Re: 300WM shooters.
Thoughts by some guy named Mike Rescigno on the topic... owns a little hole-in-the-wall outfit called Tac Ops:
"An 18- to 20-inch barrel may be fine for a caliber like the .308 Win., but what about calibers such as the .300 Winchester Magnum (7.62x66B)? Many agencies are opting for this cartridge as a result of its long range ballistics. The .308 Win. has a maximum effective range of about 800 yards. While this is certainly more than enough for most law enforcement scenarios (law enforcement snipers rarely have to engage targets at more than 100 yards), the .300 Win. Mag. does increase the maximum effective range by an additional this comes with the price of additional recoil.
Many agencies purchasing a .300 Win. Mag. will primarily be employing the rifle in an urban environment. The common reason for opting for the .300 Win. Mag. that it extends the capabilities of the rifle to longer ranges than the .308 Winchester is capable in those rare situations where longer range capability is necessary. This leads to an obvious question -- will going to a shorter barrel for added maneuverability in the urban environment adversely affect long range performance of a rifle in this caliber?
To find the answers, Tac Ops took a 26-inch barreled .300 Win. Mag. and chopped the barrel down in one-inch increments as they previously did with the .308 Winchester. Ten rounds of Federal Match 190-grain BTHP Gold Medal were fired from each increment. No velocity was lost from 26 inches to 22 inches. Velocity loss started to occur only after they went below 22 inches.
As a result of their tests, Tac Ops decided not to go below 22 inches on their .300 Win. Mag. tactical precision rifle, the Alpha 66. According to Mike Rescigno, President of Tac Ops, the 22-inch barrel is ideal for the tactical shooters that are going to use the 190-grain Federal Match ammo. There isn't any loss of performance by going to the 22-inch barrel and this round. The Alpha 66 still provides 1/4-MOA or better accuracy.
For heavier bullets or hotter loads with slower burning powders, Rescigno recommends a 24- to 26-inch barrel. The longer barrel length is necessary for complete powder combustion with these loads. Rescigno adds that he has a 24-inch barrel on his personal .300 Win. Mag. just in case he wants "to shoot the heavier 220-grain bullets with a lot of powder."
FWIW
John