Amos is right, Skladfin usually doesn't know what he's talking about anyway
barrel length has absolutely NOTHING to do with range, OR ACCURACY
It's meaningless. It has no bearing what so ever.
What matters is COMPRESSION, and QUALITY.
You can have a 650mm 6.08 G&P barrel in a gun with a full upgraded prometheus mechbox, and I guarantee you it won't shoot as nice as the same gun with a 247mm prometheus 6.03 barrel.
Case and point, my stock HFC beretta, with a barrel shorter than 160mm, could outrange, and was more accurate, than a stock TM VSR-10. It shot as well as some well upgraded AEG's
My TM VSR-10 has a 430mm barrel, it had the exact same upgrades as Amos' VSR-10 at the time, except he had a 650mm barrel and an extra 70fps on me. Guess what? We got the same accuracy, and he got about another 15 feet of range on me with that extra 70fps.
Barrel length means nothing in spring guns and AEG's.
Your BB never actually hits the side of the barrel, the compressive forces keep your BB centered down the length of the barrel. So the longer your barrel is, the more air you need to keep it centered, and the longer you NEED to keep it centered, the greater chance of something going wrong with the air current or with barrel defects or with dirt in the barrel.