So I would say yes, go with the 55grain stuff, it tumbles, and causes worse wounds.
BTW, the Russians are way ahead of us in military bullet (slug, not cartridge) technology. Their 5.45mm bullets use a hollow space just behind the tip, then a steel penetrator, then a lead "driver". The slug is balanced for accuracy in flight, and as soon as they hit flesh, the driver and penetrator push forward into the air space, causing the center of gravity to flip, and the bullet to keyhole like mad, always coming out backwards or sideways. The Afghans and Chechens really fear them, and call them "poison bullets".
Another "field expedient" for your .223 ball ammo is to take strong wire cutters (dykes) and clip off the front 1/8" of your bullets. This is hell on long range accuracy, but ensures the slugs will be keyholing and tumbling into their targets. I have not done this, but some old VN jungle fighters (close range engagements) told me about it.
The 55 is better stabilized than the 62 in any barrel. If you want something marginally stabilized like the 55's were in the the 1-14 original M-16 you would need a slower twist or a heavier bullet.
A better effect is the Nosler Ballistic Tips or the Horandy TAP. They "explode" on impact and penetrate 1/4 steel, no problem. With their polymer tip, the bullets have a natural lubricant for steel and other hard targets.
Also, a grinder works perfectly on 55 gr ball for nipping the tips. The result is a very jagged wound channel.