GUIDE for BARREL LENGTH and BB WEIGHT

[Sprint]

As you'll soon be able to tell i didn't get out to skirmish today!

Instead i rounded up this information into something that should be simple to follow and get decent results without having to do a load of number crunching.

All figures are a guide so if you are between figures just average it out.

The figures in the tables are the result of correlations, basic math and 12 years of playing and testing, trial and error whilst building various guns up with the main goals being consistency and effective range.

I have gone quite far all over the spectrum testing various combinations of BB weight / barrel length / cylinder volume and believe that if you at least start here you're not going to be far of the mark.

I have grouped things in three colours for ease of comparison.

Please note that this is all based on SPRING POWERED SNIPER RIFLES and your usual V2/V3 AEG's & EBB's, not GBB or HPA systems.



CHOOSING BB WEIGHT

The weights shown for relative FPS (give or take 0.05g) have proven to have the flattest trajectory whilst also giving best effective range and decent 'time to target'. NOTE: FPS using 0.20g!

http://forum.zeroin.co.uk/attachment...4&d=1504469879




REQUIRED CYLINDER to BARREL VOLUME RATIO

Relative to the weight of the BB you are using you need a cylinder volume capable of accelerating the BB to maximum potential.
The heavier the BB the slower its acceleration time, so you need more volume to fully accelerate it by the time it leaves the end of the barrel.

http://forum.zeroin.co.uk/attachment...6&d=1504469881




KNOWING YOUR CYLINDER TYPE

If you are serious about getting the best effective range you should at least be running a TYPE 1 cylinder to make the most of heavier BB weights.

http://forum.zeroin.co.uk/attachment...5&d=1504469880




CALCULATED BARREL LENGTH

Generally speaking if you use a shorter barrel than listed you end up with a louder muzzle report and marginal performance drop, if you go longer you actually hurt performance and moreover consistency, i believe this is due to the BB touching the barrel because there is not enough air left to 'cushion' the BB from touching the barrel.

All barrels are calculated on the inner diameter of 6.03, time and time again this size has proven to give consistent results wether in a 500FPS sniper or 330FPS AEG.

http://forum.zeroin.co.uk/attachment...3&d=1504469878




I know there are loads of other variables that may get you closer or farther from perfection but i think these are the key points, i hope this will be useful, any constructive criticism will be appreciated :D

Also MODS hopefully this is in the correct section

[Hangtight]

Re: GUIDE for BARREL LENGTH and BB WEIGHT

Excellent correlation between your numbers and my own experience.
Perhaps we could exhance this a little with an explanation of how to calculate the required volume and cut the port in your own cylinder for your choice of barrel length and BB weight.