New 300 WSM SUBSONIC ammo! 180 grain Sierra SP (soft point) flat base Pro Hunter bullet, New Winchester 300 WSM brass, Fed 210M primer. Ammo is loaded single stage by hand and the powder weighed out individually. This bullet will stabilize in a 1:12″ twist or faster (1:11″ and 1:10″).
1050 fps in 26″ barrel (suppressed).
50 rounds per order!!
Why use a 180 grain Sierra SP (soft point) flat base, instead of a BTHP or match bullet? When shooting at subsonic speeds, bullet stability becomes a huge factor for the bullet to properly stabilize and for it to shoot well. Bullet length is a major factor in how stable it is out of the muzzle. In a given twist rate (like a 1:10″ barrel twist) and slow subsonic speeds, a shorter, flat base bullet is more stable than a longer BTHP match bullet is. The 180 grain Sierra SP flat base is a much shorter bullet than a similar weight BTHP bullet, like a 175 grain Sierra MatchKing. This allows the 180 grain SP flat base to be more stable and have the potential to be more accurate at subsonic speeds than a BTHP design. BC (ballistic coefficient) is for supersonic flight, and does not matter at subsonic speeds. Having a high BC bullet at subsonic does not benefit the shooter at all. This is why the 180 SP flat base bullets work well as subsonic round!