1tonne if I understood right you have 550mm inner barrel in your g-spec? I was reading you advanced vsr guide, really good article, it will help me alot when my bar 10 pro version arrives.
I don't now. That would have been some years back. I now have a 470mm long inner barrel which is good for 0.4gm bb's.
You need to choose your inner barrel according to the bb weight you are going to use.
This is from my VSR10 guide:
"
Here is a rough guideline as to which bb and barrel to use to get the most efficiency from your cylinder.
So chrono your gun and work out the FPS. Then look at the chart and work out the weight bb you need for your FPS. (You can always use a slightly heavier bb and the energy/backspin of the gun should still be able to carry it)
330-370fps = 0.23-0.28gm
370-420fps = 0.28gm-0.30gm
420-450fps = 0.30gm-0.32gm
450-500fps = 0.32gm-0.36gm
500-540fps = 0.36gm-0.4gm
540fps upwards = 0.40gm-0.45gm
(These FPS/BB weights can be used with any gun setup. So if your pistol is firing at a ridiculous 540fps then use a 0.40gm as long as there is enough air in the cylinder to push it out the barrel)
(Also note that often you can increase the weight of your bb if you use a longer nub on you hopup rubber. The longer nub will help to create more backspin and this will help carry the bb further. This is why R-hop is so effective)
Now to get the best efficiency from your
VSR10 cylinder with this bb weight you need to get the right length barrel
Note: I use 6.03mm barrels and information in purple is for the tech head type people and so if you are not into tech stuff and are just starting out please ignore the purple text
Action Army Cylinder Dimensions
Piston Travel Length: 90.2mm
Cylinder diameter: 22.5mm
Compression Volume: 35864 mm^3
So see the chart below:
0.3gm bb use a 554mm barrel (15821 mm^3) = 2.26:1
0.32gm bb use a 530mm barrel (15136 mm^3) = 2.36:1
0.36gm bb use a 500mm barrel (14279 mm^3) = 2.51:1
0.4gm bb use a 470mm barrel (13422 mm^3) = 2.67:1
0.43gm bb use a 430mm barrel (12279 mm^3) = 2.92:1
0.45gm bb use a 400mm Barrel (11423 mm^3) = 3.13:1"
