Help making a pump gun

[CGPro856]

I have this. I don’t know anything about it but I figured I’d make a pump gun out of it. What do I need? What do I need to know? TIA

[Cdn_Cuda]

You need a pre-2k Mini pump kit. https://autocockerparts.com/slice-pu...ini-slice-kit/

[CGPro856]

Thanks. It looks like the mini kit has a vertical asa that will allow me to install a LPR. Is that correct? And if so, what is a good operating pressure for one of these? I’m assuming springs make a difference but what is a good place to start.

[Cdn_Cuda]

Yes, it was a VASA and you can use and HPR or run a bottle directly. I’d assume that marker has the original internals. You can upgrade the valve and springs and either thread the body for a standard threaded IVG or get an adjustable threaded IVG. I have a thread on pre-2k cockers that cover the internals. I’ll dig it up.

[Cdn_Cuda]

Check out post 5 and on for the internals:
https://www.mcarterbrown.com/forum/p...pre-2k-cockers

[latches109]

It will make an excellent pump. If you want to go sniper 3 style, you will need pump over barrel handle, pump arm and some way to feed it air. On a side note I’ll buy or trade you your front pneumatics for another build it have.

[latches109]

https://airsoldier.com/product/asp-pr6-phantom-pump/

[Psycho91]

Tha handle is pretty slick

[CGPro856]

Cool, I didn’t know that it could run straight off co2 or hpa at HP (850psi). I was told it needed to be closer to 350psi and had originally used some type of reg that I’d never heard of. I was trying to tune it with my LP HPR at about 400psi and it would cycle and shoot but not well.

I’ll pull it all apart after work today and post a pic of all the guts.

[latches109]

You just need to change your springs. Higher pressure stiffer springs.

[CGPro856]

Had a few minutes this am. Here’s what I’ve got.

[Cdn_Cuda]

Ah, that's good! You have the adjustable IVG already, so that makes it easier to work with. You have an older style valve in it as well, which is useable, or you can use a standard cocker valve. Best bet is to try if first and modify it if you need to. The hammer slot likely will not take a standard cocker hammer as the slot will be too narrow to for the new-style lug. I believe i cover this near the end of that thread I posted.

[CGPro856]

Who made this body? 1601 seems like a low serial number. What year was this made? What about the bolt? I’m guessing it is aftermarket. It’s aluminum, stamped G-1 and has a spring loaded separation in the middle. What can you tell me about that?

[Cdn_Cuda]

Likely an early WGP body. Apparently they remembered mini bodies, so they are hard to date. looking at the internals, similar to my ‘96 cocker.

Can’t help with the bolt either, other than confirming it’s an aftermarket bolt.

[CGPro856]

It will make an excellent pump. If you want to go sniper 3 style, you will need pump over barrel handle, pump arm and some way to feed it air. On a side note I’ll buy or trade you your front pneumatics for another build it have.

That is a very cool look but I think I’ll go standard pump
for now. I’m going to hang onto the pneumatics for now too. Just in case I ever find the need to play an OG autococker game.

[Jordan]

Who made this body? 1601 seems like a low serial number. What year was this made? What about the bolt? I’m guessing it is aftermarket. It’s aluminum, stamped G-1 and has a spring loaded separation in the middle. What can you tell me about that?

Minicockers have their own serial number series, separate from full size Cockers, so while it's old, it's not that old. Probably early to mid 90's - no threaded IVG so it likely started out with the older Sheridan-type mainspring. WGP went Nelson-type springs in '98.

IIRC, those bolts were supposed to help with blowback up the feedneck - the spring in the middle creates a small delay between the backblock moving and the bolt tip moving. In practical applications, all you get is a timing headache. 🙂

[CGPro856]

So I need some more help. The pump kit came in and I put it together. It works just fine but my velocity is all over the map. I have tried different valve springs I have tried different hammer springs. It seems like my first shot is low and then it climbs and climbs, and climbs on every shot, for example the first shot will be 240 the second will be 260 the third will be 280 then 300 310then 320 and then it just hangs around 320 until the CO2 runs out. if I back the velocity screw out, it will start lower, but still ramp up to 300+ every time. I’ve gone through a dozen CO2’s and I can’t figure it out. I will try it on HPA but the slice pump kit VASA doesn’t have a pin to open the regulator on the HPA tank and I don’t have a set up at the moment to rig it up.

[Alexndl]

You where using a 12g for your CO2?

[Chappy]

Sure seems like you need a reg like your initial thought. Sounds like unregulated co2 is overpressurizing the valve.