Arnald

UZI semi sear need to be hardened?

Location:

6 posts in this topic

Hello, Im new here.

I have recently been collecting parts for a semi only UZI build. I have a few more parts I need to buy.

 

MY Question IS: If I have a smg sear cut on a mill by a machine shop, would the newly cut semi sear need to hardned before use or woul it be good to go as is?

 

Share this post


Link to post
Share on other sites

I'm not a subject matter expert, but I think it would be good to go as it is. 

-KristopherH

Share this post


Link to post
Share on other sites

Yes, no, maybe so.  It all depends.  For a few shots, a soft sear may work fine.  For many shots, maybe not.   How many shots is a few?   How many shots is many?  A soft sear might make your semi Uzi into a full auto when it wears or breaks.   I used to work as an inspector in a manufacturing facility.  Almost every day I did hardness testing on stuff that had been through heat treat the previous night.   All of our stuff was machined, then heat treated.  If it failed the hardness test, it was scrap.  If your sear is machined from pre-hardened stock then it may be okay.  Or not.  Looks like you are taking an SMG sear and having it machined.  I would bet my left nut that SMG sear is hardened.  Depending upon the material and the hardening method, it may be equally hard throughout the piece or maybe hard only on the surface in which case the machining may expose softer metal underneath.  Depending upon the material, the machining method and the skill of the machinist, the piece may become either harder or softer during the machining.  You might want to seek a second or third opinion on this one.

Good luck,

Kevin in NC

Share this post


Link to post
Share on other sites

OK, Thanks for your input!

I had been mulling over in my head the thought of whether or not the SMG sear would be surface hard only or hard all the way through. 

I just wish I could find someone who KNEW ( from experience or other ) what they were and  / or what needed to be done regarding hardening the newly cut semi sear.

Share this post


Link to post
Share on other sites

Posted (edited)

41 minutes ago, Arnald said:

OK, Thanks for your input!

I had been mulling over in my head the thought of whether or not the SMG sear would be surface hard only or hard all the way through. 

I just wish I could find someone who KNEW ( from experience or other ) what they were and  / or what needed to be done regarding hardening the newly cut semi sear.

Is your SMG sear marked with an X? If so, it was tested by IMI for hardness and presumably found to be acceptable. 

If I understand correctly, the Uzi sear was intentionally designed to be softer than the bolt, so that it would wear before the sear engagement area on the bolt. That makes sense to me, as a small part is going to be easier and cheaper to replace than a block of steel. 

Against better judgement, I use a semi-auto sear in my registered bolt Uzi SMG and it has stood up pretty well. However, I understand there are some risks to doing it this way. I am inclined to believe that a trimmed down SMG sear would be just fine in a semi-auto Uzi.

In the end, it is entirely up to you. It's your gun and your personal tolerance for risk.

Good luck.

In Liberty,

KristopherH

Edited by MontanaRenegade86

Share this post


Link to post
Share on other sites

You might try weaponsguild.com they have probably talked about it there. Lots of builders on the site, but you need to setup a login.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now