Question about o-ring material

[Rivers3Plinker]

Just checking to see what materials others are using for o-rings on FT piston setups. I guess I should have checked here before ordering from McMaster. I bought 111 size Buna-n 70 duro. They are pretty cheap for a 100 count bag and I guess if they wear a little more quickly, I have plenty! I also bought some 90 for my valve per a suggestion I saw posted by Wyo man on another forum about building a pumper power plant. This is in a 13xx platform. Have to pin the valve next and eventually upgrade my barrel band pivot to a Chavka or Bluefork version.

TIA

[TimmyMac1]

THE BEST. This is what I use in the Mac1 Flat Head Piston Rebuild kit for old Crosmans and the Flat Head Piston Assembly for the 1322.

http://www.mac1airgunshop.com/ur-90-durometer-111-p/ms90ur111.htm
http://www.mac1airgunshop.com/flat-head-piston-for-early-crosmans-p/mflhepias.htm

TimmyMac1

[bgmcgee]

Got to agree with Tim.  He does have the best, all my pump guns use his o-rings and have never had a problem what so ever. They might seem pricey but how much is your time worth? One time install and done for a long time.

[DavidS]

I use 90 Duro O-Rings from harbor freight.  They work great, with out an extra hyped price.

[Roadworthy]

If you go to the O Ring Store (http://www.theoringstore.com/) they compare the properties of the various materials used for O Rings, as well as offering some incredible prices.

[Rivers3Plinker]

Thanks to all - gonna see how long the ones I bought last and burn through a few before I buy more.
Greatly appreciate responses though.
Oh...and lubing them with Mac1 secret sauce of course!
Giving my brother a custom 1322 carbine I built him for his 40th birthday today and including a bottle of it in the box : )

[bgmcgee]

Now that's a cool birthday present.

[DavidS]

Thanks to all - gonna see how long the ones I bought last and burn through a few before I buy more.
Greatly appreciate responses though.
Oh...and lubing them with Mac1 secret sauce of course!
Giving my brother a custom 1322 carbine I built him for his 40th birthday today and including a bottle of it in the box : )

Does your piston have an oil wiper?  If it does you will likely get more mileage just using 30WT ND oil on the wiper than you will using the secret sauce.   If it does not may I recommend making another piston that does have an oil wiper?

[Rivers3Plinker]

Thanks to all - gonna see how long the ones I bought last and burn through a few before I buy more.
Greatly appreciate responses though.
Oh...and lubing them with Mac1 secret sauce of course!
Giving my brother a custom 1322 carbine I built him for his 40th birthday today and including a bottle of it in the box : )

Does your piston have an oil wiper?  If it does you will likely get more mileage just using 30WT ND oil on the wiper than you will using the secret sauce.   If it does not may I recommend making another piston that does have an oil wiper?

Currently both of my guns lack oil wipers. These are pistons from AC Customs and I did not make them. I have been looking at adding an oil ring to the piston to reduce oiling maintenance. Is this what you're suggesting?

[bgmcgee]

I shoot the heck out of my 1320 with accustoms flat top set and just add a drop of oil every now and then. No need for a wiper .   Just oil a tiny amount every few 100 shots and you are good to go.

[Rivers3Plinker]

I shoot the heck out of my 1320 with accustoms flat top set and just add a drop of oil every now and then. No need for a wiper .   Just oil a tiny amount every few 100 shots and you are good to go.

Thanks Barry I appreciate the feedback. That's what I've been doing. It does make noticable difference in pumping smoothness and power particularly with 90 duro on the piston instead of 70. Wanna try a urethane O-ring instead of Buna now.

[D14Jeff]

i'm still using the 3 that came with my F/T P&V from ACCustoms . i'm gonna get some vitron 75s when i need more . here's a thread on CAPOF where i asked about the best o-rings for the 13xx based guns .

http://www.crosman-air-pistol-owners-forum.com/board/index.php/topic,12559.msg163499.html#msg163499

[Rivers3Plinker]

i'm still using the 3 that came with my F/T P&V from ACCustoms . i'm gonna get some vitron 75s when i need more . here's a thread on CAPOF where i asked about the best o-rings for the 13xx based guns .

http://www.crosman-air-pistol-owners-forum.com/board/index.php/topic,12559.msg163499.html#msg163499

I bought a bag of Buna-n 90's from McMaster primarily for the valve per Wyoman's thread on building pumper power plant. I put one on the piston of my 1322 as well and found that it pumps great but is a little jerky compared to the 70 duro that came with the piston kit from AC Customs. I would expect a 90 duro urethane to feel the same. Regardless, they were so cheap I have enough to last years and unless they let me make more power or the Buna material wears out so often it creates an inconvenience, I'm just going to stick with them for now. Need to stop putting more money into these guns!!!