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flat pistons/valves?

Started by woody67, February 08, 2011, 09:37:35 PM

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woody67

What do flat pistons and valves do for a 1377? Do they give the gun more power?

I'm really looking to turn the power up on my 1377, possibly convert it to a .22 if i can keep high FPS and FPE.

Also, will a longer barrel increase fps? I can't see how it will, but I have heard that it does.

THanks...

jj

Crosshairs

[youtube]https://www.youtube.com/watch?v=uIIG-aa3VrM#]1377 piston and valve mods[/url]       This might help !
                                                                                 Mike
Treat people the way you want to be treated, Life will be so much better !!!

Nate

a longer barrel will absolutly increase FPS. i dont know much about flat top pistons/valves though

airguns100

Mike @ 2:35 the term your looking for is it gives a "cam roll over" effect.


Modifying the valve makes a hugh difference in conjunction with a brass FTP. The piston should be made out of metal imo.
AC customs valve mods and a AC brass piston and better orings will increase FPS

Adding the a longer barrel will literally floor your FPS numbers through the roof!



The OG gangster of the "bling"

quickster47 †

Quote from: airguns100 on February 08, 2011, 10:48:13 PM
Adding the a longer barrel will literally floor your FPS numbers through the roof!

Shouldn't that be "Adding the a longer barrel will literally SHOOT your FPS numbers through the roof!"

Carl

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

Crosshairs

I gained almost 100 fps with a 24" barrel.
                      Mike
Treat people the way you want to be treated, Life will be so much better !!!

woody67

I would not have expected that, but I guess it makes sense after thinking about it. Having a 24" barrel makes you not really have a pistol. What does the length, in most cases, of a barrel have to exceed in order for it to negatively effect FPS?

I'd like to keep mine as close to a pistol/handgun-ish state as possible...although I know it will have be be extended. What is the shortest length barrel that I can use and still keep the fps as high as possible? ---(flat top piston/valve,steel breech, all that stuff included)

quickster47 †

Quote from: woody67 on February 09, 2011, 05:19:11 AM
I would not have expected that, but I guess it makes sense after thinking about it. Having a 24" barrel makes you not really have a pistol. What does the length, in most cases, of a barrel have to exceed in order for it to negatively effect FPS?

I'd like to keep mine as close to a pistol/handgun-ish state as possible...although I know it will have be be extended. What is the shortest length barrel that I can use and still keep the fps as high as possible? ---(flat top piston/valve,steel breech, all that stuff included)

Part of that depends on whether you are using CO2 or HPA.

I really think what you are asking is more of a personal thing than anything else.  Sure there are some basic guidelines but each person usually has some requirements that dictates where they go in modifying their gun.  A 14" barrel is going to be pretty much the max for a pistol, and it then sort of becomes a 'Buntline' or 'Joker' special.  10" or 12" is more realistic for a pistol.

Carl




I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

woody67

Quote from: Mike on February 08, 2011, 10:09:30 PM
[youtube]https://www.youtube.com/watch?v=uIIG-aa3VrM#]1377 piston and valve mods[/url]       This might help !
                                                                                 Mike

Great video...that was very helpful. I am going to order my valve/piston from AC. I'm also looking for a steel breech where I can have the bolt on the left side of the gun. I think I saw one, I just can't remember where.

Crosshairs

Im glad it helped you,im no pro but i try to help some way.
                  Mike
Treat people the way you want to be treated, Life will be so much better !!!

Plasticman

I have found that 18 inches give the same fps as 24 and 14 inches is not a whole lot slower 10 to15 fps is all. I find the 18 inch barrel to be a bit of a pain to pack around and don't really like more than 12 inch barrel on a pistol. Go with 14 in 177 cal. and you will get the best fps and accuacy.

airguns100

Quote from: Plasticman on February 09, 2011, 07:36:46 PM
I have found that 18 inches give the same fps as 24 and 14 inches is not a whole lot slower 10 to15 fps is all.

Carl.

This is something i hear on the yellow and the green all the time. My point proven  ;D
The OG gangster of the "bling"

airguns100

Quote from: quickster47 on February 08, 2011, 10:51:02 PM
"Adding the a longer barrel will literally SHOOT your FPS numbers through the roof!"

Carl


i was thinking about using the word "shoot" but i thought it might give some people bad idea's  ;D :P
The OG gangster of the "bling"

ray1377

I gained almost 56fps with the flat top piston.
And another 100fps with a 24 inch barrel.
It was well worth the money in my opinion.
Thanks
Ray
Ray Thomas


Master of the 1000 inch shot.

SaiCo

Quote from: woody67 on February 08, 2011, 09:37:35 PM
What do flat pistons and valves do for a 1377? Do they give the gun more power?
Not more power per se. But improves efficiency, when the OEM cup seal on the piston meets the valve, there is "dead space" or air that is not pushed into the valve. Some just reface the cone part of the valve, but I guess it's easier to just go flat. Flat top pistons need more lubrication from what I've read.
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