The 14.5 retains the 2700 fps necesary for 55gr bullets to fragment out to 100 yds half of what you get from a 20"16"keeps the 2700 fps range to 130 to 150 max considering since WW2 95% of infantry engagements take place at 100yds and under go with the 14.5 with permanent phantom if its a preban or get it crowned with a fake suppressor from kurts kustom firearms to have the look,14.5 is more than enough for real world fighting range if you are in wide open streches of space go with a .308 where your more likely to take a longer shot and see farther than 100 yds.The 14.5 retains the same accuracy as the 20"barrel out to 350 yds so even though the ball ammo wont fragment at that range you can use a good hollow point up to 77gr to get the job done thats why the rifle is so versatile use for CQB,compact rifle or medium range precision shooting,range employed will dictate bullet weight used and bullet type.