Just to caveat what Bart B said about the 190 SMK through 308 service rifles, the Air Force team had to drill a gas relief port in their M14s to handle the added pressure, which is why that particular modification is still CMP legal for EIC matches. I don't want anyone to take the recipe Bart listed and fire it in a stock M1A thinking that it is fine, odds are they'd get a damaged oprod very quickly.
Brass life with the 190 load was very short (but brass life is generally very short from an M14/M1A platform), but the load did win matches.
With the introduction of the 175 SMK, pretty much everyone has given up on the 190's for High Power/EIC competitions as now they can use a 175 SMK "across the course" load.
Machine guns are awesome until you have to carry one.