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jedi · Member

Does any body know how to mod these: http://www.airgunsus.com/desc/she2909.html for more power/velocity?
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AirGunEric · Site Admin

It's a Co² gun, so any power mods are going to involve gas transfer path a valve modifications. Personally, I'm not familiar with the EB22 specifically, but here's the layout:

Parts picture

Parts list

The springs, part numbers 33 and 15, as well as #13 (which seems to be mislabelled- that is in fact the valve plunger as far as I can tell) need to be modified/changed. Lighter springs and better tranfer are through that valve plunger (i.e. bigger holes).

Perhaps somebody else here has had the EB's apart to be more specific.

Also- Welcome to AirGunHome.com!

The outdoorsman · Veteran Member

welcome and i believe if you mod the hammer spring it will give it more power and you can also do a valve mod if you have a dremal tool

leadman · Veteran Member

switch the hammer spring for a crosman 2289 hammer spring, should bring it up to about 550 fps and about 7-8 good shots

jedi · Member

thanks for the replys guys, but how do I get the valve to come out? Is there a special tool that I will need?
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leadman · Veteran Member

ive never taken the valve out of mine and i realized yours is the .177 model correct?? if so the velocity may be much higher
http://www.crosman.com/2004/pdf/manualarchive/EB-EVP%20&%20PL.pdf
that may be of some help

jedi · Member

Yes thats right mines the .177 version, I`ll have a play around with it and see what happens, Thanks for all your help, people
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jedi · Member

Just a quick one before I fire off into next year, what sort of FPS can I expect from this pistol with the mods using on average an 8gr pellet?
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AirGunEric · Site Admin

Assuming the .177 puts out the same muzzle energy as the .22 version, with 7.9gr pellets, in stock form, you could expect a maximum velocity of around 500fps.

With valve modifications, I think leadman has it about right- 550-ish fps with 7.9gr pellets.

jedi · Member

as standard im getting on average 450 fps so thats around 4ftlbs if my calculations are correct, quite a bit down on the 5+ ftlbs there advertised at, or does the .22 version produce more power?
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AirGunEric · Site Admin

If you look closely at the way velocity stats are stated: "Maximum velocity: 425fps" the key word there is "maximum". Rarely, if ever, do any guns achieve this "maximum". Also, when they test/rate most guns, they use the lightest pellets they can find for the tests ("power" sells). It is quite misleading. Also note, the manufacturers rarely state actual muzzle energy (i.e. 'power') just maximum velocity, so as to make the numbers seem big.

Is this false advertising? Technically, no- but I certainly think it's misleading and somewhat unethical.

Your 4ft-lbs. is definitely within the range anyone can expect for how the gun was likely rated. For the .22 version with a maximum velocity of 425 fps, they probably used 12gr pellets for the testing and did manage to achieve 425fps, or approximately 4.5ft lbs- and you are achieving 4ft lbs- certainly not the "maximum" but also not totally out of the ballpark. If you're using 7.9gr pellets and the gun is outputting 4ft lbs- the velocity would be around 480fps. That being the case- your valve mods may only bring you to around 525fps.

And generally, No, the .22 versions of the same gun aren't any more powerful. This is not an absolute for every gun out there- but usually when two guns are exactly the same except for the caliber- the only things that have been changed are the barrel and the loading port- actual powerplant almost always is the same.

jedi · Member

I see your point, do you know if there is a silencer available for this pistol? or an adapter to fit one?
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AirGunEric · Site Admin

None are made by Crosman/Sheridan- maybe someone in the UK knows of a place or someone who has something available for this gun.

jedi · Member

are the larger calibers more efficient that the smaller ones, I see things like 200 shots in .177 and 350 shots in .22 advertised, for the exact same rifle (PCP) I presume this is the same for co2?
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