Calibers and range: Part 2
by B.B. Pelletier
Today, I’ll make the connection between black powder bullets and pellets, so you’ll understand why a .22 caliber pellet travels just as far as a .177.
Did you notice…
…that the modern .30 caliber streamlined bullet in the 1906 cartridge went 200 yards LESS than the fat old .50 caliber black powder bullet at the Yuma test mentioned in yesterday’s posting? Funny thing about that. The .30 caliber bullet is streamlined, but it was not optimized for supersonic flight. It didn’t perform as well as it might have if it had it been the right shape. From that, we know that the 1906 bullet still has high drag, despite being streamlined. Remember that.
Did you ALSO notice…
…that the 675-grain .50 caliber black powder bullet (and by that term I mean that the bullet was propelled by black powder and not by smokeless powder) left the muzzle at a speed just over the speed of sound? Very soon after leaving the muzzle, certainly within the first 50 yards, it became subsonic. That bullet was very poorly streamlined for supersonic travel, so it had extremely high drag until it went subsonic again, then the drag subsided considerably. And, after it dropped below the transsonic region at something under 1,000 f.p.s. (REMEMBER THAT VELOCITY!), it lost even more drag and went into a smooth flight. From that point on, its speed dropped slowly because the heavy bullet resisted the loss better than a lighter bullet (like the 1906 .30 cal. bullet) would.
Here comes the tie-in!
Pellets are very much like black powder bullets, in that they also have high drag caused by their hollow skirts and wasp waists. These two things keep pellets on track as they fly, which is what makes them so accurate…but, they also slow them down more rapidly. So, a pellet acts very much like a huge black powder bullet in that it really likes velocities under 1,000 f.p.s. (did you remember?).
When a pellet leaves the muzzle at velocities above 1,000 f.p.s., it slows down more rapidly than the same pellet going out at 950 f.p.s. When a pellet leaves the muzzle at supersonic velocities, it loses speed so fast that it is subsonic within just a few yards. All the hype about pellets going 1,250 f.p.s is a load of dirty diapers! In fact, pellets that go out at 1,000 f.p.s. do so for only a few FEET, then they drop back from the transsonic range into the subsonic range and cruise smoothly once more.
An AirForce Condor shoots a .22 caliber Crosman Premier at 1,250 f.p.s. That pellet travels downrange no farther than the same pellet leaving the muzzle of an AirForce Talon that poops it out at 900 f.p.s.! All that extra raw power is an advantage only for the first 75 yards, or so. Of course, 75 yards is near the end of the range for hunting with smallbore airguns, which is why the Condor is so popular. Both guns have a nearly identical maximum range (muzzle elevated 30 degrees to the horizon) of about 500 yards. Ain’t life wonderful? That’s called having your cake and eating it, too. Of course, what you can and should do with a Condor is shoot a heavier pellet to slow down the velocity down to the subsonic region, then you will get improved accuracy, not much more pellet drop and a more powerful shot.
Conclusion – part 2
There is no way that a 7.9-grain 1,000-f.p.s., .177 caliber pellet will shoot any farther than a 14.3-grain, 800-f.p.s., .22 caliber pellet. If you don’t understand this, please reread both postings carefully. What the .177 gives you is a flatter trajectory out to about 50 yards. You have to aim higher to hit with the slower pellet. After that, both pellets fall at about the same rate. Since the .22 pellet has already fallen farther than the .177, it will always be lower until the end of its flight. If both muzzles are elevated 30 degrees above the horizon, both pellets will hit the ground at approximately the same place.
I have wanted to make this argument for several years, and the thoughts suddenly came together in my mind last week. Now, you may understand when I caution against shooting at high velocity because it destroys accuracy. Just a little slower puts you back on target, plus it doesn’t really penalize you if you know where to aim.