I had some parts come in today, another tightbore (this time a 6.02 500mm barrel), another guarder steel hopup and an assortment of hopup buckings for the guarder chamber. I assembled the two barrels with the chambers and new buckings (same brand), and then using the same lower with different uppers but same bolt, I tested fps again.
The 500mm 6.02 barrel is barely coming in above 360fps, while the standard length 6.01 barrel is chronoing over the 470 mark. Is that .01mm difference causing the fps variance? Seems like a small enough difference not to matter. I was expecting the 500mm barrel to have higher fps, and I would not be as puzzled if they were even close to the same fps, but the +100fps difference has me scratching my head.
The only real difference (besides barrel length) is the fact that the upper with the 500mm barrel has not been cleaned, seasoned and lubed with frog lube.
Edited by SuperFly, 05 September 2012 - 09:53 PM.