Steyr LP10 "puffing" after dry-firing...

[DFWdude]

I can dry-fire my LP10, as advertised, and it works excellently in this mode. However, once my dry-fire practice is over -- after releasing the trigger for the last time -- and then pressing the cocking lever down into the live-fire position, the pistol will emit a short, light, single "puff" sound. It's obviously venting air, albeit very little air, and has me concerned...

1) What is going on to cause this?
2) Would this be considered a "shot" if done on the shooting line at a match?
3) How to fix it.

It's just an annoyance to me, but I would like to adjust whatever needs to be adjusted to make it stop. Any advice welcome.

[Chia]

My evo does that. I always assumed it was just the cylinder making the connection with the rest of the pistol...

It sounds similar to the sound made by my air cylinder when I attach it to the air pump. I don't think it's an issue, just a design thing, but if anyone doesn't believe this, I'd like to know.

[Gwhite]

I suspect it is the result of the internal/hammer tapping the firing valve. When you dry fire, the mechanism blocks the striker so it doesn't hit the valve, but the striker is still being released. If you then lower the lever all the way without re-cocking, the striker continues forward and taps the valve. The striker is most of the way forward at that point, so it doesn't have much force.

The solution is to re-cock fully before lowering the lever to the firing position. That locks the striker back into its normal firing position. Normal procedure for many air pistols is to operate the dry fire selector (on or off) only when the pistol is fully cocked. On some pistols (Benelli Kite for one), it is impossible to switch to dry fire mode without cocking first, and it can be very difficult to disengage the dry fire mechanism without re-cocking. I checked the Steyr manual, and I was surprised they don't mention this.

[Chia]

One more thing. When you are done dry-firing, unscrew the cylinder (which you should be doing anyway) slightly from the pistol until you hear air escaping. Then lower the cocking lever all the way. I'll bet that you won't get the sound. That "put!" is something like those newfangled keister sensors on modern cars that remind you to latch your seatbelts: it's saying unscrew that cylinder from me before putting me away!

You should also perform this process when switching from dry to live-fire, you just rescrew in the cylinder after unscrewing it and lowering the lever.

[DFWdude]

I suspect it is the result of the internal/hammer tapping the firing valve. When you dry fire, the mechanism blocks the striker so it doesn't hit the valve, but the striker is still being released. If you then lower the lever all the way without re-cocking, the striker continues forward and taps the valve. The striker is most of the way forward at that point, so it doesn't have much force.

This makes sense. But I've owned several APs in the past. And none of them showed this quirkiness. (I used to manufacture muzzle brakes for just about every model from Pardini to Walther, to FWB to Steyr, so had experience with each.)

The solution is to re-cock fully before lowering the lever to the firing position. That locks the striker back into its normal firing position. Normal procedure for many air pistols is to operate the dry fire selector (on or off) only when the pistol is fully cocked. On some pistols (Benelli Kite for one), it is impossible to switch to dry fire mode without cocking first, and it can be very difficult to disengage the dry fire mechanism without re-cocking. I checked the Steyr manual, and I was surprised they don't mention this.

I have always dry-fired with a fully cocked pistol, of course. You suggest that I fully re-cock it and lower the lever to the firing position. Doesn't that leave the spring in its fully loaded position? I wouldn't want to store the pistol fully cocked, because the spring will take a set when stored away.

[Chia]

When you are done dry-firing a Steyr, depress the trigger to make sure it isn't cocked, unscrew the cylinder just enough to hear the hiss, and put the cocking lever all the way down. This will place it in a storable form. Keep the cylinder on, just unscrewed enough that it does not form a connection with the pistol.

[DFWdude]

One more thing. When you are done dry-firing, unscrew the cylinder (which you should be doing anyway) slightly from the pistol until you hear air escaping. Then lower the cocking lever all the way. I'll bet that you won't get the sound. That "put!" is something like those newfangled keister sensors on modern cars that remind you to latch your seatbelts: it's saying unscrew that cylinder from me before putting me away!

You should also perform this process when switching from dry to live-fire, you just rescrew in the cylinder after unscrewing it and lowering the lever.

I could unscrew the cylinder and vent the regulator, but I've always been taught that seals (in the gun) work most reliably when stored under pressure. I thought the same about regulators. So I leave the cylinder fully engaged while stored.

[Chia]

http://www.targettalk.org/viewtopic.php ... highlight=

Our host's answer to the question.

[DFWdude]

http://www.targettalk.org/viewtopic.php ... highlight=

Our host's answer to the question.

Concerning cylinders on or off, it answers some questions although other opinions differ...

Back to my original question, I read Chia's note that his EVO makes this puff sound when the lever is run home after dry-firing. Do other people experience this? And more important, can it be ruled an air discharge (shot fired) on an empty chamber while during a competition?

I ask this because in other disciplines, such as Field Target, any discharge of air during a match is counted as a shot.

[Rover]

It's obviously time for a total rebuild of your gun including a new regulator.

Ya shoulda bought a pumper.

[Chia]

Okay as I'm sitting here listening to my gun, it's not making the puff sound. I must have been mistaken. It makes a clicking sound, but no "puff." I strongly suspect that as gwhite noted, it's internal mechanisms resetting. I attached the cylinder, cocked the gun, dry-fired, then lowered the cocking arm completely and it "clicked". Then I raised and lowered the cocking lever again. No click. Repeated same action again. No click. Then I cocked the gun, dry-fired and lowered the cocking lever. Click.

For me at least, it's a mechanical component resetting.

Rover, there's a austin powers joke in there about certain swedish luggage items and I'm not going there. Happy shooting. And also I own an SSP!

[DFWdude]

It's obviously time for a total rebuild of your gun including a new regulator.

Ya shoulda bought a pumper.

Yet another constructive Rover post, as usual.

If a brand new LP10 EVO behaves this way, then there is no reason to assume anything is wrong with my 3 year-old LP10. Should be only a simple adjustment if someone will offer info on how to do it.

[Marc Orvin]

2) Would this be considered a "shot" if done on the shooting line at a match?

Yes.

[nick marshall]

I have owned several LP10's and two EVO 10's.

None of my LP10's does it. But both my EVO's did.
Asked Steyr UK about it. Told it was normal. So didn't worry anymore.

[Frenzy81]

My 5 year old LP10 started doing this earlier this year, after I increased the velocity. I hadn't touched the velocity setting since I bought the gun new in 2011, and up until then I never heard any puffing sound either.

I attended the national championships here in Norway and Megalink were testing out their new 3D score targets, which incidentally included a reading of pellet speed, when it passed through the two gates of laser sensors. I had never chrono'ed my gun before but I had noticed my gun sounded a bit "slow" when listenting to the pellet impact. Since my shots were consistently in the 126-128 m/s range (at 10m, not v0), and most of my competitors were 10-11 m/s higher than me, I decided to turn it up a bit. After that the puffing began.

I checked with the norwegian Steyr dealer, who was present at the championship, and he said this was completely normal and I shouldn't worry.

[Chia]

Okay if we're going to worry about this causing an accidental air discharge, I think we need a few more facts. Marc Orvin seems to believe that this is an accidental discharge, so we should probably proceed with a more serious analysis. I've got three ideas to look at.

First of all, IS air escaping? As in, is it coming out of the front of the barrel or another part of the gun? We've talked about the sound we hear but I don't think anyone in this thread has tried to figure out where the air is being "released." I don't know whether this requires just putting a piece of paper in front of the barrel or what, but I can't replicate the puff, so someone else needs to do this. This may matter if the rules in a sport about accidental discharge relate to air escaping from the barrel, for example.

Second, we need the definition of an accidental discharge with rule numbers. It sounds like we are speculating that an entire model of pistol is potentially unusable in some competitions due to accidental discharges. If we're going there, we definitely need to know what an accidental discharge is and under what discipline.

Third, I'd like to know if anyone has experience seeing users of the LP10 being sanctioned/punished for accidental discharges related to this "puff." The EVO is new, so we probably don't have much to go on there (if someone has experience great), but the mechanics inside are very, very close to the LP10. If this is a common issue with the LP10, then it is probably going to be an issue with the EVO. If not, the chances are less likely.

[David Levene]

Second, we need the definition of an accidental discharge with rule numbers.

6.11.2.1 If an athlete releases the propelling charge prior to the Preparation and Sighting Time he must be given a WARNING for the first violation and a DEDUCTION of two (2) points from the lowest value shot of the first MATCH series for the second and subsequent violations.

6.11.2.2 Any release of the propelling charge, after MATCH Firing starts, without a hit on the target will be scored as a miss. Dry firing without release of the propelling charge is permitted except during Finals.

The 2017 rules are much the same except they include the colour card that should be shown for a warning (yellow) or deduction (green)

[Gwhite]

Quibble for any experienced refs: If the gas released is just a small puff due to a quirk in the pistol, and not a full "propelling charge", is it a violation? Apparently a lot of Steyr's do this. If so, I'm surprised it hasn't come up at a big match.

Due to minor variations in manufacturing & wear, the Tau-7 dry fire adapters I make occasionally don't quite have enough clearance over the firing valve on some pistols. If that happens, you get a tiny "pop" when you dry fire. it is quite different from a full "propelling charge", but disconcerting none the less. Fortunately a little work on the adapter with a file solves the problem, and we haven't ever penalized anyone for it. The Tau shooters are usually beginning students who have enough issues without overly enthusiastic rules enforcement...

[DFWdude]

Well, sounds like I'm not the only one asking about this...
http://www.targettalk.org/viewtopic.php?f=4&t=53955

I suppose I can dial back the velocity on my LP10 to see if the behavior stops. But my LP1P doesn't have this issue, and it shoots 605fps where I like it.

[Mtl_Biker]

Apparently a lot of Steyr's do this. If so, I'm surprised it hasn't come up at a big match.

It does it on my EVO-10 and also with three other EVO's that are at my club. And I was told by my dealer that this is normal.

But I haven't seen anyone clarify this... You can dry-fire all you want, and this pfft (small discharge of air) ONLY HAPPENS if after dry-firing you CLOSE the cocking lever fully. It does NOT happen if after you finish dry-firing, you cock the gun again, load a pellet and fire, as would be the most usual scenario. And if you're only dry-firing and not in a match and want to fully close the cocking lever when you finish (without actually having fired a pellet) then the small pfft isn't an issue, is it?