages is after central nervous system has sent the signals to initiate the other muscles movements. The question then may be does the difference between the electronic and

Using this logic to the extreme, one would expect the same results if the shooter was using a rusted Government Issue 1911 or the best electronic trigger. Improved triggers systems do improve scores. But have the electronic triggers made a break through to new world records?

I would propose that the differences between very good mechanical triggers versus the electronic triggers are muted point. Just like “shorter lock time,” the need for recoil compensation in an air pistol, and so on. All can help but the shooter makes these other issues insignificant.

I converted to the electronic trigger from the mechanical at someone’s suggestion after last years nationals. I really like the change (thank you, Steve) but I am still me. I would probably not go back again but I can not say that I bought any points with the change.