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AirGunEric · Site Admin

Yes- the Air Venturi spring used for the Gamo Whisper:

http://www.pyramydair.com/cgi-bin/accessory.pl?accessory_id=2103

How do I know it will work? I don't- Tom Gaylord makes this claim here: http://www.pyramydair.com/blog/2007/12/cleanup-day-silver-eagle-pellets-for.html

Sixth paragraph down the page under "gas springs".

But, the gas spring costs more than the Phantom- is it worth it? Maybe- I've never seen anyone who's tried in on a Phantom- so you could be the first!

Anyone know who "Air Venture" is? It might be nice to find their website and see who else carries the gas spring line-up

johnnystecchino · Guest

it's worth it. Kind of like polishing a diamond...

johnny stecchino · Member

Would anybody have any pics of their gas ram installation, how you did it, any tips or tricks-of-the-trade you might share? I would really appreciate hearing from you!

Thanks,
Johnny.

polyo · New Member

Just modded my Phantom and she really cracks now! One shot went 3/4's the way through a 2x4.
However groupings don't seem not as tight anymore.

Can anyone relate their experience as to accuracy after modding the Phanton 500 .22

My Mod: Piston - 49mm cut off
Lube - Moly on piston and silicone lube in receiver

Also added Harris bipod and mildot scope.

AirGunEric · Site Admin

Try using another type/brand of pellets and see what happens. Don't use super-light pellets now that the output has increased. The power increase alone did not affect the barrel in any way- right? Therefore it must be the pellet's reaction to the increased velocity and air. Either that, or you may have had more wind to deal with after the tune-up was done than beforehand.

The other option is, of course, that you are not yet accustomed to the increased recoil- so try adjusting your hold.

polyo · New Member

Thanks, on next low-wind day I'll try that out. I suspect my grip is the culprit as I use my non-trigger hand under the butte for maximum stability when aiming while using bipod. (in both prone & bench top positions)

CrossmanInstructor21 · New Member

IMPORTANT!!!!
The Phantom 500 available at Canadian WalMarts as of June 2010, is NOT adaptable by this method, as the piston is already the same as the 1000 piston! By cutting it, you will NOT have the necessary clearance to extend the channel, as it is already up to the seal!
In short, you won't be able to close the rifle and therefore it becomes unusable.
I believe it is the spring that is weaker in these rifles so as to make the 495 fps rating as there is nothing else than can be modified.
This was an expensive lesson for me to learn, so DO NOT DO THIS MOD IF YOUR RIFLE IS NEWER THAN JUNE 2010 IN CANADA!

Dukemeister · Member

Slavia · Moderator

Try completely removing the bipod. They talk about the "artillery hold" with springers, where you hold it as lightly as possible and let it rock in your hands. The bipod could be rigid enough to prevent the gun from moving (sandbags can have the same effect).

I had a similar bipod on my Crosman G1 (although mounted on a sling swivel stud under the stock). I wasn't happy with the gun's accuracy until I went to a Ram-Line plastic clamp-on bipod. It's essentially a glorified clothespin that clamps on the barrel just ahead of the breech block. That one works for me, maybe because it is wimpy and wobbly:
http://www.ram-line.com/acc.aspx

If you really, really like the current setup, another thing to try is changing the position of the bipod on the barrel. It could be interacting with the barrel's vibrations. You probably can't go backwards (not enough clearance with the stock to cock it), but try moving it forward 1mm at a time and check your groups.

AirGunEric · Site Admin

At the time this topic was current (2007/2008) it was accurate. As mentioned, there are a couple detuning methods now in use- longer piston and vented piston.

On all "versions", the .177- both the piston and the spring have been modified from the '1000' version. In .22, only the piston has been modified.

I am unclear how CrossmanInstructor21 had an expensive lesson here? Did you take a shortened piston and shorten it some more? If you got the information on this here- the very first post states the piston lengths that were used- so this could have been avoided.

GuitarMan · New Member

AirGunEric · Site Admin

Plasticman · Member

Thannks to all who posted here. I bought a Phantom 177 and did a tune from the information on this thread. All went well for me as I just cleaned up the gun and relubed it. On the piston I have the short one with the hole in it which I thereaded and can now put in a set screw if I want to make it a pal gun. Iwish I had bought the 22 but there wasn't one available at the time now I will probably own two Phantoms soon.

hawk900 · New Member

I just picked up a phantom 500 at walmart and it does have the exact piston as the 1000 and yes there is a bleed hole in the end of the piston to let the right amount of air out to keep it under 500fps. I took a drill bit slightly bigger than the tiny air bleed hole and drilled just a tiny way in to create a funnel effect. Then I filled the funnel hole with j and b manifold crack sealer that can seal 3000psi of pressure and pushed it into the funnel/slash hole with a butter knife until I noticed a tiny bit off sealer coming through the underside of the piston head with a flash light. This was performed with the seal removed and the entire piston degreased with pro brake cleaner
Now it has a true 1000 piston in it. The spring also is still a thinner wire coil but 1000 length . Can someone refer me to a stronger aftermarket spring with matching ID or just a high performance after market spring that has matching od spring guides(top hats) designed for 1000 quest or same compression tube size models.
I just don't know any of the high end after market high pressure spring names or manufacturers or sites to order them.
Will keep you posted when I find a strong spring.
hawk.

SMP · Silver Status Member

Sure can

Send this fellow an email using the "contact us" feature. He will fix you right up.
http://scopesandammo.com/storefront/