FWIW, I've used thousands of rounds of Winchester 9MM NATO and various brands of commercial ball ammo interchangeably for years in semi-auto pistols, revolvers and carbines. Chronographing the Winchester NATO in a variety of firearms showed that, while it is a little warmer than some US commercial ammo, it does not equal the velocity of most 124 +P ammo I've tested.
For example: Winchester 9MM NATO tested in a 5" barrel averaged 1206 FPS. Federal 124 +P HST averaged 1253 FPS, Speer 124+P Gold Dot 1262 FPS, Winchester Ranger 124 +P 1292 FPS, CorBon 125+P 1339 FPS. I never had a 7.848" barrel for testing, but in a 5.9" barrel the Winchester NATO averaged 1244 FPS . Results of course will vary,i.e., different days, different lots of ammunition, different guns even though same barrel length,etc., but you get the idea.........ymmv