Ditto what tatjana stated.
If what you read was the FBI report, or a detailed summary, you will notice that the best results were not FMJ. If you perform the test tatjana describes, use JHP, TAP, or any other high performance bullet.
Another test preformed here was use plastic milk jugs (1 US GAL or equivalent). You will need several filled with water. Place them in a row. Use FMJ first. (have SEVERAL lined up for this one). Shoot. Notice how many are damaged. Replace said damaged milk jugs. Use a JHP, JSP, ect and repeat test several times. The best results were from TAP. 1-milk jug dead, second one had a ding, but no water leaking out. Our carry ammo: 1st milk jug, dead; second seriously wounded; third, unharmed.
Our duty ammo is Federal .223 Premium 55 grain Sierra Game king BTHP. Good, but not the best.
Hope this helps.
Art in KY
PS My carry AR15 (16" Bushmaster) with this ammo is LESS likely to over penetrate then my Glock Model 22, .40 with 180 grain Hydro-Shock.(sp?)
I am not responsible for misspelled words while the spell check is down.