308 Winchesters beat the muzzle velocity of the. Muzzle velocities of 2,150 to 2,175 fps were observed, lowering the energy values closer to the 4,000 ft-lb mark. 416 Rigby was put through a modern chronograph, the results were eye-opening.
The problem is, a ballistic pendulum and a long test barrel were used to obtain those “defining figures,” and when original ammunition for the. This has been a benchmark for comparing newly developed cartridges and, if a cartridge doesn’t develop those velocity and energy figures, it’s generally been frowned upon. 416 Rigby load used a 410-grain bullet at 2,350 fps for 5,000 ft-lb of muzzle energy. Keeping a record of the velocities of your handloads will help you in years to come.įor example, the original. The same can be said for a reloading manual. Is that gospel? Certainly not, because the manufacturer has no idea what type of firearm you’ll be firing that ammunition from, its barrel length or any other parameter. Taking a look at any box of ammunition, you’ll see a certain muzzle velocity listed. Reaching a target muzzle velocity figure in your handloads can be equally challenging. I’ve seen this phenomenon with the longer, heavier-for-caliber bullets, such as the Nosler AccuBond, Hornady ELD-X and ELD Match, along with other similar bullets. I suppose the bullet, like a spinning top, needs some time to obtain the perfect stability. However, it shows a definite preference for flat-based bullets, and I suspect the bore might be a bit “loose.” In spite of a 25-inch barrel, the velocities for this rifle are lower than expected across the board, further confirming my suspicion.Īlso, consider this: I’ve seen more than one of the modern, high-BC bullets need time to settle down, giving better groups at 300 yards than at 100 yards.
The individuality of your barrel most definitely comes into play where group size is concerned, and there are so many variations that it sometimes seems no two are alike.įor example, my 6.5-284 Norma is a Savage rifle-from its custom shop-and it’s most definitely one of the most accurate rifles I own, giving 1/3 to ½ MOA groups out to 500 yards. I’m not suggesting you call off the pursuit of accuracy in your handloads once you hit the 2 MOA mark, but I am saying that not every rifle is capable of ½ MOA performance. Carefully handloaded 6.5-284 Norma ammunition, which is wonderfully accurate, is slightly below expectations in the velocity department. We’re seeing sub-MOA guarantees on more models each year-to the point that a rifle that delivers a 2-inch group at 100 yards causes the shooter to make a face as if they’ve just taken a mouthful of sour milk. Inexpensive rifles are delivering groups that would have surely turned the heads of our grandfathers. Of course, many hunters were using iron-sighted lever-action carbines, and minute-of-pie-plate at 100 paces was “good enough.”īut, I feel modern rifles are also the best available. When I was a younger man, anyone who had a 1 MOA rifle was talked about in reverent whispers-as if they owned some mythical weapon blessed by divinity. Why does this happen? And why, when you see a target from a friend or acquaintance produce a target from a particular “recipe,” doesn’t your rifle produce a similar group?įirstly, modern rifles are showing more-consistent results than we’ve ever seen. It can be maddening, especially when you’ve chosen a particular cartridge for the velocity potential and you see numbers that are, well, disappointing. You’ll sometimes see significant differences in the maximum charge weight, as well as the velocity for that weight charge.
And, once we see a muzzle velocity figure published for a particular cartridge, there’s little others can do to drive that benchmark from the mind.Ĭomparing the data in several reloading manuals, you’ll find some rather wide variations in muzzle velocity figures, even for the same load. Exactly what factors are you dealing with in the chase for each?Īccuracy in a rifle-even though “precision” is the word we actually should be using-is something every reloader is after. Desired muzzle velocity and downrange accuracy prove elusive goals off the reloading bench.
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