If you are packing an M4 style carbine; M193 ball is just fine. The 55gr ball gets almost up to full speed in a 16" carbine barrel, and is ballistically good out to 250-300 yards. Bullet tends to roll over and break at the cannelure in soft medium and comes apart on impact with very hard targets. Glass penetration is adequate, but not stellar. Of course feed and function are good in M4 style carbine. If you use Federal XM193, you are carrying what is considered a MilSpec load. One of the biggest problems I see in the AR world is use of inadequate ammunition that does not gas the weapon sufficiently, and bullet designs that are too soft and tend to blow up on contact with anything, w/o adequate penetration. While a lot of agencies think that the AR and 5.56 round are over penetrative, research shows that is not true, and Agency heads just are not aware of the problems related to soft tip or hollow point rds in an M4 style weapon.
Now, if you are carrying M855 ball in your Carbine, then yes, you can have an over penetration problem, even though the 62gr ball bullet will not get to terminal velocity in a carbine barrel. Remember, the M855 ball round was designed for use in a M16A2 rifle, to give the rifle body armor defeating capabilities with it's Tungsten penetrator, at up to 600 yds.(As in Russian Infantry in the Fulda Gap). Use of M855 ball in a carbine is basically contraindicated. Remember the Battle of the Black Sea(Mogadishu). Troops were "Ice Picking" combatants with several hits before the person would succumb. The 855 ball round was going thru and thru with no disruption or disintegration in the target due to lack of correct terminal velocity, hence no stopping effect. The ARMY, God bless 'em, changed our main Infantry weapon from a full rifle to a carbine due to MOUT and never changed the ammunition. Well, correction. That is being done now with the new M855A1 load, and it is up to speed in a carbine, and penetrates like a it should, as it is basically an AP round.
Black Rifle, Vols 1, & 2
IMHO, anyhow. As always, YMMV. Thanks, Gentlemen :flag: