I'm considering purchasing an M1A in the near future and am interested in seeing a ballistic comparison between the 18" and 22" bbl.  Anyone know where it might be found.  

Thanks, Theo

PS. Charts are nice. :-)  

Theo --

The bullet's velocity is only marginally slower out of the Bush barrel so trajectory isn't much different.  At longer than engagement ranges -- over 300 meters you'll probably see some differences, but at normal engagement ranges, under 200 meters, the Bush barrel and iron sights work quite well.

An item of interest is the Scout Squad Rifle (with the overly long stock due to a rubber recoil pad, forward sight rail, and muzzle brake) comes with an extra tall front sight on it.  Replacing the brake with a proper M14 flash hider also required use of the tall front sight post.  Replacing that with a Vortex flash supressor required putting on a standard, much lower, M14 sight.  I've no idea why, but keep it in mind if you start to change muzzle devices.

-- Chuck