My agency hosted ballistics workshops last November. ATK was first. The 147gr HST load was what I was really interested in from them. Main test gun was an issued 4" M&P. We also conducted bare gel tests using a 3.5" M&P9c and a 3" Kahr PM9. This was done to see the effect of velocity loss from a shorter barrel, when compared to the bare gel shots from the 4" gun. Short answer, 4" to 3.5" no difference. When going down to the 3" gun, there was some difference. But very little, maybe an increase in penetration of .5".
The interesting thing occurred the following week when Wincheester came out. We kept the actual box of ammunition from ATK and reshot the 147 gr HST against the Winchester 147gr Ranger T loading. In one test we had two failures of the HST to expand. One round looked like the round pictured. I asked for the test to be reshot. The second time the round failed to expand at all. The thing looked like an unfired bullet.
My agency ended up switching to the Winchester loading. While the failure to expand did play into the decision, it wasn’t the main factor.
I’m not a ballistic engineer. But I do know that when dealing with bullets, sometimes weird shit happens. It’s because of this concept that I’d still have no issues carrying the 147 HST in my guns.
If I were buying carry ammunition and had to choose between the Winchester 147 gr Ranger-T loading and the Federal 147gr HST, I probably buy which ever one was cheaper.
There are no magic bullets. If the round fails to expand then shoot them again!