![]() **For Ruger Redhawk, Blackhawk and Super Blackhawk revolvers only. *Loads proven safe in author's gun, but he has seen pressure signs in others. When you're launching a 300-grain bullet past 1,200 fps, you want to keep the margin available in case of trouble, not use it to generate a few more feet per second. 44 Magnum loads maxing out at 35,000 psi (or 38,000 CUP). All the top-end reloading data with pressure-tested data shows. The pressure can't be increased, for there is no margin left. The only way the newest loads can be used is to extend some of the limits of what Elmer Keith started: more weight out of the case and slower powders. The bullets range from the 270-grain Speer Gold Dot to the Hornady 300-grain XTP and Oregon Trail's 310-grain Trueshot. 44 Magnum," is achieved with even heavier bullets. And yes, Virginia, you must experiment with many different bullets in order to find the one your rifle likes.The newest and even more powerful level, the "third. Accuracy is more important in the long-range game than muzzle velocity or bullet shape. ![]() ![]() I tell all of my long-range shooting customers, shoot the longest, heaviest bullet that your rifle shoots best. Use these tables as a general guideline only. The moral of the story? When you approach the theoretical limit of what a caliber/twist rate combination should stabilize and your bullets are keyholing on the target, increase the muzzle velocity (if you can and still stay safe), switch to a more round-nosed bullet shape, or switch to a slightly lighter/shorter bullet. That bullet is spinning at 3,600 rps of 216,000 rpm. By contrast, take a 22-250 varmint rifle with a 1 in 12″ twist firing a bullet at 3,600 fps. At a muzzle velocity of 2,000 fps, that same bullet will be spinning at 1333.3 rps or 80,000 rpm. At a muzzle velocity of 1,000 feet per second (fps), the bullet is spinning at 666.67 revolutions per second (rps) or 40,000 revolutions per minute (rpm). For example, let’s consider the same 45 caliber rifle with a 1 in 18″ twist rate. That spin rate, in revolutions per second or minute, keeps the base and nose of the bullet traveling in the same direction. ![]() I’ll bet, however, that most shooters don’t realize that velocity and twist rate determine the speed at which a bullet spins. The reloading manuals are full of ballistic tables showing velocity at the muzzle and 100, 200, 300, etc. That is, unless you can keep velocity high.Įvery shooter knows the term velocity. The moral of the story? When you approach theorized limit of what a caliber/twist rate combination should stabilize, stay away from spitzer-shaped bullets. The center of mass is therefore not the middle of the bullet and it will require more spin to keep the nose and base aligned. On the other hand, a spitzer-shaped bullet has most of its weight contained within the base half of the bullet. A round-nosed bullet is more like a cylinder, has its weight very evenly distributed along its entire length and takes less spin to stabilize. Both parameters come into play especially when you approach the limit of what a caliber/twist rate combination should stabilize.Ĭonsider a bullet as a cylinder. The Greenhill Formula does not, however, take into account bullet shape or muzzle velocity. Maximum Length of Bullet Stabilized (inches) Twist> Maximum Weight of Bullet Stabilized (grains) Twist> The following tables are based on the Greenhill Formula. Using them will allow you to estimate the heaviest/longest bullet a gun will stabilize based on the caliber (left-most column) and twist rate in inches (top-most row). For example, a 45 (.457) caliber rifle with a twist rate of 1 in 18″, should be able to stabilize a bullet up to 672 grains or 1.74″ in length. Use the information on the Twist Rate & Stability Tables below to help pick the right bullet …
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