Airsoft Canada - View Single Post - Inner Barrel Length and FPS Rule of Thumb?

AnthonyG · February 11th, 2017, 13:14

So, with all else being equal, a longer inner barrel yields a higher FPS than a shorter inner barrel of the same make and model. This is basic physics: the longer the bb is in the barrel, the more time it has to accelerate (assuming the correct cylinder volume), thus the higher the FPS.

My question is, has anyone figured out a general rule of thumb for estimating change in FPS per length of barrel? ie) Every 25mm of additional length yields an increase of 5fps, for a 6.01 barrel etc...

Right now I use two barrel assemblies for my primary to switch it from indoor legal (370fps) to outdoor legal (395fps), but both of my barrels are different makes and have different bores, and I don't have access to enough barrels of the same make to actually perform these tests.

February 11th, 2017, 13:14	#1
AnthonyG LUser Title Trader rating Join Date: Aug 2014 Location: Pickering/Toronto	Inner Barrel Length and FPS Rule of Thumb? So, with all else being equal, a longer inner barrel yields a higher FPS than a shorter inner barrel of the same make and model. This is basic physics: the longer the bb is in the barrel, the more time it has to accelerate (assuming the correct cylinder volume), thus the higher the FPS. My question is, has anyone figured out a general rule of thumb for estimating change in FPS per length of barrel? ie) Every 25mm of additional length yields an increase of 5fps, for a 6.01 barrel etc... Right now I use two barrel assemblies for my primary to switch it from indoor legal (370fps) to outdoor legal (395fps), but both of my barrels are different makes and have different bores, and I don't have access to enough barrels of the same make to actually perform these tests. __________________ *Busy signing for his packages*