Piston Spacer Washer(s) used how?

[Bogey]

Curious about how and in what circumstances  piston spacer washers would be used or applied.  What is thier purpose.  How are they used.  Do they cause any damage long term.
I have seen mention of spacers but without a clear meaning of why, how, where  or even when.
Appreciate your replies in advance.


Howie1a, did you ever get that .22 cal barrel from Crosman?  I am interested in knowing if it will bolt right on without any problems.  If it will I will place an order as soon as you give the results.

[shadow]

Polished washers are used inside the piston on some shooters and on the spring guide also. It gives the main spring a polished surface to ride and turn on and adds some weight inside the piston if wanted. I use them in some of my shooters if needed also Delrin washers are used. As far as the weight factor on the piston a little go's a long way, to much weight can create more problems. When I use them it's for a smooth ride for the piston and guide if needed there, not for weight. Ed

[Bogey]

Shadow,  does this create any significant  load on the spring ?  If you had to choose one to try first would it be in the piston or at the bottom of the guide for the spring?  I have not heard of the Delrin washers until now.  Where can they be found?

[shadow]

There can be a slight preload on the spring depending on the thickness of the washer. A thicker metal washer also means more weight piston wise, Delrin is a lighter material used in tunes for spring guides, tophat's etc. If you have a metal spring guide a good polish up would do the trick if you don't have the equipment to spin a nice fitting Delrin guide. Some spring guides are plastic and I've topped it off with a thin polished washer that fit's the guide nicely. If you want a smooth surface for your spring to ride on inside the piston then you want then material with very little weight, it depends on what your looking for. In need of a little extra punch in the piston then add some washers for weight but it should still be a polished surface and if your just wanted to smooth out the cycle of the shooter then keep it lite and polished. You can Google Delrin and there's dealers that sell the sticks of it in several length's.Ed

[shadow]

As I mentioned before when adding weight to the piston do it a little at first then assemble and check for any improvements with a chrony if you have one. Also when adding washers to the guide they should be the same diameter as the guide, to big of a washer or sometimes to thick will not let the sear engage and lock up properly on some airgun models. Ed

[Bogey]

Well this gives me something to think about.  Thanks for the well thought out answers / explanations to my questions. The caveat regarding interfering with sear engagement is a good heads up.

I figured if anyone could give meaningful answers promptly  it would be the GTA members on this forum.

Thanks

[shadow]

Always happy to help family and I'm sure that some of our other family will jump in with some good advice.:) Ed

[gamo2hammerli]

Yep....did the steel washer thing when I replaced the spring in my Crosman Sierra Pro.  Greedy dude that I am....I put a washer up front in the piston and one in the rear.  Put the gun all back together and the sear wouldn't catch!!!!!  Opened up the gun again and removed one washer.....put the spring back in and cocked the gun with the stock NOT on.  Still wouldn't catch so had to remove that 2nd washer also.  I think the washers that I had ordered from Jim Macarri were abit too thick.....oh well, maybe for another gun.

[speedturtle]

Piston washers used on Delrin guides:

Speedturtle

[howie1a]

I'm still waiting for it to come in I keep checking my bank to see if they pulled the money out for payment it's one way to know when it has been shipped, I'll post when it's here and done. howie

[Graham]

Washers are also used in tuning kits to fine adjust the power output. Here in the UK, you can break the law by using just one too many washers. The kit I recently installed in my HW35 had a rear guide and tophat, both fitted with delrin rotation washers. Also, in the kit were two power washers, one delrin, the other brass. With both installed, I was over our 12ft/lb limit, but by removing the brass one it dropped to 11.69ft/lbs.

[Bogey]

Want to thank one and all for your input.  Really helpful and without wild stories.  Surprised that one reply was from England from Graham.  Interesting that you chimed in but welcome.  We should hear from AG users from outside the U.S. more often to keep us up to date on Air gunning  issues in other countries. ( the sport and the politics of air gunning).

I can say that I know more now than before I asked.  Thanks.