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Posted: Fri Oct 26, 2007 3:52 am
by ALIHISGREAT
i think the only way to get the valve out of the pic would be to make one, but i could be right in thinking that a schrader could be adapted

because when you depress the pin on a schrader the air escapes, but i'm not sure how effective this would be because i can't imagine a schrader used like that would have a high flow.
Posted: Fri Oct 26, 2007 5:04 am
by jackssmirkingrevenge
ALIHISGREAT wrote:i think the only way to get the valve out of the pic would be to make one, but i could be right in thinking that a schrader could be adapted

because when you depress the pin on a schrader the air escapes, but i'm not sure how effective this would be because i can't imagine a schrader used like that would have a high flow.
why use a schrader when you can use a blowgun?
I don't know where to get one like they have in the picture.
for our purposes, hammer valves aren't ideal. You best bet for a first valve is to get yourself down to a gardening supply shop and buy a sprinkler valve (for a pellet gun a 3/4" valve will do nicely) and add a couple of simple modifications to actuate pneumatically.
Posted: Fri Oct 26, 2007 5:09 am
by ALIHISGREAT
he has already made some sprinkler valve pellet guns... so maybe he wants to make something more advanced and different...
Posted: Fri Oct 26, 2007 5:23 am
by Chuck
I will keep searching until I find what I need. They had they idea 200 years ago. I would think we could come up with some simple valve that would allow the thing to be opened inline without having a sprinkler valve or QEV valve. The technology we have today. Thanks Chuck
Posted: Fri Oct 26, 2007 5:35 am
by jackssmirkingrevenge
The best solution I can offer it this:
Find a good metal cap gun and remove the revolving drum mechanism, keeping the trigger and the hammer. Then tage a blowgun and remove the lever which you press with your finger. Hook up the blowgun to a chamber and a barrel, then fit the cap gun mechanism in such a way that the hammer strikes the stem of the blowgun.
The attached diagram should give a rough idea of what is needed:
Posted: Fri Oct 26, 2007 6:01 am
by Hawkeye
I really doubt a cap gun mechanism has the force required to knock open a blowgun with a fair amount of pressure behind the valve.
I'm really not sure where Chuck isn't understanding that a hammer valve is not overly complex to make. Most of the versions today are simplified versions of the old system which had to be more complex to work with lower pressure. Plenty of material out there to copy.
Posted: Fri Oct 26, 2007 6:05 am
by jackssmirkingrevenge
I really doubt a cap gun mechanism has the force required to knock open a blowgun with a fair amount of pressure behind the valve.
You can always beef up the spring or hammer weight.
Posted: Fri Oct 26, 2007 6:22 am
by ALIHISGREAT
i would like to see someone use a cap gun/blowgun for a valve and trigger it would be interesting to see, and it might allow you to get multiple shots off a chamber because the blowgun would reseal.
Posted: Fri Oct 26, 2007 10:08 am
by grumpy
Chuck wrote:I will keep searching until I find what I need. They had they idea 200 years ago. I would think we could come up with some simple valve that would allow the thing to be opened inline without having a sprinkler valve or QEV valve. The technology we have today. Thanks Chuck
how about something like this,
Posted: Fri Oct 26, 2007 7:04 pm
by Chuck
I wonder if a paint ball set up is going to be strong enough to push a 50 caliber ball out to the speed of the Lewis and Clark Rifle. I have a couple of old paint ball guns I could take parts off of. I appreciate you guys thanks for all the trouble. Chuck
Posted: Fri Oct 26, 2007 8:21 pm
by Hawkeye
Of course it won't. Paintball is usually under 300 fps. The Lewis and Clark gun was likely about 700 fps. You can easily make a single shot piston gun that shoots that fast but repeating capability is what you are looking for.
Posted: Fri Oct 26, 2007 9:14 pm
by Chuck
I know the paint ball gun shoots less FPS slower than what I was looking for, but I just thought of using the valve inside to make the thing shoot.Another thing I was thinking about with acess to multiple shots how would the balls stay inside the barrel with out rolling out. I know you could put a wadding in but that would take away from the multishot idea. I was thinking that the barrel was a slitley tighter fit then the receiver port for the ball. That would work. This rifle is starting to get interesting. Thanks Chuck
Posted: Fri Oct 26, 2007 9:47 pm
by DYI
Take a look at Clide's Slider gun, it has a great semi auto concept, and, best of all it can be built with simple materials and equipment (as long as you have a lathe and some rod stock).
Having access to a lathe at school, I'm now working on building PB cannons for a few people, usually to specs that wouldn't be quite field legal (i.e. nerf football at 700fps

). I can give you some good ideas, just PM me.
Posted: Fri Oct 26, 2007 9:50 pm
by Hawkeye
For a smoothbore there is a detent that holds the ball in place.
Posted: Fri Oct 26, 2007 11:38 pm
by jackssmirkingrevenge
Chuck wrote:I wonder if a paint ball set up is going to be strong enough to push a 50 caliber ball out to the speed of the Lewis and Clark Rifle. I have a couple of old paint ball guns I could take parts off of. I appreciate you guys thanks for all the trouble. Chuck
You'd need some pretty heavy modifications before that was possible, like long barrel, stronger hammer spring and heavier bolt, bored out valve to allow more flow etc.
edit: a better idea would be to shut off the valve that makes it an autoloader and have the bolt pulled back manually, that way you're not wasting gas loading it and at the same time you can have a much heavier spring.
The
Quackenbush XL ises a similar bolt-and-hammer-valve setup and CO2 and does 650 feet per second in 0.22 cal.