Quite a bit of fair advice here. You really shouldn't become too concerned as to relative effectiveness of the .30 CaliberU.S. Carbine round. Yes, in the 110 FMJ version it will exhibit less performance that one of the expanding projectile types. However, as noted accurately above, the JHP / JSP types will provide exemplary performance within any reasonable combat range. IIRC, the Carbine was alleged [ by U.S. Ordnance Corps ] to be effective out to 300 yards, which IMHO is stretching it somewhat. Within 200 yards with the proper ammunition it will serve as required. Even now, years it's original inception the little 'Carbine, Caliber .30 M1' remains an excellent choice for pretty much any limited range 'area's defensive purposes. It's light weight short O.A.L., rapid fire, adequate magazine capacity, above adequate sights, etc. There are a few caveats though, prior to declaring 'your' Carbine as for for duty.
1st ) It MUST function perfectly, & with your ammunition / load of choice. If at all possible, if it's an older production weapon, & or U.S.G.I. Surplus, especially an IMPORT example you should absolutely replace any / all of the relevant springs to ensure proper function when needed. NOTE that this testing includes any / all magazines you may use with it. [ Magazine springs do loose tension over the years. ]
2nd ) Test fire your chosen ammunition for BOTH feed reliability, but also for accuracy in your particular weapon.
Once ALL of the above has been accomplished, you 'should' by good to decree your handy little M1 Carbine as 'Good To Go' ! AND I'm closing, also noted above is how similar the .30 Caliber Carbine load is as compared to the .357 Magnum loading. Have you ever noticed the amount of people using a short little .357 Magnum Lever Action Carbine, as in the Winchester 94 Trapper, Marlin, Rossi, Umberto, & quite a few others. They all make an excellent short+ range, extremely handy weapon. Just remember to feed it properly, update springs & clean occasionally. OK, I hit you will no longer worry too much about using an M1Carbine for pretty much what it was initially designed for, As an short range, light weight, uncumbersome weapon for individuals who were not very well served by being issued the full sized 'main battle rifle'.

Best, dpast32