Hey there Lot to Learn, the only way to truly measure the actual speed of your arrow is to shoot several times through a chronograph and then average the results.
With that being said, however, I shoot a Martin Bengal, 60 lb. draw, 29 inch draw, Gold tips with blazer vanes and 100 grain tips. So our set up is very comparable although your bow might have a little more energy (and therefore speed) than mine but that is really debatable. My total arrow weight is 353 grains and my arrow speed is 273 feet per second.
I think your 278 is in the ballpark. I understand you want as much speed as possible but keep in mind that in the past villages have been fed with low poundage longbows and crooked arrows that traveled less than 100 fps. For hunting purposes, it will always come down to a razor sharp broadhead and shot placement. Your current setup is more than enough to keep your freezer stocked and your trophy room full.
Internet Pro Staff Member - Indiana
Glad to talk to all of you, but I'd rather be sitting in a tree stand on a cool morning trying not to move so that the bruiser buck directly below me doesn't figure out that I am watching him!