2400kt, Bottled, Regulated

[rsterne]

The regulator cannot top up the plenum during the shot, it does so between shots.... so flow through the Disco fill fitting is not an issue.... You can remove the check valve for your purposes if you wish....

Bob

[aPpYe]

I guess I can go with the co2 ones then...  A lot of these are sold with coiled hoses, so I guess I can just discard that part...

As far as the regulator topping up the plenum, that part I was aware of.  I was figuring that I might add another cc or two by allowing the plenum to extend through the hose and into the ASA.  I am guessing that at some point, the narrowness of this "extension" would have less of an effect on average pressure, say if I had gallons of 1400psi air separated from the tube by a very narrow open port, that extra air isn't gonna be much help during the shot right?   This has me thinking, might a regulator be more "accurate," meaning tighter psi range between shots if there was an extremely narrow port between the regulator and the plenum of air it feeds?  The idea is that it would top it up in a slower, more controlled fashion. 

Anyway, I don't really even know how regulators work in the first place, just tossing around some newbie theory!  I just know that they are these magic things that use shims or springs ("wing of bat" or "eye of newt") of some sort that adjust the magic. 

What kind of psi range do regulators typically achieve shot to shot anyway?  Bob mentioned that the delrin o-rings that mac1 puts into the ninja regs he sells create a tighter psi range ... how much tighter?  BTW, I finally called him, but only got voicemail.  I am gonna get a 6" braided steel hose and a ninja reg from him.  I would like to get the whole regged tank (13ci) package from him, but I don't know if that is gonna happen until I talk to him.  If he doesn't have the tank, I can always get the bare tank from rap4...

Also, does anyone have any opinions on the street elbows I mentioned a few posts ago?

[rsterne]

Ninja regulators hold a shot-to-shot pressure variation that you can't see a difference on a gauge that has 50 psi increments, so that would be less than 10 psi.... From a full tank down to 1000 psi, however, they might drop up to 50 psi.... If your gun is tuned to the "knee", which means near the peak of the velocity curve, that 50 psi won't cause any measureable change in velocity, however.... Just the variation in pellet weight and fit in the barrel has a greater effect on velocity than regulator output variation in a properly tuned gun.... IMO, have a tiny hole between the regulator and plenum is probably the wrong way to go, regulators work better if the pressure can come up to the setpoint rather quickly.... although to be truthful I have never seen that to make any difference with a Ninja reg. but it has been reported with some brands of "in-tube" regs....

Bob

[aPpYe]

heh heh ... that's what I get for theorizing on something I had no idea about!  It makes sense that pellet variation would likely have a pronounced effect.  I often find myself checking pellets before every shot, especially for skirts that are out of round.     I think I am gonna take some time to learn about these regulators...

[aPpYe]

Okay, I get the basics of how they.  Simple enough.  In Wikipedia's example, Inlet pressure, combined with outlet pressure on a diaphragm overcomes spring tension, keeping a valve closed.  When outlet pressure drops, spring overcomes the combined pressure on the diaphram and opens the valve, allowing more pressure to enter the outlet side, which pushes on the diaphragm, closing the spring again.  I think i got this right.

So in the case of the ninja reg, I am guessing the concept is the same, but using a stack of shims to provide spring pressure ...  I did find this drawing, but I am not sure what I am looking at honestly, or how similar it is to a ninja reg.  The valve looks to be in its closed position, and I recognize the shims, but I don't know what the pink thing in the middle, or the blue circle at the top.

[aPpYe]

Also, I am trying to decide how long I want my braided steel cable.  Based on my mockup drawing, I figure 6" would be about right, but does anyone know how accurate my measurements are here?  All I had to go on was the CCS graphics where you choose barrel sizes.  In a photo editor, layered the various barrel length guns pixel-perfect on top of each other, did a little arithmetic based on what pixels the 18" and 24" barrels ended at and came up with the ruler in my pic.  The 10.1" and 14.6" barrels seemed to fall in line just about perfectly, so I figured all was correct.  Each red line is supposed to be exactly one inch apart in the drawing...

Here is the latest version of my mockup:

[BigTinBoat]

So in the case of the ninja reg, I am guessing the concept is the same, but using a stack of shims to provide spring pressure ...  I did find this drawing, but I am not sure what I am looking at honestly, or how similar it is to a ninja reg.  The valve looks to be in its closed position, and I recognize the shims, but I don't know what the pink thing in the middle, or the blue circle at the top.

This is just like the Ninja SHP reg. The pink thing keep the air in the bottle when reg pressure is reached, the blue thing keeps the air in the reg when nothing is attached to it.

[aPpYe]

Aaaaah now it all makes sense!  So the air goes into those ports next to the "pink thing" and causes the piston to go down and compress the bellvilles...

Anyway ALL PARTS HAVE BEEN ORDERED!!!  I am going to be down in the Los Angeles area for the thanksgiving weekend so I will be stopping by Mac1 personally to pick up my regulated tank, braided line and benjamin pump!

Hopefully the gun arrives soon so I can start drilling holes and violating it!

[HappyHunter]

Also, I am trying to decide how long I want my braided steel cable.  Based on my mockup drawing, I figure 6" would be about right, but does anyone know how accurate my measurements are here?  All I had to go on was the CCS graphics where you choose barrel sizes.  In a photo editor, layered the various barrel length guns pixel-perfect on top of each other, did a little arithmetic based on what pixels the 18" and 24" barrels ended at and came up with the ruler in my pic.  The 10.1" and 14.6" barrels seemed to fall in line just about perfectly, so I figured all was correct.  Each red line is supposed to be exactly one inch apart in the drawing...

Here is the latest version of my mockup:

Hi Patrick,
Don’t know if this helps or not, but I had an extra 13CI bottle laying around doing nothing along with a remote coil hose (just needed the ASA on/off valve, but didn’t feel like taking it apart for the pic) and my old 2250, so did a quick mock-up to give you a reference for your measurements.

Bottom of bottle is flush with forestock mounting tab, barrel is 14”. If you used a “street” elbow in ASA on/off valve, you’d be looking at around 4.5” - 4.75” for your braided line with that configuration.

[aPpYe]

Hey man, thanks for taking the time to do that!  I was able to lay your pic right on top of mine almost seamlessly and the rulers matched up, so it looks like Crosman's graphic is pretty much spot on.

...What is the green thing between the regulator and the ASA?

The idea I have been rolling with for the last day or so has been to do away with the fill nipple and send the hose fitting directly into the fill housing.  With this configuration I was thinking I would go with 5-6" to the elbow...  I initially thought of going this route to eliminate a potential source of leaking... Anyone have experience with having quick disconnect fittings connected long term?

The other thought was that this extends the plenum by a few nosehairs by eliminating the check valve and having open air down into the asa.  Anyone have any ideas on how many nosehairs I am gaining here?  A little more power is always fun...

[aPpYe]

So I ordered this ASA off of ebay earlier today.  It seemed as good as any ...

[BigTinBoat]

So I ordered this ASA off of ebay earlier today.  It seemed as good as any ...

yep, that was the american made one with the degrasser built in, right?

[HappyHunter]

...What is the green thing between the regulator and the ASA?

That would be the bonnet that houses all the reg internals - pin valve, piston, springs, shims etc, etc...that's the part you need to remove in order to service the reg or adjust output pressure.

[aPpYe]

Oooh I see.  I wasn't paying attention, the bonnet is just a different color on that reg...  I was thinking it was some other attachment between the regulator and the asa.

[aPpYe]

Bob, there is something wrong with your website...  I see no mention of the word "airgun," "reguator," "barrel," "caliber," or even "pellet!"  Although I see a nice looking crosman in one of your hunting pictures...  Even without an "airsonal" museum, your inn looks like a really nice place to stay!

Anyway have a happy Thanksgiving everyone!  Or I guess as Canadians might say, "Enjoy your Thursday, Thanksgiving was six weeks ago!"

[rsterne]

*LOL*.... my wife loved the "six weeks ago" comment.... I think if we up here in the Frozen North waited until late November, the Turkeys would have all been eaten by Coyotes!....

Bob

[aPpYe]

Up here we get an occasional dusting, according to people in town anyway.  As a matter of fact, we just got snow yesterday for the first time since we bought the house last year!  I hope we don't get snow that sticks for long periods...  I grew up in Los Angeles, my daughter never even saw snow before.  Speaking of which, it's time for that four hour drive now...

[aPpYe]

So I now have my bottle, pump, some 90 durometer orings to replace what I will get with the disco valve and fill adapter, and an extended probe to replace the stubby thing that comes with the 2400kt.  At least I think the 2400kt comes with the same one that goes in my 1377.  Tim at Mac1 mentioned to me that this gets you better accuracy because the pellet is already square in the rifling when the air starts pushing it forward, rather than still sitting somewhat in the leade and being slammed into the rifling at whatever angle it wants.  At least that is how I understood it...

I saw one person on youtube who made an extended probe using a piece of bailing wire and some drilling ... I might try that on my 1377.

Tim did not want to set my reg to 1400psi with a 1.8k burst disk, so he went with 1250.  It currently has a 5k disk on both sides because he did not want to burst disks while he was adjusting pressures.  I almost walked out of there with it like that!  He gave me a 1.8k and a 3k, along with some shims to play around with things if I want.  Once I get my ASA (so I can use something a little more "proper" to depress the ball and degas), I will be installing the 1.8k disk on the output side.  I think I will see what I can get out of the 1250psi setting before I start messing with shims ... or maybe I won't!   I am gonna have to learn about shims and bellvilles now ...  I figure someone here must speak ()()()()(||||?

I also gotta say, Tim at Mac1 is a pretty cool guy!  Fiesty as *(&^, but he really went the extra mile to make sure I was set up well, explaining things as he went along.  I was in his shop for a good hour and a half and he spent a lot of time explaining things to me.  Not only that, but I my newly steroided silver streak back from him about a month ago that I was having accuracy problems with, and he cut a nip off of the end of the barrel and recrowned it for me free of charge!  Of course, I did spend almost $400 in his shop that day ... Today is test day for that thing.  I am driving back up north tomorrow, so it has to be today, or else I will have to wait for Christmas to get it back to him again if it still shoots shotgun patterns at 20 yards.  I hope my parent's are gonna be cool with me popping off a few groups in their suburban (well, they still have an acre) yard!  Streaks are not known for their diminutive voices...

[aPpYe]

Hi All,

Before I start building this thing, I figured I would find out from all of you what your experience is with the desiccant filters I see online.  I picked up a Benjamin pump.

Here is an example:
 

I see this home made one here as well...  It seems like it would work... I guess I will be spending the drive home reading about the different silica gels...


Is this all snake oil, or do they actually work?  I know I don't want my gun to rot out from the inside. 

... How often should I expect to be tearing things down as a maintenance cycle?

[aPpYe]

Okay!  I put my pump together, pumped the bottle to 3000psi and figured they were in good working order.  Tim built my reg with 1250psi output and a 5k disk on both sides.  He also gave me two really thin shims and one thicker one.  After emptying the bottle, I threw all of them at it and pumped it up.  After reaching over 1600psi (and climbing) on the reg tester I put together, I emptied everything and took the thick shim out.  This got me right where I want to be.  I saw that the reg tester hovered right at 1400psi when the bottle and pump gauges read 1700psi.  I continued all the way up to 3000psi and saw that the reg read 1450psi.  As I understand things, this amount of "creep" is normal.  I again emptied the bottle and installed the 1.8k disk on the output side, replacing the 5k Tim had on there initially.  I pumped all the way up to 3000 psi and the disk is holding 1450psi.

...At least it didn't burst.  I do hear some air coming out of there now...  I hope I did not install it too tight or something.  I hand tightened it and gave it maybe a quarter to half a turn more, I don't remember.  I wrapped white teflon tape around the threads two times...  The sound does seem to be coming from the two holes on the side of the disk housing though.  Do burst disks ever just leak slowly like that?  Don't they normally either stay solid or burst suddenly?  Maybe it is defective?  Tim did not test it while I was there...

I will take it apart tomorrow and try again.  I pumped that thing up four times over the course of about an hour and I am tired!