Hi all, I was just wondering which type of O-rings you guys use and think are the best, I think the buna-N (nitrile) for all-around, post up!

Urethane are the most durable. They're more expensive, though. That's why the buna-n are all the rage now. They're cheap (almost half the price usually), and prevalent in lots of o-ring packages. Too bad you usually go through twice as many as compared to urethane.

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How To: Paint a V-Force Grill Multicam | My E-Tac (work in progress)

These have been my findings based on my own experience and findings on the web.

Buna-N (Nitrile):

Temperature Range: -22F - 212F

Pros:

• Excellent compression
• Good Tear resistance
• Good abrasion resistance
• Good resistance to petroleum/synthetic based oils

Cons:

• moderate heat resistance
• poor weather resistance

Urethane:

Temperature Range: -22F - 230F

Pros:

• Excellent abrasion resistance
• Excellent strength and rigidity
• good weather resistance
• good resistance to petroleum/synthetic based oil

Cons:

• Low Compression
• Poor water resistance
• moderate heat resistance

Silicone:

Temperature Range: -78F - 392F

Pros:

• Excellent extreme temperature properties
• Excellent compression
• Good resilience
• Highly weather resistant

Cons:

• poor friction/abrasion resistance
• poor oil resistance

Viton:

Temperature Range: -4F - 392F

Pros:

• Excellent heat resistance
• Good compression
• Excellent resistance to virtually all oils/solvents

Cons:

• Poor low temperature flexability
• Poor resistance to hot water/steam

There's a lot to be said about the differences between buna-n's "good abrasion resistance" and urethane's "excellent abrasion resistance".

Also, note that the buna-n has "excellent compression". You have to evaluate whether or not compression is something you want your o-rings to do.

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How To: Paint a V-Force Grill Multicam | My E-Tac (work in progress)

I bought a pack of very small to big orings over a year ago and still have them. They are all black and like a rubber, what they are made of I don't know but they are my choice as they are paid for and I have a good amount of them.

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Another note to add with the BUNA orings. Traditionally, most paintball orings are BUNA 70. There are BUNA 90, which are a little harder (durable), but less forgiving with elasticity. I mention this because I use the BUNA 90 on my Havoc and they seem to last a long time. I have tried the Teflon and other orings and found that the BUNA 90 is great for those situations that require a durable oring, but still allow them to flex some as you install. Anyway..... that's my two cents and that is all I have to spend.

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A fart is nothing but the lonely cry of an imprisoned turd

I know my man has, buys, and use's thee Buna-90's.