Little PCP project...new pics

[Gippeto]

Been working on this for a little while now. Finally able to do a few test fires on co2 (N2 and scba bottles are empty. ).

No chrony numbers, but penetration in pine is about 3/4" with 14.3gr cp hp. Should be...better...on air.

Designed around a minimum yield at 9000psi, and hydro tested at 6000psi, for an operating pressure of 3000psi max.

It's my first attempt at multi shot pcp, and I'm feeling pretty pleased thus far. Have to remove some weight from the hammer, and see if that helps with the hammer bounce. Have already put in the heaviest valve spring I can find. Still vicious hammer bounce.

Once I get the hammer bounce under control, I think that'll be the time to dig out the chrony and work on getting a bell curve.

I think I might keep the tube stock and add a wood fore end and grips.

Crosman based, and .22cal.

Anywho...enough yammering...here's a pic.





More pics as requested. Managed to bugger the valve seat taking it apart too. Still in the tube, are the fill plug, the adjustable spring seat and valve spring. The spring seat is pretty much the same as the rear RVA with a hollow bolt to allow gas transfer.

[Crna Legija]

once again amazing work Gippeto, that beast looks sick cant wait for damage pics and close ups of the gun, how many shots you getting each fill?

[Patto]

yeah man beautiful build !! and so slim

So is there any chance of some broken down photo's please ??

[michaelgohjs]

beautiful build man

how do you get it to the thousands for psi?
is it cos of a small chamber? and what pump are you using to get that thousands of psi

[inonickname]

beautiful build man

how do you get it to the thousands for psi?
is it cos of a small chamber? and what pump are you using to get that thousands of psi

Second sentence.

Finally able to do a few test fires on co2 (N2 and scba bottles are empty. Sad ).

Was it once a 2250 by any chance? Obviously, nice work and we'd all like to see more

[Gippeto]

Thanks guys.

Shots per fill will be determined by how well I get the hammer bounce under control, the fill pressure I tune for, and ultimately by the power level I set.

Planned power level is ~900fps with JSB exact jumbos (~16gr IIRC).

The only Crosman parts are the barrel (23.5" cut and crowned), barrel band (2240) and the grip frame/trigger assembly(2240). I made the tube, internals, and the breech/reciever assembly.

I didn't take pics of the internals, but I will the next time I have it apart.

@ Patto...this uses the valve we talked about.

[Gaderelguitarist]

Planned power level is ~900fps

Are you sure it won't be over 9000?

This looks very believably factory built. I think that putting some wood on this might make it look better.

Gippeto do you ever feel a bit hesitant to pick up one of your guns loaded at such a high pressure? I feel as though I'd never get past touching it and running away.

[Gippeto]

Planned power level is ~900fps

Are you sure it won't be over 9000?

This looks very believably factory built. I think that putting some wood on this might make it look better.

Gippeto do you ever feel a bit hesitant to pick up one of your guns loaded at such a high pressure? I feel as though I'd never get past touching it and running away.

9000? That'd be something wouldn't it.

I'll take that as a complement.

Do the calculations + double check them + hydro test = trust

I use yield strength for calculations in place of Tensile strength. If there is a failure, it should be a yield failure, and it should be at three times my max fill pressure, which will be ... difficult...with my fill source being only 4500psi. (1.5x max fill at the most)

[Gaderelguitarist]

It was meant as a compliment . My thoughts on the wooden parts are only so because I think that metal would be more in keeping with the aesthetic of this gun. Still, nothing beats good ol' fashioned wood grain.

And I respect your approach to safety.


Also the 9000 thing was an internet joke

[Gun Freak]

Here you go Gippeto,
[youtube][/youtube]
lol that's great.

[Gippeto]

Ummm...yeah...okay.

Guess I'm showing my age huh?

[Gun Freak]

Well it's popular in teens and stuff, cause it's so random... and funny... back on subject.
That is a slick looking gun there. Can't wait to see the finish product and some videos!

[maverik94]

Very Nice! Any chance of some damage pics or videos? Also, any chance of a diagram of the internals. (Is it pretty much the same as that one popular crosman pcp pistol I can't recall the name of?

[HunterT]

Crosman 2240 maybe?

[Gippeto]

[quote="Gippeto"]
The only Crosman parts are the barrel (23.5" cut and crowned), barrel band (2240) and the grip frame/trigger assembly(2240). I made the tube, internals, and the breech/reciever assembly.[quote]

And a new pic with the tube and fill plug cold blued and the Grant Stace breech installed (which was NOT made by me ).