I have been using 6.5gr TrailBoss powder behind my standard full velocity 50gr Hornady SP varmint projectile in my L461 Vixen .222 to roughly duplicate .22 Rimfire Magnum ballistics. This is where the hunting is close & I need to minimize noise. I need to buy more projectiles, & am wondering if there is a better projectile for low velocity expansion? Maybe Hornady .22 Hornet 45gr SP? There are many .224 projectile options, though most are intended to hold together & expand at muzzle velocities above 3000fps - whereas my current load is approximately 1700fps. Also, is my 1977 model rifle .224 or actually .223? I have been using the former diameter projectiles with good accuracy, though it was recently suggested to me that some of the Sakos were the latter diameter. Cheers.