Barrel length is only 4.5". You are referring to the FNP-45 Tactical which has a 5.3" threaded barrel.
FN's website says the width is 1.58", I think this is the thumb safety widths. The grips on a G21 is 1.34". I believe the 1911 is 1.2-1.25" thick in the grips, but the frame/slide is probably atleast a quarter inch thinner than the FNP and G21.
"The Marines I have seen around the world have, the cleanest bodies, the filthiest minds, the highest morale, and the lowest morals of any group of animals I have ever seen. Thank God for the United States Marine Corps." Eleanor Roosevelt, 1945