ShootistPRS
New member
Dr. Fackler used ballistic gel at a precise ratio and at a precise temperature. He even found a way, using a BB to "calibrate" gelatin. He also used what is called a "Fackler Box" that uses water and freezer bags in a long apparatus that could correlate penetration compared to ballistic gelatin. The Fackler box is a great way for the common man to test bullets for both expansion and penetration. If I remember correctly (possible) it was necessary to multiply the penetration in water by .557 to get the amount of penetration in gel. It is a very accurate way to get repeatable results when testing bullets for terminal ballistics. I built two (the first one blew apart on the first shot) and tested both pistol and rifle bullets. The box is not really very portable and you have to have enough water to fill new bags each time but you get repeatable results every time.