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Thread: Scorpion pistol trigger reassembly etc

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    Scorpion pistol trigger reassembly etc

    I have recently been playing (!) with a BSA Scorpion pistol that was in a very sorry state: the piston had seized in the cylinder, the buffer washer on the piston had disintegrated, there was no safety spring and the trigger assembly was clearly wrong.
    Stripping the Scorpion has been covered by Guy (ggggr) in the excellent 'Idiot's Guide' sticky on this forum so I will not go into that part, but I failed to find instructions on how the trigger goes together .. and thanks are due here to Troubledshooter for his help with pictures showing how the safety spring fits and to Guy for his helpful comments as I battled with my pistol.
    So ... lets assume you have stripped the pistol, the safety catch lever is removed (it has to come off to strip the pistol), you have split the trigger housing from the cylinder and for whatever reason want to remove the trigger/sear parts. First thing: think about it! Do you really need to do this? It is not easy ... you may get it done in a few minutes, you may sweat away for hours to get the bits back correctly. Assuming you want to do it: With a small punch or screwdriver push out the pin that holds the sears inside the housing. There is no need to remove the trigger itself unless you want to and if you do, just push out the trigger pivot pin and it comes away quite easily ... take care not to lose the spring in the trigger blade. The trigger bar will separate from the trigger ... it goes back 'straight side' up towards the cylinder.
    With the sears pin out and your prod removed, the bits will fall apart .. you will have the pivot pin, a spacing washer, a spring, a small sear and the hammer (bigger bit). Once removed, the safety can be removed.Chambers show an exploded diagram.
    Now, before trying to assemble the bits, make a 'slave pin' the same diameter as the pivot pin and just long enough to fit snuggly between the sides of the trigger housing. Without this you may as well give up. I made mine from a nail.
    Step 1: fit trigger, if you removed it, and insert the safety bar and fit the catch lever. Get some fine wire and put it through the hole that the safety spring locates in. This is all to stop the catch falling out as you fiddle with the other bits.
    Step 2: Hold your slave pin and add the hammer with the long prong pointing away from you and the small peg on the hammer on the underside, the hammer notches will be to the left. Add the small sear from underneath with its longer end away from you and bending towards the right... arrange it so that the right hand edge of the sear fits against the lhs of the peg on the hammer. Add the washer on top of the hammer. Fit the spring: the hooked end goes around the base of the hammer and the simple bent end needs to be fitted so that it rests on the left hand edge of the small sear. This is fiddly as it has a tendency to slip off. Now, holding all this together between finger and thumb, insert it into the trigger housing from the top and to the right of the trigger bar. The hammer long prong will be upwards and will be close to you. Carefully slide it down ... the long tang on the hammer is good for this. Take care that the spring end does not ping off the edge of the small sear. If it does, start again. Keep wiggling the assembly down and towards the trigger bar. You will reach a point when you must take care that the sears are going to fit inside the cut out on the safety bar. Keep wiggling, with help from a small screwdriver, until you can see your slave pin next to the holes in the housing that the sear pivot pin goes it. This can be fun. Take the pivot pin and hold it in the housing hole next to the washer. Keep fiddling with the position of your slave pin until the true pin can be pushed in. It helps to keep the hammer at its 'at rest position' with regard to the trigger bar i.e. trigger bar on top of the first notch of the hammer. You may achieve a perfect push first time ... more likely you will get your pin through the washer but then have to continue jiggling until it pushes the slave pin all the way out. Job done. Sounds easy! Check for working ... you can cock the trigger by pushing the long arm of the hammer down to the right. It cocks onto the second notch. Check action with safety spring fitted. I found it easier to remove the long sear from the trigger housing to do the sear assembly, it can flap around otherwise or may even fall off if the pin comes out. If you removed it, refit it now and if all is well, refit housing to the action.
    Hopefully all will be well but I know from experience that the safety catch can be temperamental .....
    Cheers, Phil

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    Exclamation Scorpion

    I think the advice about thinking about it is very good. I did not want to attempt to put a trigger strip in the "idiots guide". I did 3 scorpion triggers just before Christmas and they were fun It did not help that the safety bars that I bought from Chambers were supposed to be for the non automatic safety and they turned out to be the automatic ones. I actually found 2 ways to make the safety non automatic.
    used slave pins on quite a few guns. The short pin idea works very well with the Baikal IJ 38 but I never actually thought of it for the Scorpion . I just use a pin punch and push it through the housing a bit at a time as each piece goes onto it. A small screwdriver or tweezers/small long nose pliers can help. One other thing I found out, which I think I did mention in the idiots guide (but not looking to check) is that you can sneak in an extra small,thin plain washer on the outside (RHS) of the hammer spring. This makes the thing a bit more positive.
    I love these pistols but I think a simple long sear,short trigger set up with a coil spring would have been better,easier and cheaper.
    THREAD HIJACK--- on the look out for a complete trigger set up for a scorpion so please bear this in mind when you start to take yours apart.
    Cooler than Mace Windu with a FRO, walking into Members Only and saying "Bitches, be cool"

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    Quote Originally Posted by ggggr View Post
    THREAD HIJACK--- on the look out for a complete trigger set up for a scorpion so please bear this in mind when you start to take yours apart.
    I wouldn't think you'd wait too long, I imagine there to be many Scorpions that are slowly rusting in lofts, after amateur curiosity of the "inner workings", resulted in a permanent premature state of perpetual disassembly

    Good on the OP for the effort of writing that up

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    Scorpion trigger update

    An extra thought: When you have got the trigger together again and assuming you are still sane you may look at it and wonder if it is correct. You may notice that when uncocked, you can move the long leg of the hammer to the right (looking down into the housing, hammer towards you) for one notch on the hammer and nothing seems to happen except the hammer and spring assembly moves: there is no spring tension. Only after the trigger bar has set on the first hammer notch does a further push on the long leg act on the hammer spring and the hammer cocks on the second notch. Never having seen a Scorpion trigger before I spent ages puzzling over this, wondering if something was wrong and if there should be spring tension from the very first movement. But 'no' .. there is no tension until the sears unit has moved to the right one notch; the small sear then catches on the underside of the safety bar and extra movement of the hammer is against spring tension from the hammer spring. Releasing the trigger allows the hammer to fly backwards, the tiny spiggot on the hammer then clouts the small sear and both hammer and small sear move back to rest, releasing the long sear that holds the piston and firing the shot.

    I note Guy is seeking Scorpion trigger parts. I would like to find another hammer piece if anyone has a scrap unit..... but please give Guy priority.

    Cheers, Phil

    PS I made a 'cocking aid' from some 15mm id plastic tube ... cutting a slot 10mm wide x 11cm long to fit over the barrel and foresight. It certainly saves on a bruised palm.

  5. #5
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    If the bits in a re-assembled trigger unit appear the same as those in my pictures, you shouldn't have a problem.

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    Quote Originally Posted by Phil Russell View Post
    I have recently been playing (!) with a BSA Scorpion pistol that was in a very sorry state: the piston had seized in the cylinder, the buffer washer on the piston had disintegrated, there was no safety spring and the trigger assembly was clearly wrong.
    Stripping the Scorpion has been covered by Guy (ggggr) in the excellent 'Idiot's Guide' sticky on this forum so I will not go into that part, but I failed to find instructions on how the trigger goes together .. and thanks are due here to Troubledshooter for his help with pictures showing how the safety spring fits and to Guy for his helpful comments as I battled with my pistol.
    So ... lets assume you have stripped the pistol, the safety catch lever is removed (it has to come off to strip the pistol), you have split the trigger housing from the cylinder and for whatever reason want to remove the trigger/sear parts. First thing: think about it! Do you really need to do this? It is not easy ... you may get it done in a few minutes, you may sweat away for hours to get the bits back correctly. Assuming you want to do it: With a small punch or screwdriver push out the pin that holds the sears inside the housing. There is no need to remove the trigger itself unless you want to and if you do, just push out the trigger pivot pin and it comes away quite easily ... take care not to lose the spring in the trigger blade. The trigger bar will separate from the trigger ... it goes back 'straight side' up towards the cylinder.
    With the sears pin out and your prod removed, the bits will fall apart .. you will have the pivot pin, a spacing washer, a spring, a small sear and the hammer (bigger bit). Once removed, the safety can be removed.Chambers show an exploded diagram.
    Now, before trying to assemble the bits, make a 'slave pin' the same diameter as the pivot pin and just long enough to fit snuggly between the sides of the trigger housing. Without this you may as well give up. I made mine from a nail.
    Step 1: fit trigger, if you removed it, and insert the safety bar and fit the catch lever. Get some fine wire and put it through the hole that the safety spring locates in. This is all to stop the catch falling out as you fiddle with the other bits.
    Step 2: Hold your slave pin and add the hammer with the long prong pointing away from you and the small peg on the hammer on the underside, the hammer notches will be to the left. Add the small sear from underneath with its longer end away from you and bending towards the right... arrange it so that the right hand edge of the sear fits against the lhs of the peg on the hammer. Add the washer on top of the hammer. Fit the spring: the hooked end goes around the base of the hammer and the simple bent end needs to be fitted so that it rests on the left hand edge of the small sear. This is fiddly as it has a tendency to slip off. Now, holding all this together between finger and thumb, insert it into the trigger housing from the top and to the right of the trigger bar. The hammer long prong will be upwards and will be close to you. Carefully slide it down ... the long tang on the hammer is good for this. Take care that the spring end does not ping off the edge of the small sear. If it does, start again. Keep wiggling the assembly down and towards the trigger bar. You will reach a point when you must take care that the sears are going to fit inside the cut out on the safety bar. Keep wiggling, with help from a small screwdriver, until you can see your slave pin next to the holes in the housing that the sear pivot pin goes it. This can be fun. Take the pivot pin and hold it in the housing hole next to the washer. Keep fiddling with the position of your slave pin until the true pin can be pushed in. It helps to keep the hammer at its 'at rest position' with regard to the trigger bar i.e. trigger bar on top of the first notch of the hammer. You may achieve a perfect push first time ... more likely you will get your pin through the washer but then have to continue jiggling until it pushes the slave pin all the way out. Job done. Sounds easy! Check for working ... you can cock the trigger by pushing the long arm of the hammer down to the right. It cocks onto the second notch. Check action with safety spring fitted. I found it easier to remove the long sear from the trigger housing to do the sear assembly, it can flap around otherwise or may even fall off if the pin comes out. If you removed it, refit it now and if all is well, refit housing to the action.
    Hopefully all will be well but I know from experience that the safety catch can be temperamental .....
    Cheers, Phil
    Well I managed to do all this without throwing it all in the bin out of frustration !!
    You are right about the safety catch now being a bit temperamental BUT my biggest issue is the hammer sear works perfect when the trigger assy is not mounted back on the barrel but sticks when the trigger is pressed when screwed back onto the barrel. I have followed the reassembly guide and tied the main sear down when remounting the trigger assy but the hammer still sticks very slightly when the triggers is pressed. The slightest of prods by a terminal screw driver to the back of the hammer and it slams down perfectly.

    video of the trigger assy working as it should when removed from the barrel can be viewed here

    Hopefully I can bottom this out with the help from others who have fought this complex trigger assy in the past.

    Andy

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    Does the hammer sear rest of the side of the trigger housing?
    The hammer sear sticks very slightly when screwed back onto the barrel but works perfectly when the assy is removed from the barrel.
    There is also no wear/movement marks left by the hammer sear on the trigger housing.

    Example video here

    Close but yet so far with this trigger unit

    Andy

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    Quote Originally Posted by aabs View Post
    Well I managed to do all this without throwing it all in the bin out of frustration !!
    You are right about the safety catch now being a bit temperamental BUT my biggest issue is the hammer sear works perfect when the trigger assy is not mounted back on the barrel but sticks when the trigger is pressed when screwed back onto the barrel. I have followed the reassembly guide and tied the main sear down when remounting the trigger assy but the hammer still sticks very slightly when the triggers is pressed. The slightest of prods by a terminal screw driver to the back of the hammer and it slams down perfectly.

    video of the trigger assy working as it should when removed from the barrel can be viewed here

    Hopefully I can bottom this out with the help from others who have fought this complex trigger assy in the past.

    Andy
    Hi Andy---I've looked at your video in slow mo on you tube. I may be wrong, but to me the hammer looks bent at the top where the the cocking arm pushes on it. It should be cranked out but not bent backwards. Have a look here http://www.airgunspares.com/store/pr...t-No.-16-3153/ or see if there are some pics up on the bbs. I think Troubled shooter did some but not sure if they have been lost when Photo bucket played up.

    If you use a small screwdriver to pull the sear back you will hear 2 distinct clicks as the trigger bar drops into the steps on the hammer. If you pull the trigger then the hammer should go forward and knock the little sear forward.

    On mine, the hammer was bent backwards and I didnt have one to compare it to. Eventually I got one and noticed it was ben back , so heated it up and straightened it. IF it is bent backwards , then when the cocking arm pushes on it to set the trigger, the hammer only goes to position one and not position 2, so the trigger spring cannot fire it forward with enough momentum to knock the little sear.

    I am only assuming your hammer is bent backwards off the video. If it is not that then a phone call is easier than typing out all the options.
    Last edited by ggggr; 27-05-2020 at 11:27 AM.
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    These are the photographs Guy is referring to; unfortunately they disappeared from my net Images site when they pulled the plug, and I haven't created another site.



    ]url=https://postimg.cc/bsTzWyk8][/url]






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    Yeah thanks, these are what I've been working off.
    I must be mad as I've had this trigger assy apart more than any sane person would imagine.
    I think guy maybe correct that the hammer sear is slightly bent but I cannot find stock of the hammer sear.
    Thanks for the help

  11. #11
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    Thanks for the help guys,
    I do have the two clicks just a little drag holding back the hammer sear.
    Removed the hammer sear and close inspection does show stress marks to the metal.
    I heated up and bent the hammer sear forward a little where the stress marks were.
    Issue is still the same aarrghhh

    Just got to find a replacement hammer sear if anyone has one in a box of bits or a link to any stock

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    Well thanks to the help of the good guys on this forum. I have now managed to save another scorpion trigger assy from landfill.
    Special mention to ggggr who correctly identified that my hammer sear was not reaching correct position when cocked on barrel.
    Compared my hammer sear postion with postion of hammer sear on troubledshooters topview distcharged image.
    Couple of rough images to show where my hammer sear was in RED and where I moved it to in GREEN.
    My GREEN position is a little more advanced than troubledshooter image but its no fun rebuilding the scorpion trigger so wanted to make sure but not go too far to break the sear.
    My trigger assy now works perfectly with auto safety action as it should be when cocked.



    https://postimg.cc/gallery/w1jK9p0

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    Quote Originally Posted by aabs View Post
    Well thanks to the help of the good guys on this forum. I have now managed to save another scorpion trigger assy from landfill.
    Special mention to ggggr who correctly identified that my hammer sear was not reaching correct position when cocked on barrel.
    Compared my hammer sear postion with postion of hammer sear on troubledshooters topview distcharged image.
    Couple of rough images to show where my hammer sear was in RED and where I moved it to in GREEN.
    My GREEN position is a little more advanced than troubledshooter image but its no fun rebuilding the scorpion trigger so wanted to make sure but not go too far to break the sear.
    My trigger assy now works perfectly with auto safety action as it should be when cocked.



    https://postimg.cc/gallery/w1jK9p0
    Pleased you sorted it Andy That was the problem I had with the first Scorpion I ever got. The good news is that the rebent hammer is still working 11 or so years on..
    I'm happy (wrong word with Scorpions) to chat on the phone about Scorpions but it is a bugger trying to explain how/ what on here or by Pm.
    I think I've managed to help 7 people on here with Scorpion Triggers in the last few years, by phone or message. Of those, 4 have just been the safety spring tang needing a tiny tweek.
    Cooler than Mace Windu with a FRO, walking into Members Only and saying "Bitches, be cool"

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    Quote Originally Posted by Troubledshooter View Post
    These are the photographs Guy is referring to; unfortunately they disappeared from my net Images site when they pulled the plug, and I haven't created another site.
    As you may recall, David, I created a replacement site using all the images of yours that I had on file (with your blessing). If you have any others you want me to add, please send them over.

    https://forum.vintageairgunsgallery....shooters-pics/
    Vintage Airguns Gallery
    ..Above link posted with permission from Gareth W-B
    In British slang an anorak is a person who has a very strong interest in niche subjects.

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