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All Springer/NP/PCP Air Gun Discussion General => "Bob and Lloyds Workshop" => Topic started by: lloyd-ss on December 17, 2011, 11:02:55 AM

Title: Building a PCP pistol
Post by: lloyd-ss on December 17, 2011, 11:02:55 AM
I am in OCD mode right now working on a PCP pistol.  
The valve is working, but I have a long, long way to go.  The barrel in the picture is about 8" long.  All I have shot so far is air, but... oh yeah!   ;)
Lloyd

edit- P.S.  Yes, blocky, ugly, temperamental, no trigger, no magazine, but headed in the right direction.

(http://i226.photobucket.com/albums/dd79/loyd500/PCP-pistol/PCP-pistol-1a.jpg)
Title: Re: Building a PCP pistol
Post by: 0351_Vet on December 17, 2011, 11:24:49 AM
It's a beauty Lloyd. :)
Title: Re: Building a PCP pistol
Post by: lloyd-ss on December 17, 2011, 11:33:53 AM
It's a beauty Lloyd. :)
I guess beauty is in the eye of the beholder.  I went back and edited in a disclaimer to my post.   ;)
Lloyd
Title: Re: Building a PCP pistol
Post by: gene_sc on December 17, 2011, 11:38:07 AM
Good start Lloyd, for sure ya gots to take it a step at a time. I hate re work but in my case it is always staring at me...:)

Will be watching your progression.
Title: Re: Building a PCP pistol
Post by: 0351_Vet on December 17, 2011, 11:53:49 AM
What Caliber Lloyd?
Title: Re: Building a PCP pistol
Post by: lloyd-ss on December 17, 2011, 01:40:23 PM
What Caliber Lloyd?
Right now I have a .308 barrel on it more or less as a place holder.  I have to determine how much air the valve will flow efficiently and how I want to deal with air tank(s).  Right now it only has 44 cc's inside the hollow pistol grip.  I need at least 4 times that.
Title: Re: Building a PCP pistol
Post by: rsterne on December 17, 2011, 01:44:19 PM
Interesting project.... but I won't lie and tell you it's beautiful.... although the machining certainly is.... I assume the reservoir in in the grip?.... or is it just tethered?....

Pistols over 500 fps are Restricted Weapons in Canada.... can only be shot at a range.... and you need a permit to get it there.... Not a lot of point, unfortunately....

Bob
Title: Re: Building a PCP pistol
Post by: 0351_Vet on December 17, 2011, 02:47:26 PM
.308...... :) One of my favorite calibers.
You continue to amaze me Lloyd.
"Go Big-Bore, or Go Home" :)
Title: Re: Building a PCP pistol
Post by: dk1677 on December 17, 2011, 09:45:10 PM
That should be very cool Lloyd!
Title: Re: Building a PCP pistol
Post by: gamo2hammerli on December 17, 2011, 11:01:18 PM
Wow....nice work.  Maybe I'm just easy ha ha.  Can't wait for the finished product.
Title: Re: Building a PCP pistol
Post by: lloyd-ss on December 19, 2011, 12:49:06 AM
Thanks for the comments everybody.
One step closer.  Still ugly, but proof of concept is ok.

http://www.youtube.com/watch?v=tO7kwPkINb0# (http://www.youtube.com/watch?v=tO7kwPkINb0#)
Title: Re: Building a PCP pistol
Post by: MustangMike on December 19, 2011, 06:41:51 AM
Holy cow batman, I am constantly amazed by wealth of information on this site. But never have I seen so many people in place with talent like this, I think some of these airgun companies need to hire a handful of our members here for r&d and then not change anything after the airgun is researched, designed and built

Lloyd I don't even know where to even start with a compliment on what you've built. So I hope that in its self is a compliment
Title: Re: Building a PCP pistol
Post by: Nomadic Pirate on December 19, 2011, 12:35:41 PM
I'm in the market for a good .357 pistol if you ever make one :)
Title: Re: Building a PCP pistol
Post by: MustangMike on December 19, 2011, 01:54:00 PM
just watched the video, couldnt watch it from my phone..

is it just me or does that pea shooter have a little kick to it ?
Title: Re: Building a PCP pistol
Post by: lloyd-ss on December 19, 2011, 02:07:31 PM
just watched the video, couldnt watch it from my phone..

is it just me or does that pea shooter have a little kick to it ?
Mike, yeah.  That's after I turned the wick down on it.  Dual air tubes will be needed.
Title: Re: Building a PCP pistol
Post by: lloyd-ss on December 19, 2011, 02:09:18 PM
I'm in the market for a good .357 pistol if you ever make one :)
If I can get the .308 functioning well, then I think I'd be obligated to try .357.
Title: Re: Building a PCP pistol
Post by: Bandit_46 on December 19, 2011, 09:46:43 PM
Absolutely Wicked!!! Nice Concept as well Lloyd!
Title: Re: Building a PCP pistol
Post by: lloyd-ss on December 20, 2011, 08:29:13 AM
The beginnings of the clip.

(http://i226.photobucket.com/albums/dd79/loyd500/PCP-pistol/Magazine-1a.jpg)
Title: Re: Building a PCP pistol
Post by: 0351_Vet on December 20, 2011, 09:11:15 AM
Way cool Lloyd......please keep us posted.
Title: Re: Building a PCP pistol
Post by: hoagy on December 21, 2011, 01:03:22 PM
ugly is as ugly does... keep at it!
Title: Re: Building a PCP pistol
Post by: lloyd-ss on January 04, 2012, 08:59:01 AM
I have  temporarily slowed on this while working on the Disco double tube project.
Velocity so far is around 600 fps with 77gn .312 bullets and 10" barrel.  The valve in this proto is very compact and I need to put a slightly longer barrel on it and see what happens, but I will try and get more velocity out of it with the 10" barrel, too.  That would be my preference.

She's in the rough.  My favorite part is the target grade trigger, LOL.  ;D 

(http://i226.photobucket.com/albums/dd79/loyd500/PCP-pistol/pcp-pist-3b.jpg)
Title: Re: Building a PCP pistol
Post by: oldpink on January 04, 2012, 09:20:21 AM
Funny thing, Lloyd, unlike nearly all of us here, you will probably be able to get this working and working very well from scratch.
;)
Title: Re: Building a PCP pistol
Post by: BenjiHunter on January 10, 2012, 08:40:37 PM
Wow,that gun packs some serious punch !
Title: Re: Building a PCP pistol
Post by: 1377x on October 01, 2012, 04:33:28 AM
i missed a bunch of cool threads while i was in the hospital for 3 months.this is really interesting
Lloyd have you worked on this project lately?
Title: Re: Building a PCP pistol
Post by: lloyd-ss on October 01, 2012, 11:15:10 PM
i missed a bunch of cool threads while i was in the hospital for 3 months.this is really interesting
Lloyd have you worked on this project lately?
Right now it is sitting in a clear plastic box (among several other clear plastic boxes) over one of my work benches.  It is looking at me wondering when I am coming back to work on it again. It is on the list..... and I think about it a lot.....  ::) ..refining...redesigning..... if that counts??
Lloyd-ss
Title: Re: Building a PCP pistol
Post by: 1377x on October 02, 2012, 01:24:09 AM
that counts!
it would have been bad to see this kind of post,
hmmm, now where is that pcp pistol project? oh yeah i scrapped it. ;)
Title: Re: Building a PCP pistol
Post by: venxxxxx on February 26, 2013, 06:11:08 PM
any updates ?
How about convert a nail gun into a pcp pistol ?
Title: Re: Building a PCP pistol
Post by: french falcon on April 06, 2013, 08:57:48 AM
I'd LOVE to see it work Lloyd!
Best of all would be (I think) something along the lines of your e-valving system applied to a pistol..
Something compact, 6 to 8" barrelled which would leave space for a LDC,
caliber .32 or 9mm, for 0->25 yds shots. Would be an astounding hunting pistol.
Title: Re: Building a PCP pistol
Post by: lloyd-ss on April 07, 2013, 12:03:00 PM
This is still in the box on the shelf waiting to be worked on again.  The valve is not conventional and takes up very little length in the gun. I'd like to get it working reliably but there are still a few engineering challenges in it.
Title: Re: Building a PCP pistol
Post by: french falcon on April 19, 2013, 03:08:36 PM
Hi Lloyd!

 I bet it's along the lines of a monostable pneumatic operated valve, instead of the conventional poppet valve, which is an oscillating sytem by nature?
 I believe it's one of your greatest ideas in the development of your e-valve, to design along the principles of the industrial pneumatic operated valve, and prove it's fast enough for airguns. No more oscillating reactions from the valve, and an almost instantaneous pressure rise to the maximum value, which in turn maximizes efficiency - and minimizes pressure at the muzzle...

 Correct me if I'm wrong, but something CAN be designed with a return spring to close the valve, once it has been opened by the hammer strike?
Title: Re: Building a PCP pistol
Post by: lloyd-ss on April 20, 2013, 12:02:13 PM
Hi Lloyd!

 I bet it's along the lines of a monostable pneumatic operated valve, instead of the conventional poppet valve, which is an oscillating sytem by nature?
 I believe it's one of your greatest ideas in the development of your e-valve, to design along the principles of the industrial pneumatic operated valve, and prove it's fast enough for airguns. No more oscillating reactions from the valve, and an almost instantaneous pressure rise to the maximum value, which in turn maximizes efficiency - and minimizes pressure at the muzzle...

 Correct me if I'm wrong, but something CAN be designed with a return spring to close the valve, once it has been opened by the hammer strike?


With the e-valve, small solenoids used in very high speed industrial applications, with quick response time and almost perfect repeatability are the key.  I have found the Mac valves (no relation to Mac1 airguns) www.macvalves.com (http://www.macvalves.com) to perform well.  I am sure their are other equally as good brands, maybe even better. Considering that the dwell time needed to maintain consistent velocity across a 2000 psi range may run from (hypothetical)  2 milli sec to 5 milli sec with a required resolution of 20 micro sec, the fact that it functions at all is pretty amazing (to me anyway).  In actual application the mechanical lags are significant and the dynamics of the main HPA valve must be put into a push-pull situation with lead and lag varying across the pressure range, effectively preloading the main valve for fast opening and closing, while maintaining a fail-safe system such that any malfunction will close the main valve as the default mode.  It is easy to open the valve.  Closing it in a timely manner is the trick... and it is not easy.

Return springs, I think, can work in a balanced valve, but  I have never been able to master it.  If the valve is the least bit unbalanced and the HPA gets the upper hand, the return spring is at a major disadvantage.  The conventional knock-open valve, with the HPA functioning as the return spring is a pretty good design and I haven't seen much that is "really" different in a mechanical design.
Lloyd