HiPAC....what type of seals do you use?

[Canadianguy55]

I'm new to the HiPAC and was wondering what kind of seals people are using for 2000 psi and 3000 psi?I'm shooting 2000 right now!

Greg

[Nick_59]

The black seal that is packed with the hipac is recommended for 3000psi,   I've had no problems leaving the stock seal in place at lower pressures. 

[Gippeto]

IMO, the supplied seal leaves much to be desired. I use either a captive o-ring or a modified bonded washer/dowdy seal. There are some other local fellows using delrin seals to good effect as well.





Al

[Ribbonstone]

And in a kind of reveral, have had no problem using the black seal at lower pressures either.  Considering you have to have the whole thing apart to fix the valve in place, may as well use the HiPac issued black seal.

Can't speak for all the other guys, but when I set one up to seal, will work with just the buck-naked valved air tube.  Seat the conversion tube by had, fill to 2K, dunk it in a bathtub of soapy water.  If it leaks, crunch it a bit more by hand.  If it still leaks, the turn by wrench.  If it still leaks by 1/4 turn, then there is something broken and you need to start over.

Idea here is that the conversion tube will expand a tiny bit when pressurriced  to 2.4-3.0K. Not only radial expansion, but by length as well.  So unless the valve is FIRMLY fixed in place, it will leak...but it the valve is firmly fixed in place, it should seal by strong hand assembly.

As for the valve stem, would be nice to convert to a Discovery (Delrin) valve stem, but have had them run for well over a year on the issue soft-plastic co2 seal.  I just don't freak out when the issue valve stem blows (kind of expect to let go sooner rather than later).

[centexmarauder]

I have been using the supplied bkack seal and have had  no issues. I run 2700 and have had my gun apart numerous times with no resealing issues. My setup and shot string numbers are on the hipac forum if you are interested.
Oh and double what ribbonstone said the disco valve is the way to go
 Matthew blinn/centexmarauder

[Canadianguy55]

Well my stock tan seal blew on the inside hole probably from the stem,it was working quit well,I tightened to much when I replaced with the black seal...my bad!So now i sent my 2240 to someone...I'm thinking he will put the bondable washer in I sent with it.I would have tried the bonadable washer myself but I would have had to roll into the valve face and didn't want to mess the valve up.

I want to stock up on seals but not sure what to try if the bondable washer fails eventually.I was only given one of them.

I was thinking of one of those valves to,would you have to do any further work on the stem?

Okay I will get some of the black seals from the HiPAC store....thanks for the quick responses

I don't have a lot of machine shop type tools at my disposal

[centexmarauder]

Yup with the black seal i tighten the hipac by hand and fill. Has never leaked on me. Now on the other hand the fill nipple o-ring did fail on me. i repkacef it with a higher quality compression resistant rubber and have had no problems
 Other than having 49 o-rings i don't need.lol I really enjoy me hipac i get 10 shots at 29 fpe with a sd of between 2-5 depending on the luck of the draw from a unsorted tin of pellets

[Gerard]

Black seal leaked, so I tightened a bit harder and pumped to 2,2200psi, then the seal blew. Tried another and it blew more easily. Tried delrin and it sort of boiled or something, never seen anything like that with delrin, so I made one out of ertalyte. Works great after about six months so far, filling to 3,000psi without problems.

[Ribbonstone]

Nice job...will have to try that.

[Gerard]

Forgot to mention a couple of details. The brass collar on the stock valve is folded inwards making proper fitting of a hard plastic seal impossible. So I put the valve in my lathe and turned it down about halfway and cleaned up the inside edge slightly to get parallel edges. The seal itself was cut to fit tightly into this recess, snapped into place with moderate pressure. The opening could have been a lot smaller - 1/16" would be plenty, but I wasn't thinking properly about that when I made the seal. The stepped cut for the nose of the HiPAC is likewise a snug fit to that part.

[Ribbonstone]

Will have to wait until one of the back seals dies...which may be a wait as they don't seem prone to that now that the valves are firmly fixed in place. 

Don't care for the 22XX trigger once loaded with very heavy spring tension, so the highest I run the two still in serious service is 2400-2500psi.

May not have anything to do with it, but I do make sure the valve sits in the center of the tube (it has a bit of slack) so that the HiPAc tube mates with the seal kind of dead-flat.  Cock-eyed valve tends to let the mating surface be uneven, which seems to make sealing more difficult.

[Gerard]

Don't care for the 22XX trigger once loaded with very heavy spring tension, so the highest I run the two still in serious service is 2400-2500psi.

Hey, if it ain't broke, don't bother opening it up!

I've been posting this animated GIF here and there lately whenever I read of someone expressing less than serious like for their 22xx trigger. I'm a little bit in love with my trigger since I did this:



A guy named Glenn Davis on a network54 thread did a mod something like this, though he used JB Weld to glue a strip of steel on top of the trigger's rearward interface with the sear arm, soldered a little Allen-key-looking rod of steel into the end of the sear, and added another hooked rod to the rear bottom end of the trigger part with a spring connecting to the lower frame. That spring seems unnecessary with my changes.



I put the front pin (a small nail with the head filed narrower on two sides) in the crotch of the trigger instead of extending the part higher, increasing mechanical advantage for the extended sear arm. Drilled and soldered in a pin on the end of the sear instead of soldering it along the top edge. Couple of tricky holes to drill but it worked out nicely. The trigger is at times firing before I realise I've squeezed it that hard. Doesn't go off accidentally, just tends to trip in the middle of a short, smooth pull, the way a proper trigger should release. Effort is very light, about 250grams, which is a bit less than half the setting on my Pardini K12 (widely reknowned as one of the most consistent and best-feeling triggers in the world of ISSF air pistol competition) which is set at 525grams for matches. People trying the Pardini for the first time are often startled by how smooth and easy it feels. The 2240 trigger feels as good and is half as hard to pull. A mod I highly recommend.

Of course the stiffness of the harder hammer spring remains a problem for other reasons. Mostly I found it to be excessively hard on my custom hollow probe bolt. I'd found early on that the stock knob just bent when trying to pull that hard Powermax spring back, so I made a custom bolt and drilled and tapped it for a high quality 10-32 threaded bolt, then put that through a piece of canvas micarta turned down into a comfortable thing to pull, and resting snug against the steel breech such that it bore at least some of the stress of pulling back. Still, after some thousands of shots (and this with my harder hammer spring trimmed to just 29mm long and using an RVA to get the length back, also with a 40% lighter hammer and other mods) the threaded hole started to distort, catching in the breech's back end a bit. Made a new one when I went to regulated HiPAC use (slightly modified Robert Lane CO2/HPA conversion Lancet regulator, set at 800psi) and found a much lighter spring which delivered sufficient force for my power needs. Just slightly heavier than the stock spring proved more than sufficient with only 800psi to bash against, though I initially tested at a regulated 1,100psi and the lighter spring was fine at that pressure too.

[Ribbonstone]

Aren’t “match accurate” but I consider the above 3 HiPAc conversions (one QB and two 2260) as “PCPs”.  May be home brew, but if it walks like a duck…quacks like a duck…it’s a duck.