I started using the M1911A-1 pistol in 1968 and carried one during two combat tours in Vietnam (airborne infantry, pathfinders). Issued ammunition was either Ball or Tracer Ball. I prefered the tracer ammo because it allows rapid adjustment of fire into the target. I have used, and seen others use, the .45 pistol in combat situations on several occasions, and I do not recall a single customer complaint.
For decades many people kept a big segment of the gunsmithing industry going with various modifications of the 1911-style pistols for improved accuracy and/or functioning. Today the majority of 1911-style pistols being produced incorporate some of these improvements in standard production pistols, and many of these are capable of feeding, firing, extracting, and ejecting various ammunition types with greater reliability than anything available during the first three-quarters of a century of the 1911's life span. Ammunition has also changed considerably, with much improvement in functioning in a broad range of pistols. Magazines have also been improved somewhat.
But there is still nothing available with the reputation for reliability in function that the standard 230-grain ball ammo. All of the major ammunition manufacturers have held military contracts at various times, producing mil-spec .45ACP ammunition by the millions of rounds, and all (Federal, WW, Rem-UMC) continue to produce ammunition that meets those standards.
With a modern pistol produced by the reputable companies, equipped with modern magazines of good quality, and loaded with modern ammunition of any type by reputable manufacturers most people will never experience any difficulties during actual defensive use. However, just about everyone using the currently popular "self defense" loads (hollow-points, etc) for extended periods of time will experience some ammo-related problem during practice or training sessions.
Very, very few people using good quality pistols and ball ammunition will ever experience such problems at any time.
In my opinion it is all about consistency, reliability, and training. You must function test every element (pistol, magazine, ammunition) and train with them regularly. Beyond that, you make your choices and live with the results (or not).
Nothing wrong with good ball ammo in the .45 pistols. It works more consistently than anything else and as long as you do your part right ball ammo will get the job done.
And none of the above touches on the issues of people practicing and training with ball ammo or reloads, then carrying the high-performance self-defense oriented ammo for defensive use. I've seen quite a few surprised users find that their super-duper 185 grain JHP's won't shoot to point of aim, even at modest distances. I've seen others with pistols they know to be at or near 100% reliable during practice, then find that the first or second or third round of hi-performance ammo from the magazine stove-pipes during feeding, sometimes jamming the bullet back into the case, and locking up the action. Many (in and out of the LE community) have never received sufficient training, or practiced the drills for clearing the piece and getting it back into operation rapidly, so they just stare at the nonfunctioning piece in their hands with a confused look on their faces.
Consistency, reliability, and training.
My $0.02 worth.
