On May 2, 1878, in Minneapolis, the Washburn “A” Flour Mill exploded, killing 14 workers instantly, leveling a mill capable of churning out boxcars of flour every day, and gutting five nearby mills.
The cause of the Washburn “A” tragedy was a mystery at the time. Milled flour isn’t particularly flammable, so this idea was dismissed initially for other explanations like gaseous decomposition in the nearby Mississippi river. John A. Christian, the mill’s manager, proposed flour dust in the air burned rapidly, once ignited. Christian was right.
The principle that caused the devastation is the same concept that prompts us to warn about leaving lots of space in a case. Light loads in big cases have the potential to kaboom, rather than burn at a predictable rate. There are other ways to cause a cartridge kaboom, and it’s up to you to implement safe inspection and reloading practices.
Always look at the powder dispensed into your cartridges under strong light.
The left has 4 grains. The right has 8 grains. Make sure your lighting and
angle allow you to differentiate.
To avoid the dreaded kaboom, be cognizant of any anomaly in the shooting behavior of your gun. Anomalies include: a gun that exhibits no recoil, unusual amounts of smoke or flame, or a change in the operation of the gun. Any time an anomaly occurs, stop and figure out the cause. Of course, start checking for anomalies before shooting by inspecting brass for discoloration, cracks or bulges — even in loaded cartridges.
“Out of battery” means the action/chamber of the gun is not completely closed, and the gun managed to fire. Although brass is pretty strong stuff, it is both the brass and the chamber of the gun that contain the pressure of the fired cartridge. The chamber shouldn’t open until the pressure has lowered to safe levels, and a partially opened chamber usually causes brass rupture. Out-of-battery firing is usually a mechanical failure.
Lindsey runs a Hornady Lock-N-Load Ammo Plant Progressive Press and uses
Hornady Custom Grade full-length sizing dies to minimize case bulge issues.
“GLOCK bulge” is not limited to GLOCKs. It occurs when a high-pressure load is fired in a partially supported chamber — common in earlier GLOCK models. There’s nothing wrong or unsafe about a partially supported chamber. They were designed to feed reliably, and cartridges that meet SAAMI specs will work in them just fine. The problem is the brass expands in this area, which causes a “guppy belly” on the brass. This is especially common in .40 S&W because it is thinner near the case web than a 9mm, and the pressures for these cartridges are comparable.
Initially, I had a real problem with GLOCK Bulge, because I shoot an old GLOCK, plus I pick up range brass. I wisely got Hornady New Dimension Custom Grade dies and run them all the way until the base of the die kisses the shell plate. You can also use a Lee APP Bulge Buster Kit. It pushes the entire brass through a carbide sizing die.
This barrel bulge is from defective ammo. The shooter fired the
squib load, which lodged in the barrel.
A squib load occurs when there is insufficient powder, or no powder, to propel the bullet all the way out of the barrel. In semi-automatic firearms, a squib load will normally fail to cycle, and the shooter is well aware something is wrong.
One day I was on the range and I was shooting side-by-side with my friend, another firearm instructor. My gun gave a slight pop and reduced recoil. I didn’t think anything of it. I went “Tap, Rack, Target” and my shooting buddy yelled, “STOP!” I was working out of force of habit. Fortunately, part of the habit is to perform immediate action (Tap, Rack, Target), but assess before squeezing the trigger. There was a bullet lodged in my barrel. If I had fired, the result would have been a serious kaboom. Always assess before squeezing the trigger.
A double charge is when more than one measurement of powder is dispensed into a given cartridge. Squib loads and double charges are prevented by using consistent reloading techniques. If you’re using a single stage press, eyeball your cases with powder in them under a strong light. For progressive setups, attach a bright light under the press that allows in-line powder checking, or use a Dillon Powder Check System.
I have done this, and I admit it. I have loaded a 9mm cartridge into a .40 S&W gun. In my defense, the cartridge had fallen into a box of rounds. Fortunately, nothing came of it. It could be, and has been, disastrous for those who have forced a 10mm into a 40 S&W chamber, or similar.
Most kabooms are preventable. The best prevention is to establish consistent reloading habits and adhere to them.
