Jump to content

to add your 300x250 banner, pay ad zone 5
Airsoft Atlanta is your source for quality airsoft guns and rifle parts
to add your Text Link here, pay ad zone 3

AirsoftAtlanta.com AirsoftNMore.com Airsplat.com AirsoftRC.com
Vote for us to add your 180x30 banner here, pay ad zone 2

If you appreciate this website, please ASF Donation or Check Out the ASF Store. If you can not help us financially,
then at least help us by telling a friend: Share us on your favorite social networking website Bookmark and Share
Sign in to follow this  
Dr. Frankenstein

Low FPS issue.

Recommended Posts

Howdy,

My issue is low FPS on a new unfielded ICS CXP M4, Normal FPS was supposed to be 360-390. But here is what I did, I turned the CXP into an SPR and added a madbull 509mm 6.01 tbb, and thats it for now. I took it to the shop to chrono and then field test, 298 FPS and a 72 pace range which translates to roughly 150ft. Im hoping someone has some insight into why the FPS is so low and what I can do to fix it.

 

Thanks!

Share this post


Link to post
Share on other sites

how long was the original inner barrel length? it could be that there isn't enough air in the cylinder to get the BB all the way out the barrel under pressure.

what happens is, the BB gets like 3/4 of the way down the barrel but runs out of air pushing it forward. it starts to create a vacuum behind it because theres no air in the gap behind the BB that keeps expanding as the BB makes out that last 1/4 section. Its like the same idea as dipping a straw in a drink and holding your finger on the end of the straw to trap the liquid from falling out as you raise the straw from the glass.

The solution is to put the old barrel back in or get a bore-up/unported cylinder. its also possible that you messed up the install and you have an air leak.

Share this post


Link to post
Share on other sites

No doubt then your original cylinder is probably ported to only have enough air for that short barrel. you want a cylinder with no port for sure and almost 100% sure you want a bore up cylinder. That means you need a bore up cylinder head and piston head too btw.

I'm fairly sure that they do. you might want to look for ICS brand parts. their stock and aftermarket parts aren't bad at all and sure to fit into their own model.

https://www.evike.com/products/26060/

https://www.evike.com/products/26053/

https://www.evike.com/products/28027/

Edited by Hellion_Blade

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

×
×
  • Create New...