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AirGunEric · Site Admin

I don't think such a modification would make the piston too weak for it to hold up. Where it wouldn't work would be that when in "1000fps mode" the piston wouldn't have enough room to travel to get the trigger to grab the "1000" slot- the end would bang into the rear spring guide. I didn't actually measure how much clearance there was between a 1000 or cut piston and the guide (or the end of the tube)- but it wasn't a whole lot- looking at the gun's trigger placement vs. the pin in the tube- maybe 1" maximum. So, your mod could work, but it would require the removal of the rear guide and it wouldn't be a 500/1000fps deal, probably more like 500/700fps.

Mar · Veteran Member

You kind of lost me with the rear guide thing. If you cut the piston a la 1000 piston, such as making the slot longer as on the 500, this rear guide could get in the way???

Wait...I think I understand what you are saying now. You're saying that breaking the barrel the piston may not have enough backward travel for the trigger to engage.

Yeah, you could be right about that.

Mar · Veteran Member

Ah you're right once again. I just checked it visually and it wouldn't work now that I see it.

Too bad, it would have been kind of a good idea if it worked.

Glad I ask first and thanks.

Greenangel · Member

I don't think that would work because by cutting it down you are making it able to travel further back in the chamber that holds the piston
basically what you cut off is what you gain in travel distance which equals more power

Mar · Veteran Member

Yeah I could see that when I got to cleaning it out and all. First time I ever took a springer apart, I really need to work on my compressor project.

Mar · Veteran Member

So I kind of wreck my piston seal and D&L doesn't stock them yet.

Would one for a quest be the same? Where might I try to get a new one?

AirGunEric · Site Admin

The Quest seal is the same. The Quest 1000 seal and piston (they come together) would work too.

To find them in Canada, the "official" Crosman parts vendor is The Gravel Agency in Quebec, but you can also talk to Airbuddy3 here- he has seals he sells with his springs- so I'm sure he can provide just a seal by itself (these seals alone were never super-cheap from Crosman- like $5 or so, so I don't know what the slightly harder seal from AirBuddy would cost).

The owner of the former Crosman parts depot sent me a note a couple weeks ago that he still had inventory on some parts and thought maybe he could offer them up to people here- so I responded "OK- good idea" and I never heard back from him(!?!). You could try PM'ing "nooblou" and see if he responds to anything.

Mar · Veteran Member

I placed an order with Gravel about a month ago, recontacted them a couple weeks ago and still not have a clue if they are doing anything but tell me everything was order and awaiting shipment. They suck with the customer relationship, blah,blah, blah.

Thanks for the other links though.

Do you think because I screwed up my seal that my POA is affected that I have a hard time hitting a dime size target? Seems that way at the moment but maybe I'm not seeing straight at the moment. Smile

I figure I'm getting variance in power output because of it.

Is "nooblou" a member on here?

AirGunEric · Site Admin

Yes, 'nooblou' is a member here, and thus how he had contacted me about offering his remaining Crosman parts up for sale. I have no idea what happened to him after that, though- he just seems to have disappeared.

johnnystecchin0 · Guest

the 495 fps piston dimensions are:
1. distance to start of long slot from piston seal-end edge: 56mm
2. distance to end of long slot from piston seal-end edge: 123mm
3. distance to start of short slot from piston seal-end edge: 179mm
4. distance to end of short slot from piston seal-end edge: 185mm
5. distance to end of piston from piston seal-end edge: 191mm
6. large slot width 10mm (or 3/8in)
7. small slot width 9mm (can be 10mm)

the mod piston, based on actual piston measurements:
1. distance to start of long slot from piston seal-end edge: 14mm
2. distance to end of long slot from piston seal-end edge: 125mm
3. distance to start of short slot from piston seal-end edge: 133mm
4. distance to end of short slot from piston seal-end edge: 139mm
5. distance to end of piston from piston seal-end edge: 145mm
6. large slot width 10mm (or 3/8in)
7. small slot width 9mm (can be 10mm)

notes:
1. large slot is assumed cut with a mill or burr bit, use 3/8 bit so large slot ends are semi-circles. above distance to semi circle outside edges.
2. mod piston NOT "50"mm or 2 inches shorter, it is exactly 46mm shorter.
3. long slot is exactly 42mm longer (towards the seal-end of the piston).
4. yes there is a 4mm discrepancy between total piston length shortening and large slot extension, that's the way it is.

Shakeyupnorth · Member

The Phantom seems like an awesome funmachine and I have seen the piston chop work wonders in about 45 minutes of careful metalwork, but a properly (albeit Chinese)heat-treated and dimensioned piston might be stronger and prove a wise investment given the reasonable price. Maybe use the chop job until a replacement comes in the mail...

AirGunEric · Site Admin

rodless · New Member

I cut my piston a little more than 52mm (2mm more than i should have) and that is the most you can cut off. Now It cant even be spaced with washers or it simply will not cock. The phantom now packs a punch.

johnnystecchino · Guest

Agreed nothing beats the OEM right part. Just wanted to put on paper the dimensions of the right part.

as for lube, i am using a very thin coating of Fluid Film. So far, OK.

johnnystecchino · Guest

Does anyone know of a gas ram piston that can be used in the phantom?

ciao,
johnny.