Images of both the G1 and G7 standard projectiles can be found on the internet. However, the G1 standard is a poor representation of a modern low-drag projectile and in the 1940s the G7 standard came along, representing a modern, boat-tail US artillery shell. They carefully measured the drag of this projectile and also measured the TOF and retained velocity versus distance. The initial standard projectile, the G1 projectile, was of a German artillery projectile. This would allow reasonably accurate retained velocity and TOF calculations. It was an extremely tedious, expensive, and time-consuming effort to get the velocity and drag profile for just one projectile, let alone hundreds of different types.īut the ballisticians of this era figured out that by using a simple ratio, Ballistic Coefficient (BC), they could determine a reasonably good approximation of the drag of any projectile by comparing it to a standard projectile drag, as determined above. The velocity data would then be used to calculate the drag between each interval. The only way to define the drag on a projectile is to use the chronograph to measure the projectile’s retained velocity at various intervals down range. Imagine the challenges facing a ballistician back in the late 1800s: There are no computers, no radar and, at best, this person has access to a very crude chronograph. Today, the 6.5 Creedmoor is loaded by numerous ammo maker’s, including Winchester, Nosler, Hornady, and Federal. 260 Remington, a personal favorite, has struggled, though it gamely fights on. Even though this round has an amazing pedigree-designed in the late 1800s, it had a distinguished military career lasting decades, has an unimpeachable reputation on large game, and regularly won gold medals at the Olympics, thanks to its accuracy-it, too, suffered from the 6.5 curse and failed to reach the summit of the mountain. The 6.5×55 Swede, one of the most popular European cartridges for big game, migrated to North America in the late ’50s with the arrival of thousands of surplus Mausers. ![]() is a hot round with impressive ballistics, but it was overshadowed by the 7mm Rem. The 6.5 Remington Magnum never really got out of the starting gate, and the attempts to revive it were complete failures. This is a shame because some damn fine rounds have been crippled by this bias. 264-have never done well with American shooters. Lastly, it it has a bullet diameter of 6.5mm, and despite the widespread adulation of 6.5s beyond North America’s shores, these cartridges-whether called 6.5 or. Anyway, the metric designation was strike two. It’s the ballistic equivalent of the “Royale With Cheese” from Pulp Fiction. We only called it that because our European allies couldn’t figure out what a. But that Commie round is too crude to be considered part of the pantheon, and only hits the sales it does because of all the cheap military surplus SKS and AK rifles kicking around. The one other popular metric is the 7.62×39. Introduced back in 1962, it has been one of our top 10 hunting cartridges and top 10 centerfire cartridges for many years. ![]() It must be an unwritten rule that American shooters will tolerate one metric cartridge in the pantheon, and the 7mm Rem. Now, there’s one exception to this, and that’s the 7mm Rem. Hate to break it to you, but we tried the whole metric thing back when Gerald Ford and Jimmy Carter were pulling on the oars, and it was as popular as fire ants in a tanning bed.
0 Comments
Leave a Reply. |