Does your 1911 rattle when you shake it side to side? Big deal. What that means is you probably have a Colt. Now don’t get me wrong, I love Colt’s. That is the only 1911 for me. What that rattling really means is that your gun was not fit very well at the factory.
If you were to buy a truly custom gun it shouldn’t rattle. They are made to demanding specs that call for tight tolerances. Some factory guns don’t have a lot of play, but most companies don’t put enough time into them to really care about the fit of your gun. They are simply trying to give you a good value with a decent fit.
It’s true that you are loosing some accuracy by having one of these old rattle-traps, but for most shooters, i.e. non-bullseye shooters, it will never make a difference because they can’t shoot well enough to see the difference on paper. If you are using the gun for defense or plinking go ahead and enjoy it. A little rattle never hurt.