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how to divide first pull and second pull pressure in morini

Posted: Sun Jul 03, 2005 1:25 pm
by shradhapn
i am having morini 162 E1.how much should be the pressure for first pull and second pull.means how to divide trigger weight in first and second pull.my trigger weight is more than 500 gram.in case if i keep the pressure only 500 my trigger releases before coming on targer and in case if i increase the pressure i cannot squezze it.please give me the guidance for the right trigger pressure

Posted: Sun Jul 03, 2005 6:03 pm
by GOVTMODEL
Most folks prefer to have the first and second stages about equally balanced, i.e., ~250 grams for each stage. Too much first stage makes the second stage hard to control.

second trigger stage weight

Posted: Mon Jul 04, 2005 6:21 am
by M162ist
I prefer about 350 - 400 grams first stage and 150 - 100 grams second stage.
A few (very good shooters, by the way) prefer a second stage pull weight of only 80 grams on their APs. But then for me at this light 2. stage pull some shots may fire inadvertedly.

A relatively heavy 2. stage demands for a firmer hold. For some this could mean more shaking of the hand. But this is individual.

Good air pistol is kind of fine art.

Posted: Mon Jul 04, 2005 8:03 am
by Steve Swartz
Shradhapn:

Do you have instruction manual showing how to mechanically adjust the two stages (small hex head adjustment screws behind trigger) or is your question more about what settings are preferred?

Steve Swartz

Posted: Tue Jul 05, 2005 9:08 pm
by GaryN
If I understand you right, you are trying to adjust the trigger weight to time the release when you are lowering the pistol and in the black when it goes off. If this is the case, then you are timing the shot, rather than holding on target.

I don't recommend that because besides everything you then have to have your pull begin at the EXACT point in space, and for the same rate, and your lowering speed has to be EXACT. Too many vairables to coordinate and have to get correct.

Holding on target, even for 3 seconds is better than trying to fire while the pistol is in motion (going down).


For the weight go for something like 550 grams. Why 550? Because not all weights are the same, and temperature may make the trigger behave differently. 550g gives you a 50g margin before your trigger fails the test. I set mine up for 520g at home and it failed the test a month later after traveling and in warmer temp. Cut it too close and you risk not passing the trigger test.

As for weight split. Hate to say this, but it is personal. The 2 used APs that I bought from Pilkingtons both had their 1st stage dialed out, and thus were single stage triggers. I prefer a 2 stage trigger, and had to put the 1st stage back in. Warren recommed to me to use a 50/50 split. The book "ways of the rifle" the author recommends single stage. So there is no ONE best way. My recommendation, pick one and work at it. If you have a coach, do what your coach recommends.

gud luk
Gary

trigger weight

Posted: Wed Jul 06, 2005 7:30 am
by GADoug
I'm confused.

Are you saying you can combining the two stages of trigger weight to a total of over 500.

Does the first stage weight have anything to do with what the second stage breaks at?

Is the first stage set at less than 500 (personal preference) and the second stage over 500 to be legal (550)?

Posted: Wed Jul 06, 2005 3:52 pm
by Steve Swartz
GA Doug:

Yes, it's confusing but actually quite simple on the Morini. You have two separate springs entirely. The first stage spring is set below the desired total weight, and the second spring is set to be "additive" in order to bring the total weight up to the desired (legal) weight.

So the weight distribution would be something like 400 grams on first stage and an additional 120 grams on second stage. Felt pressure would be 400 -> 520.

Also note that on the Morini (not a mechanical trigger) alone, the trigger pressure does not immediately jerk to zero when the shot is fired.

Steve

Posted: Wed Jul 06, 2005 4:01 pm
by David M
When you pull the trigger on a Morini you pull both springs (1st and 2nd stage) to release the shot.
The 500g weight is split between both stages.
You must have some weight on the second stage as it holds the trigger bar against the switch housing.

If you want a single stage trigger, you adjust out the first stage travel until the second stage travel point.
You will only feel a single stage, but you are pulling on both.

The better way to set up is two stage with anywhere from 250-450g on first stage, and 50-250g on second, so that the total just exceeds 500g by a safe margin (put 2 or 3 coins extra on the weights to test).

You need enough weight on second stage to be able to feel it. I set 400-420g on first stage and 80-100 on second but with less experience you may need a little more on second stage up to 150g.

Posted: Wed Jul 06, 2005 9:56 pm
by bluechucky
I have a problem of jerking the trigger. Is there a 1st/2nd stage split that is ideal in order to help remove this problem? Are there any training drills that are of particular benefit to this problem?

trigger weight

Posted: Thu Jul 07, 2005 2:52 pm
by GADoug
Steve,

Great explanation.

I knew it had two seperate springs but did not know they worked independently with the 2nd stage being an "additive" spring.

Many Thanks, Doug

Posted: Thu Jul 07, 2005 7:54 pm
by Steve Swartz
Bluechucky:

The 1st/2d stage settings that will cure trigger jerk is called "dry fire practice."

Seriously.

However, what you need is a trigger force profile that doesn't change as the sear is released. That is called a Morini Electronic Trigger.

Failing *all* of that, many mechanical trigger shooters believe that by increasing the first stage pressure to "very close" to the second stage pressure (the definition of "very close" is fraught with peril!), you reduce the differential increase in pressure associated with trigger jerking.

Great theory- however, with virtually all mechanicl trigger systems even if you have 499g-500g split you will still have the instaneous drop to 0g just at the most inconvenient moment when the pellet is travelling down the barrel.

Which brings us back to solution 1), dry fire training and practice.

No quick nor easy fix in any case. Proper grip, proper position of finger on trigger, and have a constant force spring that doesn't violently drop to zero grams as the shot is released.

Steve Swartz

Posted: Thu Jul 07, 2005 9:38 pm
by GaryN
bluechucky

Let me tell you what worked for me (may not work for you but it might).

I dry fired but pulled the trigger VERY SLOWLY, not caring where the sight was aimed at. This was to train my trigger finger to pull SLOWLY rather than jerking. And to pull STRAIGHT BACK. Do this enough times and you get your finger trained.

Then you have to train your brain.
Hold on target, and accept that you wobble, then begin the SLOW pull.
Get the shot of within 8 seconds +/- or put the pistol down.

If your wobble get BAD, put the pistol down.
If you feel "unsure," put the pistol down.
If your arm is tired, put the pistol down.
If you get distracted, put the pistol down.

Aborting a shot is a lot harder to do than say, but you have to have the dicpiline to abort the shot...or your shot is even worse, trust me on this :-(

As you practice better and more, your wobble gets smaller and your scores go up...amazing :-)

gud luk
Gary

Posted: Thu Jul 07, 2005 9:58 pm
by bluechucky
Thanks Steve, Gary. Really appreciate it.

Posted: Thu Jul 07, 2005 11:52 pm
by Denis
Steve,

What are you refering to that drops to zero at the trigger release on mechanical AP triggers?
I take it you mean the second stage spring pressure.
How can this be when the second stage spring pressure can still be felt after sear release?

Posted: Fri Jul 08, 2005 8:58 am
by Steve Swartz
Denis:

Thanks for correcting me on this (again, probably!). Yes, there is some residual pressure left over on a mechanical trigger, otherwise, the trigger wouldn't reset.

How many grams of "post break pressure" do you think we are talking about here?

The same as break pressure would be ideal- and IIRC some mechanical trigger designers attempt to do just that- alternately, fiddle with overtravel mechansims, etc.

The mechanicals I am familiar with drop off "Pretty Substantively" (although not technically to "zero" but still less than first stage pressure) immediately upon the release of the shot.

Anyone know of any match-grade mechanicals that maintain constant force beyond the break?

Steve Swartz

not zero, maybe not substantively

Posted: Fri Jul 08, 2005 10:20 am
by Fred
Steve Swartz wrote:
The mechanicals I am familiar with drop off "Pretty Substantively" (although not technically to "zero" but still less than first stage pressure) immediately upon the release of the shot.

Anyone know of any match-grade mechanicals that maintain constant force beyond the break?

Steve Swartz
Steve,

What do you think happens to the first stage pressure that is due to a spring? Most 2 stage triggers I have seen have spring-mediated first and second stage adjustments. Whatever spring pressure has been added to the force required to trip the sear, remains after the sear is released. This is not an insignificant amount, and nowhere near zero. For example, I adjusted my Pardini K-58 to have minimum total pressure required for release - i.e. I backed off the first and second stage springs as much as possible - resulting in an approximately 100 gram release force. Therefore on that gun the remaining spring resistance after sear release when the trigger is set to 500 grams would be about 400 grams.

Conversely, on the Morini 162E that I had, I definitely felt a change at the sear release point, although I don't know what mechanics caused that change. In any case, the lack of a trigger stop on that gun always bothered me.

FredB

Posted: Fri Jul 08, 2005 11:21 am
by Steve Swartz
Fred:

Right- I am aware that some designs have less "drop off" than others. My Hammerli used to drop off to well below the first stage pressure however.

And honestly, I don't know "where the first stage pressure went" at all. Maybe this was a result of leverage somewhere internally and how the springs were attached?

Some may drop off only to the first stage. In that case, shooters may attempt to reduce the drop-off by adjusting the first stage very close (my previous comment) to the second stage, making the drop off smaller. That presents it's own problems, however.

This appears to be a quite sensitive topic for many posters. Sorry to bring it up.

What guns drop off to first stage pressure, and which drop off to less than first stage pressure? Are there any mechanicals that don't drop off at all?

Steve

the sear?

Posted: Fri Jul 08, 2005 2:13 pm
by GaryN
Without knowing the mechanics of the different triggers, I would guess that "some" of the weight might be from the drag/friction against the sear. Once the hammer releases, the friction drag is gone, and all you have left is the spring.

Gary

Posted: Fri Jul 08, 2005 8:39 pm
by Steve Swartz
Gary:

Right- overlooked that. On some mechanical designs, the first stage is nothing more than "take up slack" with a stout spring to add resistance. On those designs (don't know if *any* match grade APs use this though- some powder guns do), you have the take-up pressure, then the "second stage" is actually where you are engaging the sear; then you have some non-zero (and I'm *sure* about this part!) movement as the sear slides off the hammer hooks/contact point whatever- this is called "creep" when it is really ugly; but even the Toz FP has some sear sliding- then finally the sear releases and you are back to pulling on the take-up spring.

So you really have slack-creep-release-recover forces in play. The slack pressure represents the "first stage." The "creep" is ignored in polite company; the pressure required is the "second stage." Then you have the sharp reduction in pressure back to some "recovery pressure" which is at least the same as the first stage?

Let's say you have slack pressure set at 400 grams and the creep pressure required is 500 grams.

You really want to whack your finger with a 100 gram ball-peen hammer as the pellet is sliding down the bore?

Maybe I should have never given up on Service Pistol . . .

(running, ducking, grinning)

Steve Swartz

Posted: Sun Jul 10, 2005 8:45 pm
by GaryN
Steve, I was indoctrinated in the ZERO creep, breaks like a glass rod thinking from years of reading the various gun mags. Then after picking up AP, I talked with Warren...now I'm shooting my AP with a rolling trigger (aka creep) and I like it. Funny how things change.

I also have a tendency to throw shots at 10 o-clock and Warren suggested I adjust the trigger stop to catch the trigger right after the sear releases. So I really don't have a drop in tension, I simply hit the trigger stop and don't deal with it.

But to what you mentioned 'service pistol'...I still like a 45s grip. Don't know why, but it is comfortable to my hand, even though the grip angle is very different than my Walther CPM-1.

Gary