It helps if you have experience with Flash (or some animation tool) and photoshop. Not necessary though. I had barely any experience when I did it, and it took about 1-2 hours. These instructions will get you a full picture ( you will be able to see the floor and background) unlike my cropped version.
If you want to see an example, you'll find my cannon here:
http://www.spudfiles.com/forums/updated ... t9166.html
Now for the instructions:
Ok, it was pretty simple/difficult.
If you end up doing this just give me credit for help and the idea. 
First, find a place where you have good lighting, so you will not need a flash. It needs to be large enough for you to rotate the gun 360 and not hit things. If it is not bright, add a light or two. A camera flash ruins the shot.
You will need a good camera, a very stable tripod, and something you can mount your gun on. I used a 7 megapixle camera (4 or 5 is fine), a crappy tripod, and a umbrella stand to mount the gun on. If the tripod you use is not stable, it will make things much harder. In my 360, you can see things jiggle a bit, because my tripod moved every time I hit the button. Because of this, I had to tediously edit the pictures to make them look less choppy. It still turned out kinda bumpy in the end.
Mount your gun on something stable, that you can easily turn your gun on. If you have a small turn table, USE IT. I had to rotate my gun on the pole, but if the pole rotates the gun, even better.
Basically, keep the camera still, and make sure the gun only rotates on one point.
Set up the gun mount (turntable, umbrella holder, homemade, whatever) in the middle of a clear open space. I used the garage, and you can't see much junk in the background. Put your gun on the rotating mount, and set up your camera so that you can see the whole thing. Rotate the gun some more and make sure the whole gun is in the picture for the whole rotation. If you don't, you will be in trouble later on. If your gun refuses to balance, put a wight in either the chamber or barrel to even it out.
Turn on all the lights, and turn off the flash of the camera. Take a picture, and make sure it is not blurry or dark, and that you can see everything. Make sure the camera did not move. Now, get ready for the stop-motion photography. Get a piece of paper, and rip it into pieces. Set them up around the gun, like a clock. I used 16 pieces of paper. Make sure the pieces are spread evenly in a circle. These are the spots you will turn the gun to for each picture. (see the attachment)
Now line up the gun with the piece of paper facing the camera, make sure everything is set, and take the picture. Rotate the gun to the next piece , and take another pic. Keep taking them until you go around the circle. Make sure the camera stays still the entire time. If not, you will need to start all over again. Now, view the pics on your camera. Quickly scroll though them, and it should look like your gun is rotating. If not, or it jiggles too much, redo the whole thing.
Now, for the
part. First, If you have photoshop or flash pro, great. If not, you can still do it for free. Download PHOTOFILTRE and ADOBE FLASH CS3 PROFESSIONAL. Both should be free. Flash is a 30 day trial. If you are better at making GIFS or using some other animation program, just use that.Download the pics from your camera to your computer, and put them in a folder called "animation" on your desktop. Make another folder called "edited". I am assuming you are on winblows, here. Now, open PHOTOFILTRE. On the top bar you should see a pulldown menu under "tools". Click "automate/batch" Choose the "animation" folder as the source, and the "edited" folder as the output. Go to the image tab and check "image size" Change width to 550 and hight to 400, to match the default in flash. Make sure "preserve ratio" is checked. Go to the "Action" tab and hit ok. Now the program will make the pictures smaller.
Open the "edited" folder and open flash(or whatever). Click "flash file actionscript 2" At the top, highlight frames 1-16 (or how many frames you have) and right click "convert to blank keyframes". Now click the first frame, and put your first picture on it. line up the background and the picture. Do the same for the rest of the pictures on the next frames. Now click the dropdown menu, "file" then "publish preview -flash" If you find it looks good, then go and click publish. If not, you got some editing to do. When you are done, go to "publish settings" and make sure the files appear on the desktop. click publish. It should be a swf file. Upload the file to your post. Make sure the file is under 350 kb. If not, you need to compress the jpgs.
Need help; look it up or experiment. That is how I did it.
Last resort = Me
