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LP2 - forward thrust on trigger after release

Posted: Tue Dec 14, 2010 9:59 am
by Bob (Name already taken)
Hi all,
I noticed that right after the trigger release point is reached there is a slight forward thrust on the trigger of my Steyr LP2. The trigger actually moves forward again a very small distance, against my finger pressure. Afterwards this disappears again and if I keep up the pressure, then the trigger moves back again until the overtravel is exploited.

Thus is is sort of a "bouncing" effect, although very slight. My interpretation is that the revolving sear touches the trigger catch and pushes it forward. Is does not matter how much overtravel I adjust.

If the effect is consistent then it may not be a problem, most likely I have already compensated my sights for any changes it may have on bullet impact. But I checked with another man's LP2 and there was no such effect at all, just a clean release.

What do you think? Is this a known issue, will it get worse or can I just disregard it?

Re: LP2 - forward thrust on trigger after release

Posted: Tue Dec 14, 2010 11:59 am
by scerir
it is possible that the sear engagement is too short. try to turn anticlockwise the screw of the sear engagement by a very very small amount.

same thing

Posted: Tue Dec 14, 2010 12:33 pm
by FredB
My Pardini K60 does exactly the same thing, and I can't get rid of it no matter how I adjust all the different trigger parameters. I can't figure out the cause, and it's rather distracting. I had a K58, which has exactly the same trigger components, and there was no "kick-back." Also, wasn't there some talk a while back about a similar problem with some Steyr LP10s? There's got to be an answer!

FredB

Re: same thing

Posted: Tue Dec 14, 2010 2:53 pm
by scerir
FredB wrote:My Pardini K60 does exactly the same thing, and I can't get rid of it no matter how I adjust all the different trigger parameters. FredB
Yes, also my K2 had a similar problem. At Pardini they use to say "questo scatto scalcia" (this trigger kicks). And they also change parts of the trigger.

But the case of the Steyr might be different, that kick is often due to a poor sear engagement. Of course one has to remove the trigger stop first, and then readjust it.

Re: same thing

Posted: Tue Dec 14, 2010 3:01 pm
by FredB
scerir wrote: Yes, also my K2 had a similar problem. At Pardini they use to say "questo scatto scalcia" (this trigger kicks). And they also change parts of the trigger.
Thanks for the information. So, do you know which trigger parts need to be changed?

FredB

Re: same thing

Posted: Wed Dec 15, 2010 3:36 am
by scerir
Thanks for the information. So, do you know which trigger parts need to be changed?
FredB

#541 and #534 (I presume)
http://www.pardini.it/manuali/k60-k90.pdf

Posted: Wed Dec 15, 2010 6:48 am
by Guest
This is not a Steyr LP2 characteristic, it is definately out of adjustment or displaying a fault. I have one and there are 6 more in my club all perfect. I would suggest an e mail to Steyr office@steyr-sportwaffen.com I'm sure they will tell you how to adjust it out.
Good shooting.
Robin

Posted: Thu Dec 16, 2010 12:15 pm
by Bob (Name already taken)
Thanks all for the feedback. I will probably have it repaired during summertime. The kickback is not a total show killer only a bit strange so I will wait for a calm time period without shooting.

Posted: Thu Dec 16, 2010 1:11 pm
by David Levene
I don't know how similar the LP2 and LP10 triggers are but you might find this thread interesting.

Posted: Thu Dec 16, 2010 2:10 pm
by Bob (Name already taken)
David, thanks for the link I did not find that topic when I searched. I think the LP 2 and LP 10 triggers are identical (except for the ball bearings), so I will definitely try that.

Posted: Thu Dec 16, 2010 2:13 pm
by David M
Trigger weight is usually made up of first stage spring, second stage spring (if fitted) and trigger sear friction. Normally once the sear friction is released the trigger weight will reduce.
If your tirgger is kicking forward after trigger release then the sear is trying to push off by itself (compensated by inceasing the spring tensions) and you are feeling this extra spring tension pushing the trigger forward.
Possible causes are -
1/ the sear has too little engagement and is sitting on or over the round of the sear (put more sear engagement on the trigger) or
2/ The sear angles are incorrect and slope the wrong way (usually on a secondhand pistol when someone has ground the sears not knowing what they are doing). New parts or regrinding is required (gunsmith job).

Posted: Tue Feb 08, 2011 4:03 am
by greentangerine
My coach noticed that my LP2 had the same kickback problem with the trigger (and also had no overtravel).

Adjusting the overtravel screw didn't solve the kickback; adjusting the sear screw (i.e the one with the red paint blob) was the answer.

I adjusted it anti-clockwise in small increments and let the change bed-in; took three attempts to get rid of the kickback and the screw has probably been adjusted about an 1/8th or so out by the time I'd finished.