Hammerli 152 circuit

[jacques b gros]

Hi!

Found an 152 in very good conditions in the metal parts, but with some reluctance to fire. Seems that the electronics are the problem.

Any chance of finding the diagram of that circuit?

Thanks

[Mike Taylor]

Not saying the electronics are not the problem, but did you check the solenoid plunger for free travel?
I purchased a used 152 and found it would not fire, but I discovered that the plunger (probably not the proper name, armature? - anyway, the moving part) would not move within the coil because the gap between the two parts was gummed up with dirt, combustion residue, and old oil. When I cleaned out the 'crud', so that the plunger moved freely, the pistol would then fire.

[jacques b gros]

Thanks for the tip. Did not fully check for lack of time, but will do.

[mister G]

Another thing easy to check out early on are the electrical contacts. I reconditioned a 152 that was reluctant to fire and luckily solved the problem basically by taking it apart, cleaning it and putting it back together. The oxide coating inhibits good electrical contact.

Use a pencil eraser gently.

[jacques b gros]

the moving part) would not move within the coil because the gap between the two parts was gummed up with dirt, combustion residue, and old oil. When I cleaned out the 'crud', so that the plunger moved freely, the pistol would then fire.

and from Mister G:
"Another thing easy to check out early on are the electrical contacts. I reconditioned a 152 that was reluctant to fire and luckily solved the problem basically by taking it apart, cleaning it and putting it back together. The oxide coating inhibits good electrical contact.

Use a pencil eraser gently."

Mike diagnosed perfectly and Mr. G complemented. It was hidden by crud, and the contacts were covered in lubricant residues. Used a liquid solvent to clean it.

One question: the solenoid plunger is pushed back down by the coking movement or mine has a broken internal spring and needs the movement to send it back down?

This is certainly the worst trigger design Hammerli ever put out. Could not find a way to dry fire, the battery is enormous (could use those small 12V) and will have to find a way to make the trigger position easier to adjust AND to fix it. Lousy piece of plastic won't stay in place.

Thanks for the tips. Now all I have to do is to re-learn to shoot this thing...

[Fred]

One question: the solenoid plunger is pushed back down by the coking movement or mine has a broken internal spring and needs the movement to send it back down?

This is certainly the worst trigger design Hammerli ever put out. Could not find a way to dry fire, the battery is enormous (could use those small 12V) and will have to find a way to make the trigger position easier to adjust AND to fix it. Lousy piece of plastic won't stay in place.

Jacques,

I no longer have my 152, and I never closely examined the solenoid. However if it is like the Morini 84e solenoid, the plunger should feel loose inside the coil and move freely up and down. I would guess that crud inside the solenoid is hampering that free movement. If the solenoid plunger moves freely, you should be able to dry fire without having to cock the action.

While the 9V battery is large, it is also relatively cheap and easily available, and will last a long time. Win some, lose some.

I found an excellent trigger blade solution for my 152. I obtained a Pardini trigger blade (used on the K58, K60, and earlier SP and MP models). The blade can be attached to one of the small threaded holes with a 2.5mm screw and washer. Its position can then be varied back and forth and it can be angled from one side to the other, just by loosening the screw.

HTH,
FredB

[jacques b gros]

Fred, thanks for the ideas. Will get back to the solenoid and see if I can clean it better.

As for the trigger blade, I think I'll trow Mr. C. Morini out of business: with the wire attachment piece of a light switch, an allen key (that came with the Hammerli 232 bought in 1975. Pistol sold, wrench sitll here) and the plastic blade of the 152 the problem is solved.

The small screw fits the gun, the large one fixes the allen key (will find a decent looking one tomorow) and the blade is firmer that it ever was. Can be moved back and forth and the blade can go up and down a bit, and tilt.

(did not try to buy the Morini set because, believe it or not, duties go to 93% if you import by mail. Over CIF. 60% federal, rest state taxes. They do want to make each one of us a smuggler...)

Thank you all.

[jacques b gros]

After cleanning the solenoid plunger with benzin (a very volatile petrol destilate) the thing went back to work, but only after cocking the pistol. The vibration of the movement sent the plunger down to its idle position.

Added some Molykote, the thing stuck.

With utmost care, removed the plunger height adjustement and removed the screw that fixes the solenoid to the frame. You cannot remove the solenoid due to the bunch of wiring, and the wiring is connected to a 20 or son pins socket that is glued to the frame.

But you can, with care, turn the solenoid around and remove the plunger.

Washed the plunger and the inside of the solenoid with benzin (is dry in seconds) and then added a lot more of moly, this time in the shaft only.


Thank you all for the help.

Still no dry shots, the plunger will not come down by gravity, but is working fine if you cock the thing.

[Fred]

Jacques,

I hope I didn't mislead you into extra work by my reference to the solenoid operation in the Morini 84e. Nevertheless, IF the 152 solenoid operates the same as the Morini one, there should be no lubrication on the plunger shaft. I had to replace the plunger on my 84e (broke in two!), and it was absolutely dry. Did you try the operation with the solenoid and plunger thoroughly cleaned and NOT lubricated at all? In that case, again IF it's the same as the 84e, the plunger should fall of its own weight, and not have to be pushed down by the cocking action. If the plunger does not move freely inside the solenoid after being thoroughly cleaned, there may be something binding it. Alternatively, is there any evidence of a return spring for the plunger?

HTH,
FredB

[jacques b gros]

Fred, don't worry about any extra work. You're trying to help, and that's what counts with me.

You're problably right, it has to be very clean. I put more moly for the simple reason that it was already messed with a few drops.

I think that the real problem is the sludge inside the solenoyd, at the top.
The dirt falls inside and is probably pressed hard against the top by the plunger, and is sticky.

This place is hard to clean, and the pistol is working now, but at the first failure I'll clean the whole thing and will polish the plunger.

Thanks

Good shooting

[J.Hoes]

In the early 2000's I shot a second hand, well used 152 for a short time. From what I recollect: I degreased the solenoid with cleaning fluid for video machines, and kept the thing dry. The core had a brass liner, so there was some dry lubrication. I am not shure if I could take out the plunger by removing the limiter bracket right under it.

The explosion drawing does not show a return spring. Dry firing will be the ticking of the solenoid.

Hans

[jacques b gros]

Hans,

to remove the plunger I had to remove the limiting bracket AND release the solenoid from the frame, which enabled me to rotate the set backwards and pull the plunger out.

You have to be extremely careful not to disturb that ridiculus amount of wires. If some of the lower tier wires gets loose it will next to impossible to reconnect the thing.

I'm no engineer, but I can draw many different setups for that mess that Hammerli did in the 152.

[womkiwi]

Hi!

Found an 152 in very good conditions in the metal parts, but with some reluctance to fire. Seems that the electronics are the problem.

Any chance of finding the diagram of that circuit?

Thanks

I know a fellow who has a 152 whose trigger circuit died. Hammerli is out of replacements and would have to build one from scratch, apparently, so he took it to an electronics whiz to reverse engineer it. The friend lost the circuit board before he could document it. So...

Did you have any luck finding the circuit diagram? This gun has none, and the owner was told "$1000US" to build a new one, when in reality there are probably about $20 worth of parts.

Cheers,
W

[jacques b gros]

Sorry to say that I found no diagram, Hammerli is gone in support and the documents are gone.

Heard a story that someone here in Brasil fixed one of them, after breaking apart the resin block that hides it.

Since the part is gone, maybe building another is not so difficult. I'm not capable of doing it, but the whole thing is made of 4 parts: the switch and leds, the movement sensor, the solenoid and the missing circuit board.

If you can find another 152 to measure the voltages and currents involved I think it would not be very difficult to build another.

Maybe the cost will make it impossible. As a general rule, I prefer mechanical machines, if made to last.

Good luck.

[womkiwi]

Oh well. Thanks for the reply. I'll chat with this owner and see if there are any options.
Walter

[VAshooter]

I have a 152 but I have never used it. I shoot a 150 and bought the 152 used as a spare.

I will bring my 152 in to work and check it to make sure it is working. I have the facilities to trouble shoot the circuit, reverse engineer it and build replacement circuit cards. If I remember correctly the wiring didn't impress me much either. I may be able to build a new harness for the pistol as well.

I'll post here with whatever progress we make.

VAshooter

[jacques b gros]

VAshooter,

If you could built another circuit board, why not maintain the wiring and the socket, so any other shooter with the same problem can solve it just by sticking a new board (made by you or on your specs) in the socket.

Good luck

[womkiwi]

I have a 152 but I have never used it. I shoot a 150 and bought the 152 used as a spare.

I will bring my 152 in to work and check it to make sure it is working. I have the facilities to trouble shoot the circuit, reverse engineer it and build replacement circuit cards. If I remember correctly the wiring didn't impress me much either. I may be able to build a new harness for the pistol as well.

I'll post here with whatever progress we make.

VAshooter

Hi VAshooter,
Had any luck sorting out what the circuits are?
Cheers,
Walter

[FFR77]

Hello all,

I would be interested in any news concerning the board or circuit as well. Mine seems to have developed a capacitor problem over time.

Cheers,

Franz

[SamEEE]

Holy necropost.

Caps have a usual rated life. You could pretty easily get it replaced with a nice new one.
I have never seen a 152 board, can you post some detailed photographs?

If new caps don't fix it then it might need a 'reflow'.
Odds are you could take it to a vet/dentist with beer money to have the board xrayed, and then reverse engineer a new one.