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some Dykem and you can immediately see where the metal is being removed.

To increase the performance of a file, apply file chalk freąuently to the file’s face to keep chips of metal from catching in the teeth. A file card makes it easy to clean out any metal chips that do stick. Any time spent cleaning a file will greatly increase the cutting ratę of the file, with fewer gouges caused by Steel chips caught in the toeth.

FINISHING THE PART

As you are near the finał dimensions of the part, change to the India Stones and abrasive paper. Because they cut morę slowly, they will help you avoid making mistakes and give a nice, smooth, uniform finish to the part. Internal parts don’t usu-ally need to be highly polished, but remove all file and machinę marks to give a Professional, ąuality look to the finał part.

When the part is completed, (See Figurę 7), install it in the firearm or the assembly of which it is a part. All you want to do is make certain that the part fits properly. If the part is to be heat treated, be very care-ful not to stress it while it is being checked for fit. For example, if a firing pin is madę from a relatively soft Steel, do not try

FIGURĘ 7 - The finished firing pin, ready for finał fitting and heat treating.

to fire a round, or even drop the hammer on it, until after it has been heat treated. Test-ing its function can easily bend or distort it. Once the part has been checked and finał fitting completed, heat treat it as reąuired. Follow this with function testing using dummy ammunition and snap caps and then live round tests. Your efforts should be rewarded with a part that is quite possi-bly far superior to the original, mass pro-duced, factory part.