1842 Tune Up

[hobbler]

Is there anyone that folks would recommend for a trigger job on an Armisport 1842 lock?

[William H. Shuey]

John Zimmermann, Harper's Ferry Arms is his shop, I believe.

Bill Shuey

[matt]

Are you just looking to reduce the trigger pull? Or are you looking to go whole hog and get everything slick and smooth also? If just reducing the trigger pull weight that is relatively easy. You disassemble the lock and silver solder a piece of brass shim on to the full cock notch and then file the brass down till you get the right weight you are looking for. Smoothing everything up so it is slicker than snot is a different story.
Matt
Winslow's Battery D 1st NY LT Artillery 9775v

[rachbobo]

I just went over the sear on an 1816 lock that was converted to percussion. The date on the plate is 1823 for what that's worth.
Even with a good gun grease it must have been about a 25 pound pull, uggh.
I disassembled the lock and inspected the full cock area of the tumbler. I could see it was kind of rough with a slight ridge.
A few strokes with a fine diamond file removed the ridge then I packed the area with lapping compound and using finger pressure alone squeezing them together worked the tumbler and sear back and forth for about 10 minutes.
I cleaned everything up and saw a nicely polished contact area.
I reassembled the lock and coated the innerds with a good gun grease and the pull dropped to around 8 pounds.
I could go over it again but I live by the rule that metal removed can not be replaced.

Bill Cheek

[Eggman]

Another option is to simply "Stone" the full cock notch. This provides much more delicacy than any file. I use the small Arkansas stone commonly used for knife sharpening found at any sport shop. The stone provides a glass smooth surface without digging into the metal endangering the hardness. It's also useful to have those magnification goggles on while you do this so you know exactly what's going on.

[rachbobo]

Eggman,
The Diamond files I use some call Swiss files or Jewelers files. Maybe 5/16ths wide at most and less than an 1/8th thick.
They come in all shapes, round, half round, triangle etc. They are much finer that traditioal files and are used for polishing, not metal removal.
They are somewhat pricy but worth the investment for fine work.
The lapping compound is really the trick.

Bill Cheek

[Eggman]

Yeah Bill it may be a Dutch thing. I always look for the cheapest route. I am getting satisfactory success with my little stone.

[Southron Sr.]

Another "lock job" that requires a bit more work is to:

Obtain some of those sheets of black, carborundum paper in the "Finer" grades.

Disassemble your M1842 lock.

Get a FLAT piece of steel and wrap a piece of the paper around it and then start polishing the INSIDE of the plate. Polish until the inside of the plate looks like a MIRROR. By this time you are using the 1200 grit paper. I quit polishing when I can clearly see the reflection of my face on the backside of the lockplate.

Polish that part of the tumbler and sear that rub against the lock plate.

Carefully, oh so carefully polish the "Full Cock" notch in the tumbler. Being sure NOT to change any of the angles.

Grind down your sear spring a little using a Dremel tool. You want to weaken the sear spring by about 30% of its strength.

Reassemble your lock and lubricate with a high quality grease.

CONGRATULATIONS YOU HAVE DONE A "TWO-FER!"

1. You have reduced your trigger pull.

2. Thanks to the polished surfaces inside of your lock, you have increased your "Lock Speed" which is a Good Thing!

Try It, You will like it!

[varsity07840]

I did the brass shim trick on an original 1816 lock and replaced the sear spring with a repro that was much lighter.

Duane