Re: New Barrel on M1A Scout ?
Heavy match grade barrels are better. Standard commercial barrels are often pretty good, but may tend to spread groups during rapid fire strings due to heating stress and a light contour.
A quality heavy match barrel will minimize that tendency and shrink groups when combined with the other steps necessary to tune an M1-A... match grade stock, bedding, g/c unitizing, match reamed flash hider, trigger and load tuning.
These other factors are significant with respect to the platform, and perhaps more important to overall accuracy, but will also wring the most potential out of the existing barrel.
TC