Bren 30-06 barrel with fluted chamber

[cal50]

I have broached a lot of things but doing a 30-06 chamber flutes would be a tough one. I don't see any room to press a long broaching to get the depth or room for chips.

Hammer forging is not likely since the mandrel has to rotate with the rifling to remove and no way with straight flutes in the chamber.

I think the stub I cast was dated 1959.

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[Flying10uk]

I have broached a lot of things but doing a 30-06 chamber flutes would be a tough one. I don't see any room to press a long broaching to get the depth or room for chips.

Hammer forging is not likely since the mandrel has to rotate with the rifling to remove and no way with straight flutes in the chamber.

How do you think the flutes were produced then if they weren't broached or forged?

If the stub that you cast is dated 1959 I guess that it would be in the era of "spark erosion technology" but I don't know how good the process would be in this application, i.e. a gun chamber.

---------- Post added at 01:26 AM ---------- Previous post was at 01:17 AM ----------

I don't see any room to press a long broaching to get the depth or room for chips.

That is why I wondered if they broached the flutes individually but as you suggest it is deep.

[cal50]

How do you think the flutes were produced then if they weren't broached or forged?

If the stub that you cast is dated 1959 I guess that it would be in the era of "spark erosion technology" but I don't know how good the process would be in this application, i.e. a gun chamber.

---------- Post added at 01:26 AM ---------- Previous post was at 01:17 AM ----------



That is why I wondered if they broached the flutes individually but as you suggest it is deep.

The sharp edges appear to be cut , like broaching but the end angles into the chamber would be almost impossibly cut at the sharp angle.

If I had a spare barrel to keep I would prefer to section it and have a closer look.
It might be an insert not visible externally.

Some M60 barrels used a hardened insert for wear.
Maybe its something similar , I have no idea.