I am not too big into long range shooting but I have a spare 11" upper, an elite iron delta can, and a SS 3.5x14 scope in my safe doing nothing.  I was thinking about putting these 3 together and trying it out to 500 yards.  Where I live 500 yards is about the farthest I can go.  I know the shorter barrel will cost me velocity but what will I loose in accuracy?  I don't hand load, will be using mostly 62 gr factory stuff.  Maybe use the setup for coyotes every now and then.  Am i wasting my time with this?  The upper is a factory BCM with alpha rail,
thanks

Short barrels can be very accurate. They are stiffer for a given diameter than a longer barrel.

Barrel length and accuracy aren't tied together. Ammunition will be your deciding factor on accuracy, and the heavier you go, the better chance you'll have of accuracy at that range, up to a point. Even with a 16" and 55gr loads, its' really running out of steam at 500yds. But step up to 69gr smk and you'll notice a difference on steel and it'll handle wind a lot better.

yup only thing longer barrels give is velocity thats it they are no more accurate unless you go so short the bullet has stability issues. iv seen videos of a daniel defense mk18 making shots at 400 yard targets very consistently.