Barrel Tooling mark ?

[Buckshot]

Hi Guys and Gals I have just joined the QB78 family and I am loving it. I am preparing to do a good cleaning and deburring once a get the O-ring kits in but in going over the air gun I noticed this mark in the barrel I did some more crowning to see if I could "reach it" but could not. Do I need to file the end of the barrel down and recrown ? Can it be done with simple tool eg. flat file or grinder ? Or is it nothing to worry about?

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New Air rifle needs a good cleaning LOL.
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[Gippeto]

Clean up the rifle and shoot it before working the crown further. It'll tell you if it needs more work. ;)

Al

[SeanMP]

Yup all the QB's/AR's have that little tooling mark just inside the crown. As Al says you can just shoot it and it should be mostly okay.

I'm a barrel fanatic so I get rid of the first 3/16" as a matter of normal practice. But then I do all kinds of other crazy laborious stuff as well to squeeze every bit of accuracy out of a barrel.

If you have a belt sander with a side disc platter or a good bench grinder you can set yourself with a side platform that is as close to 90deg to the X/Y axis as you can manage. if your platform is 24" long seeing a 1/4deg is possible. Add a couple strips of wood to the platform cut at a 45deg edge to form a V block. Then your in the barrel grinding business.

The key is keep the barrel rotating constantly and keep it cool by plunging it in cool water every 30 seconds of grinding.

Building the jig accurately is going to be more important than the actual process of grinding the barrel.

Once you have your grinding done use the usual brass screw method for cutting the final crown. But if your looking for absolute accuracy don't go wild. Only enough to see a clear line that shows the lands and grooves

[Buckshot]

Thanks guys I quess I'm jumping the gun a bit LOL. I'll give her a good cleaning and go from there.

Richard