View Full Version : Need upgrade help

09-08-2003, 10:32 PM
Hey, I have a M4a1 which i ordered about 6 months ago. I ordered a $90 upgrade which upgraded the gun to 400fps and added a unidirection piston head, metal bushings, systema flat gear set. But I recently chronoed the gun for the first time and it was only shooting 330 fps. I want to upgrade my gun to 400fps for OP:SD so basically im asking what type of spring should I get? Is a PDI 120% good? Also is 120% 400fps? Is there any other item I need like bushings? On the upgrade it says that metal bushings were added but Ive never checked so how do I know lol. Anyways do you guys think Id be okay with just ordering the spring or is there other stuff I need also? Thanks.

09-08-2003, 10:35 PM
m120 or a PDI 170

09-08-2003, 10:51 PM
This is what uncompany told me when I asked them about it.

"Dear Sir,

Thanks for your reply, the HurricanE hop up is one reason to make the
weak, as the quality of the hop up is not good. We will suggest you to
the Systema hop up.

Also, spring becoming weaker is another reason as every spring have the
chance that weaker after certain usage.

If there is anything that we can help you with, let us know.

Thank you very much and look forward to your reply.

UN Company"

10-04-2003, 10:52 AM
Well I found out why eXe's gun was only shooting 330. We took it apart and found that UN Company had cut two notches in the piston head, which was causing air to bleed byt the o-ring. They charged him 90 bucks to make it shoot under 330 fps. Makes you wonder what kind of business they are running.

10-04-2003, 01:11 PM
Whats a unidirection piston head?