If that is a flintlock, first put together the frizzen spring, frizzen bridle, and frizzen, on the front side of the lock. Those parts are easily identified, and can't be confused with much else. The same with the long pivot screw that holds the frizzen into the bridle.
No, find your hammer, and the tumbler. They are also unique. YOu can set them asign as one assembly, while you find the other parts.
You should have two springs left. The mainspring is the longer one. The sear bar return spring is the little one.
What you have left is the Sear bar- and L shaped piece that has a fitted NOSE on it that fits into the half cock, and full cock notch of the tumbler. There is a bridle, which provides support to the tumbler and sear bar when when they are installed. And, there is the fly. It should be the smallest piece you have that is not a screw! It fits in the rear face of the tumbler, so put it aside with the hammer and tumbler.
To assemble the first time, leave the Springs OUT. you don't need tension on parts until you are sure you have put them in correctly! Now, figure out which screws fit which holes, in the lock plate, by trial and error, and then measure their lengths to compare with the parts that are being held. Try the screws in the bridle to see how the heads of the screws fit when the screw is fully seated. Only when you are pretty sure you have the correct screw for each part, do you attempt to put the parts back on the lockplate.
I like to put the tumbler through the lock plate first, because that is the biggest hole, and I want to be sure that the tumbler turns freely, with no burrs or dragging against the lock plate, before I begin adding parts. Leave the hammer off. Next comes the sear bar, with its nose put into either the half cock or full cock notch, just to hold it in its location, while the fly is put on the tumber, carefully, and then the bridle is fitted over the top of both the tumbler, fly, and the searbar. Now, check to see that the fly works properly, to allow the tumbler to turn forward past the half cock notch. On some locks, the fly is a triangle shaped piece with a small hole in it that fits on a pin in the tumbler. If you put the fly on backwards, it won't work. On other locks, the pin is fixed to the fly, and fits into a hole in the tumbler: you can't put the fly in the tumbler wrong!
Always check every part you install to make sure it moves freely against its counterparts with just your fingers moving the parts. If there is any drag, STOP! and find out what is causing the drag. Don't crank those screws down too tight. This more like a swiss watch than your car! OIl the parts as you put them into the lock plate, as well.
Before I put the hammer on the tumbler, I like to install the sear bar return spring, so that there is some tension on the sear bar, and the sear nose in the notch of the tumbler when I locate the hammer.
If you did not put a witness mark on the hammer before removing it from its stud on the tumbler, You will have to find out on which side of the square stud do you place the hammer's square to make the hammer function properly. I like to put the tumbler on the half cock notch, because I know that the hammer will be almost perpendicular to the lockplate when the tumbler is in that position. If the hammer fits on the square stud in that position, I go ahead and release the sear from the tumber, by lifting up against the sear bar, and let the hammer go forward. It should go all the way forward to the hammerstop, with the jaws near the flashpan. If this is true, you have the hammer set on the correct side of the " square " stud, on the tumbler, and you can tap it down and put the hammer screw into the tumbler. Oil the screw and the tumbler's hole, and put a witness mark on that hammer and stud with a scratch awl, before you cover that up with the head of that large screw.
Now, with the hammer forward, you can install the mainspring, as there will be the least amount of tension placed on the mainspring arm with the hammer down. There is a " horn", or "stirrup", structure on the front of the tumbler to which you fit the longer arm( working arm) of the mainspring, before compressing the spring lightly so you can move it back into the holes provided under the bolster, and in the lock plate.
That should complete the assembly of the inside of the lockplate parts. Go back now, and install the frizzen spring on the outside of the lock plate. Make sure all contact surfaces are oiled, and that all parts move freely before you put the three springs back in the action.
I recommend using padded vise grips to compress the mainspring and frizzen spring just barely enough to get them into the lock. don't over- compress these "V" springs or you risk breaking them.
If your lock uses a coil spring, there is usually a " strut " that goes down the middle of the coil spring, with a hole in one end that appears when the coil is fully cocked. Put a paper clip, or some other wire through the hold to hold the coil compressed, and then release the hammer. The coil assembly should come out easily then.
TO put them back, if you have taken the " keeper Pin" out of the strut, you first have to put it back. Get a friend to help you if needed. Put the strut back through the coil, and use needle nose plyers to push down on both sides of the coil to compress the spring until you can put that paper clip or wire back into the hole in the strut. Now you can put the spring back into the lock. Once installed, cock the hammer to put the coil under tension again, and then remove the wire or clip from the hole. YOu will figure out any clearance problems involved in doing this as you work on the lock.
I have not mentioned it, but I am assuming that while you had the lock disassembled, that you polished all contact points in the lock to a mirror finish, removing tool marks, so that there is NOTHING dragging against any other part or the lock plate.
Most of what I do in tuning locks for other shooters is polishing and smoothing rough surfaces to remove drag. The less drag, the faster the parts move, and the faster the action will be.
