The as2250 King Ratcatcher is back

[Tack Driver 10]

Ninja bottle arrived this afternoon along with a few machine bits so finished up the adapter.
The final adapter is just under 1 1/2" long and with the 13 ci bottle and on/off, the LOP is 15 1/4".
With the 9 ci bottle the LOP is 13 1/2", good for young shooters.

[2K1TJ]

Nice work!

[Tack Driver 10]

Soooo, just to clarify, there are actually two RatCatcher guns.
The top gun is the original converted pumper.
Should get to test it with a regulated bottle later this week.
Ordered a $50 China floor pump, should be here in a few days.

The lower gun is the new kid on the block.
It's going to be a dedicated bottle rocket gun.
Pictured mocked up with various parts.
Currently a work in progress.

[Tack Driver 10]

The new kid scoped with a 14" LW barrel.
Need to cut the tube back a few inches to make room for a "Big Honking Can", otherwise very nice.
Tipped the scale at 5 lbs as shown.

[Gertrude]

Looks nice.
Kind of the same thing l did to a few 2240 PCP conversions.

[Tack Driver 10]

Looks nice.
Kind of the same thing l did to a few 2240 PCP conversions.

Do you have a link?
I'd like to know what pressure and velocity you're making.
I'm going to reg this gun at about 1200 psi.

[Tack Driver 10]

Cut 3 1/2" off the front of the 2260 tube.
Got the valve done and assembled the tube to test for leaks.
Popped in a CO2 cart and it's sitting with about 900 psi on the gauge.

Used the back portion of an MK177 valve with a brass top.
Punched it out to .500" and cut a concave seat.
Located the input from the tank close to the Delrin stem for max flow.
Stock .200" throat with a .170" ported TP.

[Tack Driver 10]

The China pump arrived yesterday, $50 to my door on EBay, Wow.
Listing stated 6000 psi but I doubt that's attainable.
I was thoroughly impressed with the quality except it didn't have a port for a desiccator.

The input is at the top of the tube under the handle so made a new handle.
It along with a spacer made of peek corrals a user added o-ring seal with a port out the front to attach a desiccator.
With the desiccator on the input side it eliminates the filter on the fill hose.
Need to make the desiccator now.

Pumped up the 9 ci bottle to 1500 psi leaving the reg stock at 800 psi (showed 700 on my gauge).
The reg in the 13 ci bottle was adjusted to 1200 psi and pumped to 1500 psi.
Should be able to do some tests next week.

[Tack Driver 10]

Made a temp desiccator from acrylic tube from another project.
I'll get a shorter 1 1/2" acrylic tube for the final version.
Simulated the desiccant with rolled up blue paper. 

[Tack Driver 10]

Time to do some testing.
Ran 2-3 shots per bottle straight off the bottle load.
Both guns use the same breech/20" barrel/hammer/stock 2400 spring.
Very easy to rack, about 10 lbs.

Ran Gun #1 first, the modified pumper/HPA gun.
Not expecting big power from this gun as it has a small valve volume.

Gun #1 the modified pumper/HPA gun.,
09 ci bottle, reg 800 psi, CPHP 14.3
527 FPS 8.82 FPE
529 FPS

13 ci bottle, reg 1200 psi, CPHP 14.3
666 FPS 14.08 FPE
663 FPS

Gun #2 the dedicated HPA bottle gun
09 ci bottle, reg 800 psi, CPHP 14.3
583 FPS 10.80 FPE
588 FPS
587 FPS

13 ci bottle, reg 1200 psi, CPHP 14.3
716 FPS 16.28 FPE
709 FPS
712 FPS

Pretty good right out of the mod gate.
Some tuning and more mods to come.
Gun #2 mocked up with various parts.
Shoulders and sights up nicely, balances at the loading port.

[Tack Driver 10]

Guns have a 60 gram SS hammer and 2400 spring in it and it racks good but still lacks the silky smoothness I'm after.
Took a 13xx hammer and encapsulated it in Delrin weighing in at 44 grams soaking wet.
I call it my "Pigs in a Blanket" mod.....LOL

Attached the 13 ci bottle at 1200 psi 2 shots with 14.3 CPHPs.

694 FPS 15.29 FPE
693 FPS

Dropped about 20 FPS but now I'm a smooth operator (you know, like the song).....LOL

[Tack Driver 10]

Desiccant and acrylic tube arrived so made the desiccator for the pump.
Used 1/8" felt for in and out filters, Delrin for the caps.

Also made a transfer tube from Delrin.
I like the look, the Blackout version of the Ratcatcher....LOL

[Tack Driver 10]

Cut the tube, made a moderator and fore grip.
Gun is 35" as shown with a 14 1/2" barrel.

[2K1TJ]

Looks great! I like how the forearm turned out.

[Tack Driver 10]

I like it too, it's made from ash square table leg stock form Lowes.
Stained with Minwax ebony stain and has a bronze cast to it.

Time to address the elephant in the room.
That's right, it's "Hammer Time".
Since there's no place for an external velocity adjuster made this internal version.

Modified a stock hammer into a sling shot hammer.
Drilled the center 1" deep x .400".
Sleeved it with brass, weighs 52 grams.
Filled the waist of the hammer with JB-Weld/steel wool.
Pressed on a Delrin ring on the back so it'll slide smoothly, sits proud by .007". (like the secret agent)....LOL
The spring assembly is self contained using a cut 2300 spring.

[Tack Driver 10]

Beefed up the moderator and made a new valve.
Tried a long valve with a monster plenum and external valve spring.
Too much wasted air so ditched the extra length.

The gun has the excellent 1701 trigger pack but I opened up the trigger blade a bit.
With the slingshot hammer/spring, ran it over the chrony.

With 1200 psi on the regulator and a 17 cal 14 1/2" LW barrel:

7.90 CPHP  777 FPS 10.59 FPE
9.57 BHE    741 FPS 11.67 FPE

Pretty good, right where I want it.
Would like to try a 22 cal barrel next.

[Tack Driver 10]

Time to try a 22 cal barrel on the gun.
With 1200 psi on the regulator and a 22 cal 14 1/2" LW barrel, .130" barrel port:

14.30 CPHP  616 FPS 12.05 FPE
18.52 BHE    567 FPS 13.22 FPE

Opened up the barrel port to .157".
14.30 CPHP  662 FPS 13.87 FPE     
18.52 BHE   603 FPS 14.85 FPE

25.40 JSB    534 FPS 16.08 FPE
33.95 JSB    467 FPS 16.44 FPE

I'll probably leave the gun as it is except for some minor tuning.
Here's a picture of the final version and the specs:
Weight 4 lb 9 oz  no scope, 5 lbs 14 oz scoped as pictured
Total Length 34"
Barrel 22 cal 14 1/2" LW
LOP 14 1/2"
Regulated 9 ci bottle @ 1200 psi
78.6 dB @ 36" from muzzle with pellet fired

Have this to make it a multi shot gun:

[Tack Driver 10]

Made a new hammer with a brass core in a Delrin tube.
Has an adjustable center screw to limit stem travel.
Adjusted stem travel to .095".
Weighs in at 40 grams.

Ran the gun over the chrony, regulated at 1200 psi, performed same as the 52 gram hammer.

Made a new plenum but not as large as the previous MONSTER PLENUM.
Gained around 1 1/2 FPE over the stock plenum with the 14 1/2" LW barrel but was wasting air.
14.30 CPHP  699 FPS 15.51 FPE
18.52 BHE    636 FPS 16.63 FPE
25.40 Mnstr  567 FPS 18.13 FPE
33.90 Beast  498 FPS 18.66 FPE

Bolted on the 20" Crosman barrel and crony tested:
14.30 CPHP  768 FPS 18.73 FPE
18.52 BHE    707 FPS 20.55 FPE
25.40 Mnstr  626 FPS 22.10 FPE
33.90 Beast  550 FPS 22.77 FPE

Should get around 80 shots from the 13 ci bottle with this setup, 3000->1200 psi.

[Tack Driver 10]

Made a new plenum and bumped up the regulator to just shy of 1400 psi.

With CPHP 14.3
772 FPS 18.92 FPE

With Barracuda Hunter Xtreme 18.52
700 FPS 20.15 FPE

Adjusted the hammer so stem travel is reduced to .060" from .095".
With CPHP 14.3
750 FPS 17.90 FPE
80 dB measured at 3 feet.