Here is a air soft modification that is simple and will increase the muzzle velocity. The gains are moderate but if you have to disassemble your CYMA or similar air soft pistol any way, this Instructable will help make your gun a little better.
I bought this pistol for under 10 bucks and was surprised at it's accuracy at short distances. Surprised a few squirrels and other vermin with it. I being cheap also put some mini paint ball ammo through this CYMA P.638. Bad idea! The paint ball ruptured in the breech gummed it all up. Now I have to take it apart and clean it, so here we go..

Step 1: Disassembly

First we must take it apart. The arrows in the photo show where the screws are that hold it together. The orange outer barrel cover is glued on so be careful don't try to force it off or apart.
This modification will use one flat washer 1/2"diameter or 13mm., and one 7/16" nut. Utlilizing the original spring but increasing it's compressed energy so it will release more energy when it expands. See photos below.
I grew up using Daisy Red Ryder lever action BB guns for what you are doing & those old Daisys shot so slow that you could watch the BB go, but they still stung to get hit by.
CYMA SUCKS!!!!!!!!!!!
the aks are decent, especially for beginners
they've started coming out with Tokyo Mauri clones that are very good
oh yeah, what gun do you have? mines a G&G combat machine m4
a Team SD M14 spring, 400 fps
mines around 360fps but Im okay with it since it still shoots very far and accurate
electric or spring?
electric, and it shoots around 15rounds per sec. with an intellect 8.4v 1600mah battery
how much did it cost?
wow this conversation lasted many months lol
indeed<br />
i ahve the same gun the red dot site it comes with is very inacurate and all around its pretty inacurate even with .25s! but its strong for backyard wars wich is all i need and i can snipe sorta
wow that gun sucks my............ i have jg 614 that shoots 415 fps
the m14 costs 30 dollars and shoots 400 fps, soo....
sorry to tell u, but i bet it definitely is not 400 fps.. have it cronned and send me a pic when it is cronned. :)
<a rel="nofollow" href="http://pyramyd-air-guns.com/M14-Sniper-Spring-Airsoft-Rifle-Combo/M/B001ENIHYI.htm?traffic_src=FIND&utm_medium=organic&utm_source=FIND&affId=the005-20">here</a> it says 380 with a .12, and it's crono'd, but if you lubricate the barrel, it goes almost 500<br/><br/>
NO WAY IN HELL that gun will ever hit 500 even if u get a new spring... i have it (as one of the first guns) what do u mean "lubricate the barrel"...
he said "almost"
dude dont comment... i have the gun... and the max it goes is 300-350
You have a chrono? Oh ok my bad. Because if you just had the gun there would be NO way of knowing.
lol.. i have 3 different airsoft guns and my bros have another 2. they each go different speeds.
Are you slow or something? what does that have anything to do with the comment I posted? Gun descriptions aren't reliable sources for FPS, either you have it verified by a chrono, or youdon't know the FPS. Thats it.
you don't know what lubricating means? as in put lubricant in it? less friction in the barrel means the bb goes faster...
it will stick the barrel up
um... no it won't...
lol... it will.. wat did u use?
airsoft lubricant.... it doesn't get any clearer than that... have you ever even used the right kind?
LIKE: WD40. wat did u use? they sell airsoft lub?
airsoft lubricant... are you slow or something? no offense...
well we dont want really strong guns that hurt to bad and my moneys tight so it would be nice to have a better gun but for now this is good enough and besides i just started
isnt that the point of the game? hurt the opponent? 415 fps leaves a welt from about 20-50 feet. the closer you are the more painful it gets. but you will get better because then your trying not get hit. my gun was 150-170 dollars. i had like 3 cruddy guns before and it is so much easier to have a durable and more expensive gun.
i know and for where we play most of our guns our good but we just play in backyards or just shoot targets so it dont matter to much and i want another airsoft gun but my parents wont let me get one for a long time
yeah at first i couldnt get a gun... took a while. i play with a couple friends we all have decent guns.
Their aks are decent... i have an e1 g36c and hope to get a KWA NS2 usp compact for my birthday april 17th...
on the box it says "last selecting". does that mean this gun is the bottom of the barell, quality wise, as in "last picked"? the translation on some of those airsoft gun boxes are a riot.
Not sure sir, the translations are quite entertaining some times. Sorry for the delay.<br />
for the record you never wanna use airsoft paintballs in a spring airsoft gun only use them in co2 and green gas guns if you get paint stuck in you gun private message me and i will post an instructable on how to get it out in less than 5 minutes and with out taking the gun appart
Great im pretty into airsoft and i needed something for my sidearm. I cant choot people close range with an l96 sniper rifle that i modded for 600 fps, so this will help a bunch.
Hi there....i just discovered the interesting world of airsoft. I have a Jieke Edge P288G "air pistol". Can anybody out there tell me if this is a "reasonable" gun,pls? I've mod my gun according to rambler4's technique and it's slightly more powerful now...just wondering if there's anything else i can do to it. Appreciate some suggestions here,pls. TQ!!!
actually all you need to do to practically double the power is take the small spring ( not the cocking spring) out and stretch it. i did it to my gamo and it works good as. (excuse my english im from new zealand.)
No, you should never do that. It may make it more powerful at first, but it will slowly destroy your spring. It can even half the power of your gun after a month or two.
Brilliant! I think I may do this.
to much time on his hands
Hi lol i just bought my first real bb gun a cyma p - 918 says 200 fps its quite good Im gonna do this nice mod
Nice, the way I see it, you could do this to any springer. or some electrics, for that matter.
I did this to my Crosman Mp5 1 or 2 years ago and it was very much worth it. Along with a few other mods, got the FPS up to 295.
what was the original fps
Not sure ,but I think it was about 180 fps. I do know it shoots farther, straighter and it stings more. Probably closer to 200 fps.
Thanks y'all for looking at my Instructable, and leaving comment. Rolor, what were the other mods. you did to get fps up to 295?

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