12g gram mag effiecncy problems

[cougar20th]

Im trying to get one of my mags running on a 12 gram so i can finish the VSC conversion.

My big problem is that it gets about 5-6 good shots out of the 12 gram then drops fast. The setup is simple so far. CCI 12 gram changer instead of a foregrip. micro line up to the valve. stock classic valve. Any ideas as how to go about increasing the effiency?

[pump]

grease piston oring, check reg pin spring

[Pneumagger]

Im trying to get one of my mags running on a 12 gram so i can finish the VSC conversion.

My big problem is that it gets about 5-6 good shots out of the 12 gram then drops fast. The setup is simple so far. CCI 12 gram changer instead of a foregrip. micro line up to the valve. stock classic valve. Any ideas as how to go about increasing the effiency?

I don't think a mag can run in a VSC fashion though.

[pump]

yeah it can

[ß?µ£ §mµ®ƒ]

Mags already use alot of air per shot, great efficiency from a 12 gram is going to be hard at higher velocities. By 5 quality shots what do you mean? At what velocity and how many total shots can you get? My buzzard gets 30+ shots 25 of which are quality shots from a 12 gram at 250 fps(indoors).

[Pneumagger]

yeah it can

well it can never be stock class I don't think - from a qualification standpoint. you'd have to have a horizontal feed, and I don't think the pumpmag's pump action is a legal stock class pump action.

A pump mag is more of a "bolt reset mag" than a pump mag.

[turbo chicken]

you can

whole thread (http://www.automags.org/forums/showthread.php?t=208650)

... quoted fro rrfireblade


In simplest terms, take the valve body apart and devolumize the chamber. Then re-calibrate the reg to run at higher pressures till you get the FPS you need. . . Cake. ;)

That's a start. :cheers:


You ever run a stock valve on a 12g? :eek:

Even Sydarms are lucky to break 20 shots per cart. ( I have 2 btw) A classic is good for bearly more than 15.

With a complete retune and some additional changes , I'm regularly getting 34-35 shots per 12vie. I think there's a little room to go from stock.;)

Keep in mind , I'm talking about a SC pump configuration. That and I'm used to mid 40s from most of my other pump set ups since I run SC exclusively. Efficiency is more critical.

But it does take some real precise tuning for reliable all around performance.


I'd find something to put in the chamber. I mill a delrin sleeve to fit. You can't fill the whole chamber , due to the blow forward design , chamber pressure drops off quickly as the PT shaft extends. There's one other key that has to be address to take it further. It's really not a DIYer beyond that point. Your going to have to add and chrono and such till you find a good compromise w/ acceptable FPS.

That's kinda the efficiency nut needed to crack with the mag valve design to start with. Now . . . say for instance you had a 2 peice bolt design the changed that relationship between the . . . Uh . . .never mind.


(Drastically scrambles to get the lid back on the can before any worms get out. :ninja: )

[cougar20th]

thank you very much. thats what i was affraid id have to do. Anyone know how to safely split amd reseal a valve like described.

[Spider-TW]

well it can never be stock class I don't think - from a qualification standpoint. you'd have to have a horizontal feed, and I don't think the pumpmag's pump action is a legal stock class pump action.

A pump mag is more of a "bolt reset mag" than a pump mag.

Are check valves allowed? My old mag with a micro CA was pretty worthless on the first 12g, but after you changed out the first one, the check valve helped a lot. Not that I have a vert adapter or twist change with a check valve in it... :rolleyes: (does a CCI have a check valve)?

[DaFin]

Old school stock class = No check valves.

[cougar20th]

well it can never be stock class I don't think - from a qualification standpoint. you'd have to have a horizontal feed, and I don't think the pumpmag's pump action is a legal stock class pump action.

A pump mag is more of a "bolt reset mag" than a pump mag.


Ive modded the body to accept a horizontal feed. Welded a nut to the body and use a cci phantom feed as well as a cci 12 gram changer as a foregrip.

here it is. Please ignore the lack of grips and the pump parts. i have to swap the pump stuff from one pumpmag to the other until i get the rest of my parts from JDogg. the grips i had off for some reason.

http://www.jayloo.com/files/pics/39000/IMG_0947_rs.JPG

why would the pump action not be stockclass legal. theres no chance of autotriggering the thing.

[turbo chicken]

Ive modded the body to accept a horizontal feed. Welded a nut to the body and use a cci phantom feed as well as a cci 12 gram changer as a foregrip.

here it is. Please ignore the lack of grips and the pump parts. i have to swap the pump stuff from one pumpmag to the other until i get the rest of my parts from JDogg. the grips i had off for some reason.

http://www.jayloo.com/files/pics/39000/IMG_0947_rs.JPG

why would the pump action not be stockclass legal. theres no chance of autotriggering the thing.

The last thing you need to worry about is "stock class legal" ... but ill try and elaborate a little

The pump action would need to reset the "trigger/hammer" in order to fire the marker ... on a mag it automatically resets ... you can still in theory fire the gun without having to reset the bolt ... you wouldn't shoot a ball but i think that is what he was getting at ...

To my knowledge every game/tourney that is pump exclusive is pretty broad in what they allow af far a a pump ... usually if it has no electronics or PA and you have to pump it ... you can usually use it ...

The Most Strict "stock class" classifications i can remember are...
Must use 12 grams
No lever changers
Unported barrel
feed tube must be paralled to barrel and touching the body no more than 10rnds (or 12 can't remember)
pump action must reset firing mechinism
No AT

Eh i'm sure i missing some more but that's the idea ... I've there are a few more things i have seen that aren't listed ...

[SR_matt]

ya old school stock class rules are very strict but as things evolved they got a lot mroe lax. heck now at this point is SC if it uses 12ies and a stick feed.

if you can find a group with enouhg pump players to have large games or a small tourney with then you can start worrying about enforcing harsher marker guidelines

-matt