Sunday, July 28, 2013

Crosman 766

I have had most of a Crosman 766 sitting on a shelf waiting to be put together for a year or more. At one point I had a list of the missing parts but never got around to ordering them. This weekend I dusted off the parts and put together another list. I need some other parts for another project that is on its way so I should actually get parts ordered this time.

There are three variants of the 766, the first version had a tapered plastic barrel housing. The second variant had a tapered metal barrel housing and the third variant had a straight metal barrel housing. The third version was renamed and became the 2100 in 1983.
My rifle is the second variant of the 766. Parts are no longer available from Crosman as they quit making this version of the 766 in 1981. I am ordering parts from the parts list for a late model 2100. A lot of the parts for the 2100 have a 766 prefix, it was nice of Crosman to continue to use the same parts through the years otherwise it would be much more difficult to find the parts I need. There are some differences, most of which seem to be to make production easier and cheaper. I'm not saying the 766 is better than the 2100 just that the 2100 is less expensive to make and the reason you can get a 600+ fps pumper that will put pellets inside a dime at 10 yards for around $60.

There were enough parts to bolt together to make sure it was shootable and it has turned out to be a good shooter so far.


I shot this group at 10 yards, from a bench rest with iron sights. Close to dime sized... not bad.

The missing parts are for the BBs, and the detent that holds the pump arm in the closed position. Being able to shoot BBs isn't important to me but it might be to the next owner so I want to replace them. I replaced the pump seal with a new one and for now the pump arm stays in the closed position.

I cleaned up the valve first, I got lucky and everything looked good and works well. I replaced the O-rings while it was apart.

I used a wooden dowel to push the valve into the pump tube making sure the exhaust port on the valve was lined up with the corresponding hole in the pump tube. The pump got a new pump cup.

I slid the pump into the tube and pressed the pivot pin in place. 

Here are the breech, bolt and BB magazine.

The parts assembled and installed in the receiver half, one of the few differences from the 2100 is the screw that holds the breech in place.

The hammer, hammer spring and plug. 

Getting all of those pieces  assembled and into the receiver half is the most challenging part of this reassembly. It can be very frustrating and take a few tries but it will all fit together, a certain amount of colorful language is required. If you don't cuss, you may start after trying to put one of these back together.

Another difference from the 2100 is the sear, however the trigger is the same for both the 2100 and 766. 


Once I get the missing parts I will tear the 766 apart again for a final clean up and reassembly. It is in pretty good shape for a 30 year old air gun.... actually it is in damn good shape for its age. 


  







40 comments:

  1. How did you pull the valve apart? I can't unscrew the top of it, and I'm wondering if I'm missing something. Thanks.

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  2. Most of them have Loctite on the threads. I use pliers to grip the end where the O-ring is, if it is really stubborn I use a second set of pliers to grab the other half too. The end with the O-ring is pretty fragile so you need to be careful with the pliers. I have a piece of leather I use as a cushion for the jaws of the pliers. If you get some nicks in the valve they can be filed and smoothed out. If it is really stubborn you can try a little heat to soften up the Loctite. Good luck!

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  3. Where are you getting the parts?

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    1. I have accumulated a stash of parts, most came from an online auction that I won a few years ago. A box of about 20 used air guns. I repaired most of them and sold them to cover my costs. Anything that couldn't be repaired was stripped for parts.
      The nice thing with Crosman is a lot of the parts interchange. The 766 is a good example. After a few changes the 766 became the 2100 and some of the parts interchange between the two. So you can still get some parts from Crosman that will fit a 766..

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  4. Hi Rick, I took my valve out and I really cannot make out where the two halves meet, I know is a dumb question but I'm having a real challenge here.
    Thanks

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  5. The 5th picture shows the valve disassembled, it splits just behind the o-ring.

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  6. Hi there,
    I also have a crosman 766 which I acquired off my father however there is a part broken which I am seeking and it appears very difficult to find on the internet. The part is the aluminium breech which you show in photos 8 and 9 and refer to it as the difference with the "2100 is the screw that holds the breech in place". I am wondering if you have any of these left which you might be willing to part with or know of where I can get them.
    Cheers

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    1. The first generation 766 are the only ones with that style of breech. I have had a couple of them so they are still out there. I no longer have any 766 rifles or parts. Your best bet is to ask around the air gun forums, hopefully someone has a spare. Best of luck with your search!

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  7. Hi Rick,
    I have a crosman 766 which I bought in 1976. I believe that it is the first model (tapered plastic barrel). The gun is in excellent condition only does not hold air pressure for more than a few seconds. I have disassembled the valve and am pretty sure the problem is the leather seal inside of the valve. Do you know where I can get a replacement seal for this gun? Also is the valve on the 2100 the same as in my 766?
    Thanks.

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    1. If you haven't tried Crosman Pellgun oil, I would try that first. Sometimes the oil will give new life to a failing seal. The 2100 valve is very similar to the 766 valve. In the past I have swapped parts between the valves, Crosman was very good about using the same parts in several different models. I would give Crosman a call, and see if parts are still available.

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  8. Rick, I just rebuilt the air cylinder in my 766 Crosman which I think went ok. I bought this rebuild kit from Alliance Hobby's. My question is it normal after I pump it up 10 times and fire it once with a pellet or no pellet that there is still a lot of compressed air still in the air cylinder after I re-cock the gun and pull the trigger? Vern

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    1. Having air left in the valve after only 10 pumps isn't normal. My first thought is the striker/ hammer spring is weak and not opening the exhaust valve far enough or holding it open long enough. If the valve rebuild went well the striker is where I would start. Make sure the pin on the striker is not hanging up in the bolt and that the striker is able to move freely in the tube. The only other thing that I can think of is that the check valve spring is too stiff and it isn't letting the valve open like it should. If you have to open the valve up check to make sure that stem on the exhaust valve moves freely in the valve body. I hope this helps. Rick

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    2. Rick thanks for the fast reply to my question. The spring that came with the repair kit was and is somewhat stronger than the original one that was in the what I call the air cylinder which is made of brass. Is that the spring you referred to as the check valve spring? Vern

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    3. Mr. Rick, I removed the spring that came with the rebuild kit and put the original spring back in the brass air cylinder which now after pumping 10 times and cocking and firing the gun there is very little if any compressed air left in the air valve, so it looks what you said that check valve spring was too strong and not letting the valve open enuf... Thanks, Vern

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    4. Glad you got it repaired! Happy shooting!
      Rick

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  9. I've had my 766 since 1980 and after several years in the loft still works fine. The fore stock has the usual wear that means it won't stay shut. I bought the gun from Sussex Armoury who claimed they converted it to take 18 pumps at 860 fps. Shot loads of rabbits with it and found it deadly accurate. I gave it that today and got a 2" group at 30 yards with a 37 year old scope. Not sure about the power but would love to restore and get a new fore stock. Any advice?

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    1. Crosman is your best bet for parts. Some of the model 2100 parts will interchange. On the later 766s I rebuilt the forestocks interchanged with 2100, I can't say that is still the case though. I haven't done anything with airguns for several years now. I would tear it down and clean everything up, replace the o-rings on the exhaust valve and if it still has the stock pump cup replace that. Have fun!

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  10. This comment has been removed by the author.

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  11. Rick, I have a borrowed 2100 that didn't hold any air pressure and would just "click" when fired, without firing the pellet. I ordered the new O rings and pump cup and rebuilt the the cylinder, but still, just a "click" when fired. I'm getting good at re-assembly, but I'm stumped, any advice?
    thanks,
    Mike McKenney

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    1. The 2100 can be a juggling act to get back together. A few thoughts, 1) Are you sure the valve is holding air? Does it get harder to pump the more you pump it? 2) There could be to much air pressure in the valve and the hammer doesn't have enough power to overcome the air pressure.
      If you feel resistance when pumping then I suspect #2 and you are going to have to open it up again. To check to see if the valve is holding air I use a wood dowel that will reach in the tube from the rear and tap it with a hammer to release the air. While you have it apart check to make sure the hammer slides free and hits the exhaust valve, take a look at the spring... Look for anything that could keep the hammer from hitting the valve hard enough to open it.
      If there isn't much or no resistance while you pump it up it's either the pump cup or the valve. You can put the muzzle under water and work the pump (make sure the bolt is closed) if it blows bubbles out the end of the barrel the valve is leaking the air out and needs to be looked at (bad exhaust valve or check valve). No bubbles would point towards a bad pump cup.
      These are the first things that come to mind, hope it helps.

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  13. i found this a crosman 766 at my grandparents and know nothing about it and when i took it apart i could not get it back together correctly. the reason i took it apart was the little spring on the side with the little black piece that you pull back before you can shoot broke and i think a few springs were missing any advice on where i can take it to get it fixed / for new part ?

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    1. Crosman will be your best bet for finding parts, even though the 766 has been in production for many years it shares many parts with the 2100. You could also check out some of the airgun forums for more help.

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    2. This should read "the 766 has been out of production for many years"

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  14. Hi there Rick
    I've got a phase 1 766 (tapered barrel) that suddenly wouldn't hold air. I fitted replacement O rings on the valve assembly and it worked great again for about 5 shots then suddenly wouldn't hold air again. This time I could hear air whooshing out the barrel with each pump. I Googled that and found mention of that meaning the valve stem was faulty. I'm in the UK and parts are hard to get without breaking the bank. Is there any kind of fix for the valve stem or is it replace only? Thank you and best wishes. Jake

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    1. Jake,
      Unfortunately there aren't any easy fixes for a worn out valve stem. I would try cleaning and oiling the valve stem, check the sealing surface for any nicks or wear. Make sure the spring is in good shape. I would check the airgun forums you might be able to find someone with parts you need. Good luck!

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    2. Thank you very much indeed, Rick. Appreciate your advice. Jake

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  15. Hello,
    Do you still have any 766 parts left?
    I need a stock.
    thanks
    mike

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    1. Sorry it took so long to answer but no I don't have any 766 parts left. I've been out of the hobby for several years now. I just leave the blog up in case people find some of the pics and info useful.

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  16. Hi Rick,
    I am rebuilding my grandfather's Crosman Phase I 766 (thanks for the information you have already posted above). It took heat and leather padded plier jaws to get the valve apart. Is it really LocTite on the valve body threads or just a thread sealant?

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    1. I'm not really sure if it's LocTite on the valve, sealant makes more sense. When I reassembled the valves in my air guns I put them together with out either loctite or sealant, never had a problem.

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  17. I have a Crossman 766 serial #076430237 that the breech is solid Aluminium and the Gas tube is molded to the Breech. It has no writing on the side covers & only the lower tube is marked with the model. Have you ever seen this & how does the gas tube come apart, I don't want to mar or bend it.

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    1. I think you have the same one that I have. I have identified it as a 766 Phase 1. I call it the "Receiver" (I think you are calling it the breech) that is all aluminum and it seems to have the brass valve pressed into the aluminum. I damaged the valve cap unscrewing it, knowing that I had an aluminum on in my repair kit. I have all of the dried grease cleaned out of the valve and am questioning using the parts that were in it or the new parts in the kit. It seems people don't use grease or oil on reassembly... wish me luck.

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  18. I'm not real sure what you are asking, along with the fact that I haven't torn into a 766 for many years. I would suggest you find a forum or blog that is more active than mine to get your questions answered. I don't want to lead you down the wrong path and cause damage to your air gun. There is a facebook page dedicated to pumpers with some good guys who should be able to help you out. https://www.facebook.com/groups/207795509609612/?ref=bookmarks

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  19. I aquired an excellent in near NEW condition Crosman 766 serial # 579220119 with a fairly good box, hand printed in blue ink "Display" on the front of the box & tiny hole in the back where the cocking handle protruded... even has the original reciept 45.27 & 2.57 tax(cant make out the store purchased from or date..theres a hole in the middle of the reciept & cant make out 2 more lines of prices(might be for the vintage Busnell Sportview 4x15mm Riflescope..From what I've read here this may be the 2nd varient with the tapered metal barrel housing...one tiny mark on the left side of the reciever & a small white spot of paint? on the rear botton butt stock, other than that, it look excellent, unfired/fired??? who knows.. if it was not much..The lower part of the barrel is turning, what Id call a little PLUM (between the barrel band & reciever) Anyone interested??

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  20. Any takers on this yet? If not, how much do you want for it?

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  21. Does anyone know if the stock for the Crossman 2100 will fit the Crossman 766? Or does anyone have a source for a 766 stock? Thank you

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    1. It has been several years since I replaced one, but the last time I did it the 2100 stock was a direct replacement for the 766 stock.

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    2. Thank you, will give it a try.

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