Pellet penetration: they can go deeper than you think!
by B.B. Pelletier
I received a question from Michael N. on Friday that I thought needed to be shared with everyone. It concerns how far a pellet can penetrate.
Since my backstop has proven useless against my slingshot, I’m thinking of buying a Gamo 850 carbine to try to punch holes through that phonebook I mentioned earlier. Will it punch through with Crosman Super Points, or maybe Premier Ultra Magnums?
This comment was preceded by a confusing string of comments, but it appeared to me that Michael wants to use a phone book as a backstop for his pellet gun. If that’s the case, and for everybody else out there who has similar thoughts – this post is a report on penetration.
You might think the answer to Michael’s question is, “Which phonebook are you shooting at?” but it isn’t. All the phone books for New York City aren’t sufficient to stop pellets! Allow me to explain.
Some embarrassing history
During World War II, the U.S. mobilized all industries to support the war effort. Companies such as Daisy and Crosman made parts for the war, as did many other less likely companies. The M1 Carbine program was one of the most ambitious production programs of the war. They went from not having a carbine in mind in 1940 to producing more than 6 million guns by the end of 1944. To do this in an era of machines run by humans instead of computers, the government had to organize a huge system of production that involved 9 or 10 prime contractors (depending on how you count the one that never delivered) and dozens of subcontractors. Winchester was a maker, but so were IBM, Underwood Typewriter and Rockola – a jukebox manufacturer.
While these companies knew about mass-production (some more than others), some of them were not up on basic firearm safety or of the performance characteristics of firearms. This was compounded by the fact that the M1 Carbine shoots what is essentially a pistol round, and is therefore not afforded the respect that it should be by unknowing workers.
M1 Carbine round in the center is basically a pistol bullet, running hot. It’s closer in killing power to the .45 ACP pistol round to the left than to the WWII standard .30 caliber U.S. rifle cartridge (.30/06) on the right.
One of the prime contractors for the carbine was the Thermoplastics Division of The Standard Products Company. This company had primarily made parts for automobiles before the war. They converted their plant to build the carbine, and had to construct an indoor range for proofing, function testing and sight adjustment. The backstop was ten FEET of damp sand, backed by a 10″ thick concrete wall. One evening while several office personnel were blasting away on this range for fun, a night watchman outside the building saw bullets blowing through the wall and ricocheting off the perimeter fence! He saw light streaming through many holes in the wall!
Fortunately, he was able to stop the shooting. The company had to build a proper range with real safety features before resuming testing. If you’d been asked if a 110-grain .30 caliber bullet with 1960 f.p.s. muzzle velocity could go through 10 FEET of wet sand and 10″ of concrete after that, would you have said yes?
One bullet can’t. Ten bullets can’t. But when bullet after bullet is fired at the same place, time after time, eventually they chew their way through. And eventually doesn’t take as long as you think.
Respect is what I want to address today. Respect for airguns. Just because they are weak compared to firearms, always remember that the M1 Carbine round is also very weak, and look what it did. Twelve years ago, while shooting in my basement, I missed the big steel bullet trap that caught all my pellets. One pellet from a .25 caliber Webley Patriot hit a cinderblock in the foundation wall and chipped out a 3″ spall. That would have been bad enough, but when I examined the spot more closely I discovered that the pellet had cracked the entire side of the cinderblock I was able to see! One pellet!
I suppose it was my bad luck that I wasn’t shooting a Diana model 27 when this happened, but also my good luck I wasn’t shooting a Career 707 loaded with 28-grain Eun Jin pellets! I never thought I would ever miss the huge bullet trap, when most of my guns shoot quarter-inch groups at this distance. But a touch of the trigger at an inopportune time while shooting at an outside bull on a 10-bull target brought all the circumstances into alignment at the critical moment.
Think I learned from that? NO! I put a half-inch 3’x3′ plywood board on a slant behind the trap and continued shooting. Two years later, after more than 50,000 more shots had been fired, I had occasion to look behind the plywood board. There were six more spalls – all smaller than the first, due to the backer board, but against the light yellow wall they looked like the backdrop to the St. Valentine’s Day Massacre! Six misses out of 50,000 shots. Not a bad record, if you don’t own the house, but I did.
Newspapers, carpets, phone books and boards are all just temporary backstops for pellets. If 100 shots land in the same place, they will do a lot of damage. Heck, I used to shoot more than that in just one session. But a real steel bullet trap, backed by 1.5″ of plywood about 3’x3 ‘ is a good start to a safe 10-meter range. My own steel trap was made by Outers many years ago and has absorbed over a quarter million rounds by now. It has stopped guns up to 120 foot-pounds and still looks untouched, except for paint loss. Pyramyd Air sells the equivalent trap they call the Heavy Duty Metal Trap.
Airguns are a great extension to the shooting sports. They have less power than firearms, for the most part, and are easier to use indoors. We have to remember the basics of shooting safety all the time, even with lowly airguns, because weak or not, they will get away from you if you don’t pay attention.