playin with a ball valve and fittings

[boar]

ok I picked up a 3/8 ball valve and some pipe fittings this weekend the valve was smaller than i wanted but was the biggest tsc had and sat after 5 its tsc or drive so i put it all together with a 6"x 1/2" resivor  and tried diff pipe and tubeing for barrels wound up with about 3' of 1/2" cpvc be cause it best fit some 240 gr .44 swc's i had layin around I found that at about 175 psi i could make a nice pop and a good dent in 3/4 plywood then the first compressor stoped makin pressure a trip to wal mart fixed that now i could get to 300 psi at 270psi i could put a hole through both sides of a 5 gal metal bucket
i also snagged a 1/2"x24" pipe for a air chamber to see if that made a difference next day i dusted off the croney and scrounged up a battery wow it still worked at 270 psi i was shootin 200-207 psi switched to the longer air chamber thats when the second compressor blew its hose off the new one I coulda fixed it but i figured since it was only a few hours old and it said 300 psi and i hadnt exceded that i should exchange it so back to walmart no problems exchangin it was dark when i got home croney doesnt like florescent lights so no readings back to shootin the bucket and playin with barrels ammo and such next morning armed with the new compressor i took a couple of shots with the small chamber still about the same 205 206 put the large chamber back on could only get it up to 170psi then 120 then not even 100 checked for leaks on the chamber put the small chamber back on still nothing so took that back got money back and grabbed a foot pump the gauge only went to 100psi but i figured im a kinda heavy guy and was despert well at 100psi and a pump it blew the seals so a started tearin down some old compressors i had layin around got 1 workin real good after cleanin it all up re wirin it and tightening everything up it started blowin hoses replaced those ok i was in air again got a couple of bucket shots a 300psi put the big chamber back on and striped the gear on the compressor so i found 1 with a bad motor frankenstien time swaped motors started gettin air again (the kids were loving the frankin fixin goin on) for a while striped that gear too poped the gear off and modified a nut driver bit to fit the shaft and hooked it to the cordless drill it didnt turn fast enough couldnt git much air out of it sooo i never got to see if the larger chamber made a diff tomight i turned the valve around roughly mounted the whole thing to a plywood stock and put a spring and trigger on it now when i get some air again i can see how much diff that makes i think im gonna order one of those shock pumps looks like it would be handy and i need to be able to recharge in the feild with no electricity

Boar

ps i typed this with only 1 . 1 pair () and many misspeld words

[Pellethuntr]

Wow that was comprehensive... Sounds like you had some difficulties with those crazy little compresers. That shock pump setup looks like a good idea to me too. Right now I am using co2 and getting lots of power but not enough shots per fill you can check some of my earlier post to see some of the things I'm working on right now...

[theairgunman]

Sounds like you are really getting into it! The portable compressors that stores have been selling lately have been pure crap. When I started building my own airguns several years back, Walmart sold a little blue campbell hausfeld compressor that worked for a few years for me. Now the compressors dont even go to their max pressure or last more than a week.  I can wholeheartedly recommend a shock pump. I've had mine a couple of months now and have been using it up to the 400 psi max on a very regular basis. Not a problem at all with it. I will warn you, it takes a lot of work to pump up even a 8.5" by .5" chamber to full pressure (77 pumps per shot!).

[boar]

Im trying to git into it its no fun right now have things i want to try and no air till this weekend if i cant find anything better ill get another one from walmart take it back sunday evening they told me if they keep breaking keep bringing them back hmm kinda like renting one anyone got any idea what a ac compressor will do I remember when i was a kid people used those to air up tires

Boar

[theairgunman]

A AC or refrigerator will go up to 300 psi without too much trouble. They're a bit quieter too. Hang in there, once you get the air nailed down, the rest isnt too bad. Check into that shock pump as well, here is where I bought mine from: http://www.pricepoint.com/detail/16246-318_SET357-22-Sette_Products-855-Pumps/Sette-Air-2-ST-35-Universal-Shock-Pump.htm Looks like they are on sale too!

[boar]

thanx I looked at that pump on that site looks like a good price im gonna check some bike shops in waco this weekend just cuz im impacient might try the ac compressor tommarrow

Boar

[Pellethuntr]

 Just get one of those little hpa bottles that jerks sporting goods has for like $100. That will save you all kinds of hasles. And It can be reged down to whatever psi you want...

[boar]

tomorrow is friday besides being payday its also the only day I might get off work early enough to hit a decent hardware store and maybe a bike shop
I started a pump tonight hopefully get a few parts tomorrow and finish it see if it works if it does i can start tinkerin but the main focus for this weekend is AIR!!
this has been a hard week at work hard to stay on task

Boar

[boar]

ok last night i installed a larger air chamber and shot it at 160 psi thats about all the harbor freight compressor will do anymore it seemed more powerful even with the lower pressure but the chroney wouldnt work in the barn lastnight under the lights today after work there was some daylight left so i got a couple shots over the chroney 235 fps thats not a huge improvement but its just a little over half the pressure
picked up some more fittings and another of those walmart compressors so i can see what it will do at 280-300 psi also gonna tre some diff resivor sizes and configurations

boar

[theairgunman]

It really is amazing how much power you can get out of 150 to 160 psi if you use a large enough air chamber and long barrel (28 to 36"). This airgun:

will shoot a 278 grain .58 cal roundball at a little over 400 fps. It has a huge air chamber that doubles as the stock. I'm not sure if you've heard of GGDT, but it is a great program that can help you get an idea of the speed an airgun will shoot with various chambers/barrels/valves without having to actually build them. You can download it here: http://www.thehalls-in-bfe.com/GGDT/. If you put in accurate values, it seems to give reasonable results, usually within 5 to 10% of actual velocities.

[boar]

yea i looked at ggdt i plan to put it on the laptop b4 the trip so i can play with it on the way to mo next weekend
also I shot everything the same but took it up to 280 psi several times still shot 235-237fps then i tooa few more at 160 -180 psi except for 1 shot they were still in the same range kinda bafflin im thinkin it might be the small valve limiting it  any ideas? that i shot that was diff was at 160psi and 274fps no idea why that ons was so diff
i did grab a 3/4 ball valve yesterday we will see what it does later

Boar

[theairgunman]

It's definitely the small valve choking the flow if increasing the pressure doesnt improve velocity. It is always better to have the barrel choking the flow, not the valve. You'll also want to  make sure that valve is opening fast enough. If you can see the lever move, its going too slow. Put that 3/4" valve on, make it open fast using a stronger spring if necessary,  and you should see a pretty drastic improvement.

[boar]

Ok thanks I kinda figured it was the valve either lock time or size or both this evening i stretched the spring some more and took a couple of shots with no change on the chroney so that makes me think its more the valve size i mounted the 3/4 valve but have to rework the trigger b4 i can try it if i had a 3rd hand holding the valve closed then letgo when ready shoot

Boar

[boar]

ok i got it set up with the 3/4 valve i figured out a trigger system that will be flexable enough for reconfiguring this thing I used my caliper release from my old compound bow easy to move around and change stuff any way the new rig only shot 206 fps at 160 psi  and it doesnt go pop any more took it up to 260 psi and got 293 fps thats an improvement i then put a bit more stretch in the spring and shot it a few times at 160psi it seemed to help but was not enough light for the chroney i need to get a shorter stronger spring im not getting a pop sound anymore all i realy hear is spring and impact i think that means i either need a larger resivour or more pressure at either rate with this valve i feel i can go quite a bit farther the caliper release works well as a test trigger kinda awkward to cock but holds well and releases well and is easy to rearange for different setups might be able to incorpirate it into a feild gun  i think when its all said and done when i get ready to build something to realy use ill wind up building a piston type valve like in that little pistol you built something similar to what i think your building now but well see

Boar

[theairgunman]

How's your airgun projects been coming along?