Scratches and marks in AR chambers..... What is excessive and what is OK?

[41bear]

On a related note, in my issues with Faxon's nitriding vendor (now fired) leaving residue in the chamber and having to polish it out, they recommend spinning a ball hone in the chamber for about a minute and 30 seconds.

See attached photos for the model used for Grendel chambers. Costs about $20 directly from Brush Research Manufacturing (BRM) with $10 shipping for $30 total.

See VIDEO HERE on how to use it.

I've used this on 2 barrels, the 12.7 GB and the el cheapo Anderson, it works great. An nice addition to the AR tool box just go slow and check often.