FPs barrel proportions.
 

What sized barrel should be used to unleash the maximum range of a 450fps "AEG" using .25G bbs? What is the smallest diameter i can get in a tightbore barrel? is 6.01 safe if high grade BB's are used?

Thank you for your help! :cheers:

6.01 will be to tight and bbs will get lodged in the barrel, resulting in a jam. Also the length of the barrell is determined by what type of mechbox is being used, so a little more information on the gun would be usefull, I think you would find a 6.04 mm tight bore would be best for you.

What do you base this information on? I've been using a 6.01mm tightbore inner barrel in one of my GBBs for over half a year now and haven't had one jam.

Jam occurs on 6.01, 6.02 and 6.03 tight bores if you are using SHITTY brand of BB's.

depending on the gun
and depending on your cylinder.

to avoide barrel suck, you need to match barrel length to cylinder type.
6.01 is ok, but 6.03 will do fine also. keeping in mind, a stock barrel is 6.08mm.


see
http://www.airsoftcanada.com/showthr...ht=barrel+suck
http://www.airsoftcanada.com/showthr...ht=barrel+suck

Just built upon your comment.

m16a2 Tm is the gun up for modding.

just add a M16A2 tightbore, since its a very long gun as it stands...you dont need to go any longer(you could, but the improvments wont really be noticable)

I also want to have wo barrels for my P90 Tr one short one and one long ak47 tightbore Will i get good results from the ak tightbore 6.03 mm? Are there better options. P90 TR's Power is 415fps

In addition. I am using 6.01 and 6.03 tightbore. BB jammed on my 6.03 tight bore using crappy bb's and broken a tappet plate because of that but it didnt stop me using a tightbore but instead I use good quality bb's ever since and never get a jam. my two cents.

It's not an optimal solution.

The P90 barrel length requires a shorter (Type-2 / 1/3rd port) cylinder whereas the AK-47 barrel length requires a longer (Type-1 / mini port / no port) cylinder.

Using a short cylinder with a longer barrel could lead to barrel suck and your power won't be optimal.
Using a long cylinder with a shorter barrel is inefficient as well, consistency goes down and some users claim power losses as well. Remember that a spring's optimal power is near the end of its extension.

But it is a doable option if you have two gearboxes as well that you can swap in and out.