Heat treating ejector tip in finished receiver..

[NapaCountyShooter]

So I went to Circle S to test out my first Romy build today and it fired, but I fricken cut the ejector tip too much and it caused constant fte's leaving the spent case in the receiver.
From what I understand, I can get some material welded to the end of the ejector and file to fit. If so, what's the drill on heat treating the tip? Frustrated.

[Fern]

Did you heat treat the ejector tip during assembly?

[NapaCountyShooter]

Did you heat treat the ejector tip during assembly?

Yes, but won't I have to re-heat treat the material that's welded on again?

[Domingo]

On one of my builds I had the same problem.
I welded some material and did not heat treat
afterwards the weld seems to be hard enough
I have about 2000 rounds trew and dont see any
Signs of stress or mushroom on the tip

[Richard Erichsen]

Yes, but won't I have to re-heat treat the material that's welded on again?

You need to be very specific about filler - if it is not tool steel you can't harden it anyway. Most garden variety weld rod is mild/low carbon steel, as in NOT hardenable. If the rod doesn't specify it's alloy, it's guaranteed to be low-carbon steel (1008-1020 series or equivalent). You can test this by heating the rod to bright red then quenching in water or oil and vigourously agitating (swishing back and forth). If it hardens, it's high carbon steel. If it does not, you'll know it's low carbon.

While it is important to harden the tip of the ejector and then temper it to reduce brittleness for long life and durability, it will not mushroom or fold over until several thousand rounds are fired even if you forget. A typical receiver bought domestically (AK Builder, etc.) are tool steel - 1060, 1075, 4130, 4140 steel alloys which have more than enough carbon to be 25-30 HRC even before hardening.

Since there is wear on the rails, not just the axis pin holes, there may be some benefit (longer term) to full heat treat of the entire receiver to a final hardness of 40-42 HRC. However, without a quality furnace and good time and temperature control the receiver can warp using the "cave man" methods in the open air.

R