STEADFAST .300 BLK 240gr HPBT SMK Subsonic is constructed utilizing a Sierra Matchking hollow point boat tail projectile loaded in new brass casings.

Cycles most factory semi-auto rifles.

Velocity: 1020 fps in a 16 inch bbl with 1:8 twist

Recommended for barrels with a twist rate of 1:8 or faster – e.g., 1:8, 1:7, 1:6, 1:5.
Slower twist rates (e.g., 1:9, 1:10) may under-stabilize the bullet and inhibit accuracy.