Panther G Barrel Preparation

[Malcolm.Plumb]

Hi Guys

I have just started the preparation for the build up of the gun barrel and have a couple of questions.

At the join of the two main barrel parts, does the very slight raised lip need to be removed?

Can't seem to find a valid photo as to whether it should be there or not.

Also when it comes to the 111mm measurement from one end to fix the barrel ring.

There is another machined raised ring at this distance which when the ring is butted against it puts this measurement out slightly.
Any problem with this or has this got to be adjusted?

Thanks