Air Gun Home :: View topic - Crosman Phantom 500

vAgRaNt · Member

Has anyone disected one of these yet to determine what the internal differences are between it, and the others in the family - 500x.22/ 1000x.177/ 800x.22 ?

Would it be more likely that they added another ~2" to the 500x.22 piston, or further reduced the spring dimensions?

What are the experiences of people here regarding Phantoms being "seal eaters"? Do I need to order a half dozen seals before I pick up one of these things (500x.177)?

Is the 1000x.177 a reasonably sedate shooter similar to the 500x.22, or is it a fire breathing, hold sensitive monster like some other "magnum" rated guns?

Yea I know, I could just buy a 1000x.177 and be done with it, but where's the fun in that? I really enjoy "shooting", but as I'm only a mediocre shot at best, much of the enjoyment of this hobby is in the "shade tree" gunsmithing. I wouldn't know what to do with a gun I couldn't fuss with a little. . . . . . Laughing

Any and all perspectives appreciated - and when I pick one up and rip it apart, I'll use this thread to document my findings.

TIA.

[shudder] - newbie questions - [/shudder] Mr. Green

AirGunEric · Site Admin

Despite the fact I've had most of the "detuned" Crosman's of this platform apart- the newest .177s have eluded me thus far. I have shot them, but not ripped into them.

The newest detuned .22s have a "full power" spring in them, but the piston is elongated about 2" (there's a thread around here somewhere with the exact dimensions) cutting the cocking stroke short.

The detuned .177s have more done to them, having fired a couple, they are obviously weaker than the .22s. The answer should be apparent- a .177 pellet weighs -roughly- half what an equivalent .22 pellet weighs (i.e. 7.9gr vs. 14.3gr) and as both caliber detuned guns are detuned for velocity (495fps) not overall muzzle energy, something more than just the piston length is different. Elongating the already long piston from a detuned .22 would be pointless- cocking stoke would not be the roughly 1/2 way down stroke on the barrel, more like 1/4 of the way down and it would be both disconcerting and silly with a cocking stroke that shallow. Also, the two .177s I test-fired had about a 1/2 length cocking stroke- so even more extended piston length is not the answer here.

SO- the .177s must have the lengthened piston like the .22s and either no rear thrust washer (eliminating about 1" of spring pre-load) or the spring is shorter/weaker.

That being said- when the detuned Phantom first appeared, it had a spring- while of the correct "full power" specifications- had a narrower inner diameter- meaning the top spring guide and rear thrust washer were narrower than those found in the non-detuned versions (there is another thread around here somewhere showing this). So- using a "full power" spring in the detuned Phantom would be possible (albeit for no practical purpose) but there would be slop around the tophat and rear thrust washer. So, a spring, top hat and thrust washer would have to be used from a full-power rifle. Then throw in that the rear thrust washer's inner diameter was different on the detuned Phantom than those found on the full-power rifles, and it would need to be changed as well to use the thrust washer. Confused yet?

Crosman refused, despite being presented with the evidence via photographs, that there were in fact these differences and claimed that they "might" only existed due to machining tolerance issues. Bullsh!t- but whatever, they obviously weren't too interested in investigating. So- if you needed to replace your detuned Phantom spring, there was no specific detuned Phantom spring available and the full-power spring would be too wide on the inner diameter- leading one to have to purchase the parts mentioned.

Now, Crosman has made more changes to the Phantoms/Quests in the last year- a more resilient breech seal and (in some rifles so far) a metal rear thrust washer, not resin.

The two .177 detuned rifles I tested were shipped with tune-up parts, and the owners were going to get back to me on what they found- but I never heard back on them. So- I currently cannot say if the newest detuned .177s need just the piston and spring, or the piston and rear thrust washer, or the piston/rear thrust washer/spring/tophat and rear guide.

hoo- now I'm getting tired.

If anyone wants to buy a detuned .177 and let us know what they find, that would be great. Heck, if anyone in Canada wants to buy a detuned .177 from http://www.scopesandammo.com and let me take it apart for them, I will determine what is required for a tune-up. I don't do tune-ups, but I can determine what parts are required.

As for replacement piston seals- some of the ones that come out of brand-new rifles are pretty 'iffy' due to poor assembly. Sometimes pulling the piston/seal out causes damage if the "tuner" isn't careful. It's always a good bet to get a spare seal (one or two- not 10). That being said, if one wanted to hone the tube (a 1" ball hone found at any industrial tool supplier and an extension rod added to it to get the required length) they can eliminate seal disintegration due to roughly machined tubes. Old age and detonation that could kill a seal would still be possible, but the mechanics that could rip a seal would be eliminated with a honing- and the overall seal to the tube would be improved after a few hundred shots as well.

aarrgh- that was alot of typing! Mr. Green

BCSteel · Member

I have the two phantoms in sub 500 fps factory stock, one in .22 and one in .177 but I have not had them both apart at the same time nor do I have calipers to take any measurements of their differing parts but here is what I have noticed.

The pistons appear to be the same in all dimensions but like I said, I have no calipers.

The springs are different. The .22 is a thicker wire and has a little more preload, probably due to the added force of the heavier spring. There is very little preload on the .177 spring.

Seals. In my .22 I have well over 5000 shots and the seal is holding up fine. Its a little worn but still seals well and I have not noticed a drop in poi at the longer ranges (50 yards and over) as I've had the same zero point for at least the past 3000 shots or so.

I only have about 700 shots through the .177 but the seal looks like new.

I lopped off a couple inches from my .177, added a couple washers and kept the stock spring. I have no chrony but using this velocity estimator http://www.airgunexpo.com/calc/calc_mve.cfm? it says I'm up in the high 8's. Shouldered snug and held fairly firm, it keeps its poi well.

Like I said, I have no measurement tools but shoot lots when I get the chance so take it for what its worth.

BCSteel · Member

AirGunEric · Site Admin

You may very well be correct- on the "original" Quest 500's (detuned .177s) the spring was different as well.

Your breech seals- what color are they in each rifle? They originally were black and slightly softer, the newer ones all appear to be white and made of the same material as the piston seal (i.e. more rigid and tougher). Also- how old are your .22 and .177?

BCSteel · Member

Breech seals? Clear on both of them.

Age - .22 is about a year old from walmart and the .177 is just a couple weeks from crappy tire.

Slavia · Moderator

I got my G1 from Walmart in March or April - breech seal is similar to the piston seal.

BCSteel · Member

I had both of my phantoms apart today to swap springs when the one in the .177 broke. The only difference in power plants between the two in their sub 500 fps form is the springs and thrust washer (.22 being plastic and the .177 being metal). The spring from the .177 is 30/31 coils and the one in the .22 is 36/37 coils. There may have been a difference in wire diameter but I could not see it. The tophat, piston, rear spring guide and rear thrust washer were all the same in dimensions and fit equally as sloppy from one gun to the other.

AirGunEric · Site Admin

Aha! So it is just the spring, really. The plastic vs. metal thrust washer is a -date- thing, the newer rifles are obviously getting the newer (metal) washer- but they should both be the same size.

Thank-you for the confirmation on what I had suspected!

dorikaze · New Member

I would suggest you to get rid of the spring that comes in them and up grade to this one http://www.airguns.citymax.com/catalog/item/251488/43410.htm
its about 17.00 USD pls shipping. This will increse you FPS and should not brake as easly, but watch out when installing the new spring it longer and a bar clamp will sort of work,

daniel boone · New Member

Hello all.
Im new to this forum but I love air guns and own 2 of these crossman phantom 500's. one in .177 and the other in .22. I have taken the both of mine apart. also bought the parts for the quest 1000 like spring and piston so all at one time i could change it all. Guess what!! parts are the same!! here is where the only difference came in. There is a hole drilled into the back wall of the piston alowing some of the air to be blead out to just behind the spring. i drilled it out but only half way through so i could fill the hole with a piece of lead shot and jb weld. It worked perfectly. Of course I tuned the rest of the gun before putting it together also. I have a crony and with standard pellets on the .177 can get 950 fps and with the light pellets get 1050-1080 fps. with the .22 can get with regular pellets 850 fps and with light ones 920-950 fps. Not bad for a walmart $ 99.00 regular price gun. I have a scope on it and can consistently get a 5 shot group that can easily be covered with a loonie at 25 yards.

Just to let you know, I did buy that tarantula spring you mentioned. infact I bought 2. after the first shot the spring is bent. There was alot of preload that needed to be applied as in about 4" worth. after that aim went wonkie as spring is probably flopping around. fps didnt seem to be much better. Any thoughts?? I have 1 more spring to experment with?? also the actual wire diameter is .116 with a micrometer. Is there a tolerance factor?? also with that much preload..... should i cut it a bit shorter?? if so, how do I do that. The pic that I posted has the hole drilled through the back of piston. I think that if crossman gets the same parts for all guns and only needs to drill a hole in the de tuned units that its probably cheeper for them. the second pix is origional phantom 500 and 1000 spring as they are the same. and the longer by 4" is the tarantula spring.

Also, whats a good seal to use on this gun?? i want a couple of spares.

Thanx for reading my first post.

Daniel Boone

AirGunEric · Site Admin

Aftermarket springs are a waste of time in this platform- the maximum power available is determined by the swept volume of the chamber- which cannot be changed by the use of a super long/rigid spring- the stock spring in the "full power" 1000 versions works fine- at absolute best the aftermarket "performance" springs might give an additional 3% of power- which you could also get with minimal shimming of the stock spring.

Referencing 2+ year old posts for information is not really a very good idea- things may have changed since the post was "current".

Also- where did you get these numbers: "with standard pellets on the .177 can get 950 fps and with the light pellets get 1050-1080 fps. with the .22 can get with regular pellets 850 fps and with light ones 920-950 fps" this is, no offense, bullsh!t- the platform cannot move enough air to get this amount of energy out of it. If in fact these number came out of a chrony- it either needs recalibrating or you are having detonation problems.

daniel boone · New Member

Sorry about posting on a old post. Didn't realize as new to the site. As for fps, numbers are true with a standard crony that seem accurate with all the other guns I shoot through it.

AirGunEric · Site Admin

Something is not right- the tube does not contain enough air to move standard pellets at that energy level. You likely have a detonation issue. Put 500 or so pellets through one of the rifles, keep petroleum oils away from the chamber and then re-test- if you didn't slather the internals everywhere with a petroleum grease, the lube should be out of the chamber by then. Only put a pure silicone oil (no petroleum products in it) into the chamber to lube the seal. Detonation may also explain how that spring bent after only a few shots.

kanyon · Silver Status Member

hi...
the 500fps Quest had a hole drilled though the piston
to let air out... if its one of these models...plug the hole.