chrome or nickel plating rifle parts

18 June 2012, 20:34

I'm trying to finish up a build with an SMLE No.4 action. As usual, the bolt has "military clearance", that is, rattly loose as it slides back and forth in the receiver.

I'd like to take up some of the clearance. A plating of .001-.0015" thickness would tighten things up nicely. I don't care if it's shiny or dull, chrome or nickel, as long as it's in the right thickness range and doesn't change the strength of the underlying metal.

Has anyone dealt with a plater who will do single pieces and doesn't mind gun parts? It's just a bolt, no FFL stuff would be involved.

18 June 2012, 20:54

mete

Chrome is commonly used to build up worn shafts so that's what you want for your bolt.Make sure you specify HARD chrome.
For nickel specify ELECTROLESS nickel .That's also a harder type.

19 June 2012, 06:45

SR4759

quote:
Originally posted by TRX:
I'm trying to finish up a build with an SMLE No.4 action. As usual, the bolt has "military clearance", that is, rattly loose as it slides back and forth in the receiver.

I'd like to take up some of the clearance. A plating of .001-.0015" thickness would tighten things up nicely. I don't care if it's shiny or dull, chrome or nickel, as long as it's in the right thickness range and doesn't change the strength of the underlying metal.

Has anyone dealt with a plater who will do single pieces and doesn't mind gun parts? It's just a bolt, no FFL stuff would be involved.

Put a cross screw through the rear sight ears and put a little tension on it.
You might want to read up on the dangers of hydrogen embrittlement and stress corrosion cracking. Some of this can happen when you plate heat treated steels.

19 June 2012, 08:47

kcstott

quote:
Originally posted by SR4759:
quote:
Originally posted by TRX:
I'm trying to finish up a build with an SMLE No.4 action. As usual, the bolt has "military clearance", that is, rattly loose as it slides back and forth in the receiver.

I'd like to take up some of the clearance. A plating of .001-.0015" thickness would tighten things up nicely. I don't care if it's shiny or dull, chrome or nickel, as long as it's in the right thickness range and doesn't change the strength of the underlying metal.

Has anyone dealt with a plater who will do single pieces and doesn't mind gun parts? It's just a bolt, no FFL stuff would be involved.

Put a cross screw through the rear sight ears and put a little tension on it.
You might want to read up on the dangers of hydrogen embrittlement and stress corrosion cracking. Some of this can happen when you plate heat treated steels.

Just ask for a post plate bake, 3 hours at 200 degrees C will do it.

19 June 2012, 14:32

mete

SR4759, Hydrogen embrittlement can occur as a result of plating hardened steel.As mentioned post plating heating will correct this.
Stress corrosion cracking is a different thing. That you get on cases that haven't been annealed at the neck.

19 June 2012, 15:23

hawkins

Enjoy it for what it is. If you close tolerances down to one thou you will bind
up some day. It was made to work under bad
conditions.

04 July 2012, 05:43

kolob10

Electroless nickel is the way to go. It is a chemical process and you can specify plating thickness up to .001". It is more corrosion resistant than hard chrome. I've used it in several projects.

04 July 2012, 06:39

ted thorn

Polycoatings of the south is who we use for electroles nickel and you can get it very thick!!! Add teflon and it becomes polyon and it is very tough. We have molds with millions of cycles and it is still on

http://www.polycoatingssouth.com/

07 July 2012, 03:20

lawndart

Another thought is a Nickel Boron coating. In the trade it is called EXO/Failsafe. It goes on thin, and is especially good for moving parts. It is used on AR-15/M-16 bolts/bolt carriers, hammers, triggers, barrel extensions and upper and lower receivers. Grime and carbon from full auto, suppressed shooting wipes away with formula 409, or Windex and a paper towel/shop rag.