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Airguns by Make and Model => Crosman Airguns => Topic started by: basednibbba on January 04, 2020, 02:54:18 AM

Title: quick take-down pin
Post by: basednibbba on January 04, 2020, 02:54:18 AM
I am interested in modifying a crosman 1322 to be suitable for the role that a gun like the henry AR-7, Armalyte M4, or Ruger 10-22 take-down would usually fullfill (that of a survival rifle). Unfortunately, the crosman can only be practically broken down into two peices (stock and receiver+barrel). Nevertheless, I decided to make a pump pivot secured with a wingnut that can be removed with nothing but five fingers. I am happy with it so far, but only time will tell. I have noticed that the aftermarket pins only really use either two screws, two o-rings, or two e-clips to secure the pin, so I am sure there must be a reason why people arent using wing nuts? The disadvanteges of my pin that I can think of are:the threads may abrade during the removal and installation process. The wingnut may not provide enough tension to resist loosening during operation. The wingnuts tightening against the pump tube abrades the tubes rust resistant black finish. Please enlighten me to any other deficiencies this design may have. The pin itself is constructed of 3/16" cold rolled steel rod. I would have preffered something tougher, but I was worried that the set of princess auto dies I own would be ruined if used on something harder. The wing nut and acorn nut are 10-24 thread and were initially galvanized. I stripped the galvanization with a vinegar bath that lasted about 30 hours. I then treated each part of the pin assembly with a oil blackening process. Just heated the parts up until just below red hot, then dumped them in some motor oil. I aimed for 1.248" for the length of the pin, but I settled for about 1.27". One thread is protruding beyond the wingnut, as well as the tip of the pin. I cut five threads for the wingnut side and about seven threads for the acorn nut side. I put red loctite on the acorn nut side to create a sort of acorn headed bolt. If you are like me and have no other machine tools than a crappy princess auto 8-inch drill press I would suggest you cut with generous tolerance and sort of hand fit with hand files and do one thread at a time till you achieve enough tension (what I ended up doing). If any of you are interested, I would be more than happy to elaborate a bit on the process. Thanks for reading.
Title: Re: quick take-down pin
Post by: Airgunnr88 on January 04, 2020, 11:38:17 AM
Maybe I'm missing something, but I don't see the point of taking the pump arm or any of the pump mechanism off.  It doesn't really make it more compact, and if you take the piston out it could easily become damaged.  Or dirt could get stuck to it or get inside the tube and foul things up.

Just removing the stock makes it a lot more compact and easily able to fit in a backpack or even something like a messenger bag.  I've been thinking about making a simple quick-detach setup with a few loops of shock cord that fit snugly around the protuberance at the bottom of the grip enough to hold the stock on, but able to be removed or reattached without messing with screws and a screwdriver.
Title: Re: quick take-down pin
Post by: Robert 5mm on January 04, 2020, 12:49:41 PM
The Crosman Bug Out 1322 does not have any screws in the grip handle, just a pin you push in at the top to remove the stock.

https://www.pyramydair.com/product/crosman-doomsday-bug-out-air-rifle-kit?m=2913 (https://www.pyramydair.com/product/crosman-doomsday-bug-out-air-rifle-kit?m=2913)
Title: Re: quick take-down pin
Post by: basednibbba on January 04, 2020, 01:33:13 PM
Maybe I'm missing something, but I don't see the point of taking the pump arm or any of the pump mechanism off.  It doesn't really make it more compact, and if you take the piston out it could easily become damaged.  Or dirt could get stuck to it or get inside the tube and foul things up. Just removing the stock makes it a lot more compact and easily able to fit in a backpack or even something like a messenger bag.  I've been thinking about making a simple quick-detach setup with a few loops of shock cord that fit snugly around the protuberance at the bottom of the grip enough to hold the stock on, but able to be removed or reattached without messing with screws and a screwdriver.

You’re right. The pin isn’t helpful in making the gun more compact, but it will make it a bit easier to maintain the valve, piston etc. I will no longer need a hammer and punch to gain access to those parts.

 If I wanted to make the gun as short as possible, I would have to remove the barrel from the pump tube, but then there would be a whole bunch of small parts like the transfer port poppet and transfer port seal and so on.
Title: Re: quick take-down pin
Post by: Airgunnr88 on January 04, 2020, 05:13:05 PM
Good point, I guess being able to get to the piston easily for maintenance would be a good feature for a survival gun.  I was thinking the wingnut was intended as part of the "take-down" feature for transporting it.

I just ordered one of the replacements with allen screws on the ends for mine, $9 shipped on Ebay.  Best price I was able to find for one.  I'm not able to post a link, but the seller is "accurateiair."  Not as handy as a wingnut since you still need some kind of driver or wrench, but better than that nasty roll pin.