Groupings of the size of a Quarter are easily accomplished at 50 feet and once in a while I do a lot better with a Colt Gold Cup. Even my Gov't Models will shoot under a silver dollar at the same 50 feet - and that is with the standard military sights. They say that military versions were inaccurate because they had to be loose to be reliable. I have not found that with the ones I own. I've got a 1943 Military Colt that will (in a pinch) shoot good enough to compete with - except the sights are not conducive for that purpose as I get older. Yes, it rattles and was actually used in WW2 but somehow it shoots like the Dickens!
There are some things that gave the M1911 and M1911-A1 a bad reputation for accuracy. Back in the day, the most experience a great many men had with the M1911 platform was during training as they entered the military. Most had little to no firearms training, especially with handguns, so they did not enter with the skills necessary to accurately shoot the M1911 not did they have sufficient training time to fully learn those skills.
The tiny sights, although I find them great for precision shooting, are not particularly visible in bright sunlight and they do hinder accurate timed and rapid fire shooting.
The trigger pull on military issue M1911's tends to be heavy and gritty, definitely not conducive to accuracy.
Generally speaking, military issue M1911's were not really inaccurate, but were given a bad reputation that is undeserved. A rattling M1911 is capable of reasonable accuracy, the government standard was an average of 5 inches at 25 yards, 10 inches at 50 yards. This is plenty accurate for a loosely fit combat handgun and many issued M1911's were capable of even better accuracy.