Well, being an old 1903 you should take it all the way apart anyway now that it is yours. You should also be ordering a complete new spring set from Wolff springs and change them all, even the firing pin and extractor springs. Also, IMO, the disconnector leaf springs sometimes fail on these things. The grip screw often presses up tightly against the disconnector spring and sometimes, after a short 80 years or so, this causes a stress failure. A symptom would be sudden inoperability. Numrich Arms, Sarco and others carry the leaf spring. This spring also powers the sear and the trigger so its failure is bad news all around.
You don't mention it, but if your hammer came out, you also removed the safety. Being made in 1904 - 1908 we are talking about either a version 1 or a version 2. [My current 1903 is a version 1/2 transitional, but my first one was a straight version 3.] This means you also first removed the safety screw on the right side, then you pulled out the safety. However, the safety won't normally move unless the mainspring pressure is taken off the sear. This means you also removed the grips, and then you removed the lower pin holding in the grip safety/backstrap. Once you also messed with the backstrap pins and released the grip safety you also took tension off the mainspring and the sear spring and totally loosened everything up. It is very possible that by pushing down the disconnector you simply managed to slip something to the wrong side of the spring leaf. No biggie. Fixable.
Sadly you may as well go ahead and totally strip it and clean the dirt out of the channels with a Q-tip while you are at it. If you find a broken leaf spring, replace it. Replace all the springs, especially the 100 year old recoil spring. Either way, 'reassemble in reverse order.' No doubt you will notice an annoying tendency of the sear piece to turn upside down at annoying times during reassembly. Holding the pistol upside down and poking the sear with toothpicks helps keep it in place long enough to align the disconnector and slide that pin in. I use two or three wraps of scotch tape around the grip to hold the grip safety inplace against the mainspring tension. Aside from ending cramps in my hand this frees me to put the gun down and go get a cup of coffee before trying again. It also allows me to hold the toothpick in the hand that is no longer tied up squeezing the grip safety. For the hammer, once almost aligned, I use a pre smoothed (use emery cloth to remove any ridges or flash from the nail) size 6d nail (generic) from the right side safety hole to push everything into perfect alignment, then push the nail out with the original pin (which is of course the actual safety which does double duty as a hammer pin) from the left side. All pins should be inserted and removed to the left side only (a rule written by Colt).
You can find original take-down instructions and diagrams for the pistol on coltautos.com. Search also while there for similar data on the Colt 1908 .380. The drawings and other info applies equally to both. Don't be confused by the little plunger pictured there on the back of the recoil spring guide or the thing that looks like a second trigger bar. Those drawings are of the version 4 pistol with a magazine safety. Ignore pictures of non-pertinent parts. Pay attention to which direction the different springs curves face in the Colt diagrams. There is a good (free) video of total disassembly and reassembly of a version 3 available on U tube.
Hope this helps.
Last edited by superc; 08-31-2010 at 08:46 AM.