Adding Nuance To The FBI Gel Test Standards

The FBI gel test standards are generally held to be the benchmark by which ammunition is judged, both for law enforcement and – because the trend has always been for civilians to carry what cops carry – for the armed public. 

Instead of just rehashing the test protocol, let’s talk about the why behind them, how that applies to you…and why it may not apply.

Where Did The FBI Gel Test Come From? 

The FBI’s gel test was devised as a joint government project between the DOD and the DOJ, specifically the US Army’s Wound Ballistics Laboratory and the FBI’s Firearms Training Unit, with heavy involvement of both Col. Martin Fackler, MD and Jerry Hall, chief of the FTU at the time. 

The reason, of course, was the quest to find a duty round that wouldn’t fail to incapacitate a subject in the wake of the 1986 Miami shootout. 

The 12- to 18-inch standard was specifically arrived at from the side profile shot taken at suspect Michael Platt by FBI Agent Jerry Dove. Armed with a Smith & Wesson 459 (9mm DA/SA) loaded with 115-grain Winchester Silvertip JHP, Dove placed a shot into Platt’s right arm. 

The bullet failed to completely traverse the chest, stopping short of the heart and failing to cause an incapacitating injury. 

While it’s true that Dove’s was not the shot that stopped him (he was stopped by a hit to the spine from Agent Ed Mireles, quite possibly one of the bravest men to have ever drawn breath), it’s interesting to note that it was the shot that killed him. 

The bullet perforated a number of vessels (likely including the subclavian artery, if not the aorta), causing internal bleeding and eventually his death, but it did stop short of the heart. You can listen to Ed Mireles describe it here (skip to about 1:25:00).

Also retired FBI agent Hilton Yam describe it here, starting at about the 7-minute mark.   

So, the 12- to 18-inch standard exists because it’s on the higher side of the penetration needed to perforate the heart and take an opponent out of the fight. 

Then, we consider ballistic gelatin itself. 

What Is Ballistic Gelation? 

Ballistic gelatin is a substance that creates an aggregate of human tissues. Obviously, the human body is made up of a number of different tissues (muscle, bone, fluids, tendons, etc.) and they all have different physical properties. 

While ordnance gelatin has been in use in various capacities since the 1950s, it was Dr. Martin Fackler who arrived at the formulation that’s used today. The idea, of course, was to find a reproducible test medium that would (somewhat) accurately predict what would happen on the street or the battlefield. 

His process probably wouldn’t be allowed now, but he would fire bullets into freshly killed pig carcasses (usually the leg, the thickest and fleshiest part of the animal) and measure penetration depth. Then, he would shoot the same load into a block of gelatin until the bullet penetrated to nearly the same depth. 

He arrived at 10 percent (by weight) gelatin to 90 percent water, using 250 bloom type A organic gelatin, a pork gelatin made by boiling down pig skin and bones. For those unaware, Type A is pork gelatin, and Type B is bovine/beef gelatin. He found that human tissue is very close in viscosity and density to porcine tissue. Ergo, pork gelatin was used. 

Further, the block has to be prepared by mixing the gelatin into 140-degree F water and stored at 40 degrees F for at least 48 hours. Prior to bullet testing, the block is tested for proper calibration by firing a .177 caliber steel BB at 590 fps into the block, which must penetrate 8.5 centimeters (up to 3.75 inches) into the block. 

With first aid kits on hand for safety, shots are fired into the block from 10 feet. Ammunition is tested in bare gelatin through four layers of heavy clothing, drywall, auto glass, and two panels of automotive sheet metal, simulating the thinnest part of an automotive body. 

Those bullets and loads that can reliably penetrate 12 to 18 inches through all tests are deemed worthy. Those that are not are not. 

Now, the reason the FBI, the rest of the law enforcement community and the ammunition industry has stuck with this standard is because the street results have proven themselves numerous times over. Ergo, the standard was created and then validated in the real world. 

FBI Gel Test Standards In The Non-LE Context

The FBI gel tests led to a number of ammunition developments, part of which was dalliances with .40 S&W and 10mm, but also the advent of the bonded pistol bullet. 

Modern hollow points (HST, Gold Dot/G2, Ranger, Golden Saber) have some sort of bonding mechanism, locking the jacket to the core, unlike the cup and core bullets of the 60s, 70s, and 80s, and achieve far more consistent and consistently satisfactory performance in testing and on the street. 

It’s worth noting that rifle bullets underwent the exact same development in the mid-20th century for the same reasons. Bonded soft points like the Nosler Partition and Swift A-Frame became the default choice of discerning hunters because they have been proven to work very well. 

Generally speaking, it’s a good idea to use the same ammunition (caliber and bullet) that law enforcement does because most of the usual suspects (HST, Gold Dot/G2, Ranger, Golden Saber) have been proven to work on the street. 

However, the law enforcement context is not necessarily yours. John and Jane Q. The Public has no responsibility to intervene. It’s not our job to arrest or detain, and so on, but what does that mean as far as the hardware is concerned? 

12 to 18 inches doesn’t necessarily need to be a minimum standard for the armed citizen. While underpenetration and failure to achieve a stop is certainly not a desirable outcome, it’s also the case that a bullet that meets a bit less than the 12-inch standard doesn’t necessarily mean the difference between life or death. 

It’s also rare – although not unheard of – for the average citizen to have cause to fire through glass or a door. 

While it’s a good standard to adhere to, what’s “optimal” doesn’t necessarily apply to everyone. 

So, now that you understand a bit more about the FBI gel test standards, you can hopefully see why they’ve endured and why they are a good baseline – though not gospel – for ammunition performance.