Machining and heat treating

[ryanyates28]

Hi
I'm relatively new to heat treating , can someone tell me if I used pre heat treated 4140 to make a revolver frame, cylinder,barrel, would it lose its temper or hardness during machining and would I need to treat it again after
Thanks

 

[Myrmidon]

No hard is hard if it's thru hardened

Unless you some how manage to raise its temp to like 1000 degrees machining it and hold it there abit.

 

[ryanyates28]

No hard is hard if it's thru hardened

Unless you some how manage to raise its temp to like 1000 degrees machining it and hold it there abit.

Myrmidon thank you for your reply
so if I use cooling / cutting fluid the temper and the hardness should remain the same

 

[Myrmidon]

What level of hardness do you need on these components, 4140 HT is only like 35rc.

 

[ryanyates28]

What level of hardness do you need on these components, 4140 HT is only like 35rc.

I need about a somewhere between 28-32rc

 

[ryanyates28]

I need somewhere between 28-32rc

 

[ryanyates28]

I need about a somewhere between 28-32rc

Sorry my English was no good in that reply

 

[david n]

I make critical gun parts day in and day out outa 4140HT.......................it's basically the industry standard.

 

[ryanyates28]

I make critical gun parts day in and day out outa 4140HT.......................it's basically the industry standard.

David n do you do any tempering or treating after machining them also does machining cause any stress to get steel thanks

 

[david n]

nope....................unless the part calls for a hardness greater then the standard 28-32 RC. Then is goes out for heat treat. Has nothing to do with the machining process.................if you are drastically changing the HT properties in how you machine the part, you shouldn't be making gun parts or any parts for that matter..............

 

[ryanyates28]

nope....................unless the part calls for a hardness greater then the standard 28-32 RC. Then is goes out for heat treat. Has nothing to do with the machining process.................if you are drastically changing the HT properties in how you machine the part, you shouldn't be making gun parts or any parts for that matter..............

David n that's great thank you

 

[triumph406]

I need about a somewhere between 28-32rc

4140 pre-hard as luck would have it.

What loads are you shooting? Did you do any analysis, or just copying an existing design and load?

 

[plastikdreams]

Knows nothing about materials or machining...wants to make a gun...sounds legit.

 

[ryanyates28]

4140 pre-hard as luck would have it.

What loads are you shooting? Did you do any analysis, or just copying an existing design and load?

I will be shooting 455 Webley rounds and I am copying a Webley Mk6 gun that I already own thanks