What Filler Rod for Cast Receiver?

[86thecat]

Ready to weld up a G3 with a cast Century receiver. Does anyone know the alloy of receiver and trunion?
What is the best TIG filler rod for this?
Thanks.

[tump]

a cast receiver is stainless steel. the trunion? someone will be along soon to help.

[86thecat]

I got lucky surfing for this info and would like to see if anyone here can confirm what I found.
The Century Arms cast G3 receivers are 17-4 precipitation hardened stainless "hot straightened to ensure flawless function and heat treated to 42-47RC" and the trunion is chromoly so 17-4 filler should work.
Since the stainless is magnetic my guess was a 400 series which tends to crack at welds so it's good news to find they are 17-4, much easier to weld.

[dirty8]

You can use regular stainless steel filler rod (308L) or stainless steel wire from the blue spool which Harbor Freight sells. The wire is 304 stainless, which is a good filler.

[40mmHEDP]

I used 308L.

These receivers weld up real nice with the trunnion.

No issues.

[86thecat]

Thanks,
If I can't find the 17-4 today I'll use 308L.