6 arc brass growing belts

[supercorndogs]

I have some Starline 6.5 grendel brass I made into 6 ARC brass. After two loads I see belts forming at the base of a few of them. Does Starline brass have a short web like Lapua? Or could this be an indication the chamfer or counter bore on the chamber is to deep?

 

[Rocketvapor]

Borescope?

 

[6.5SH]

I have some Starline 6.5 grendel brass I made into 6 ARC brass. After two loads I see belts forming at the base of a few of them. Does Starline brass have a short web like Lapua? Or could this be an indication the chamfer or counter bore on the chamber is to deep?

Yes and maybe.

Grendel-like Belted Magnum Problem

I have been shooting a 6mm ARC on and off for the past year or so. I profiled and chambered the barrel (22” Wilson w/rifle length gas), installed the extension and threaded the muzzle. The rest of the parts are reasonable quality parts and appropriate to the build. MUR Vltor upper and lower...

www.snipershide.com

 

[supercorndogs]

Borescope?

What would I do with it?

 

[bcrich]

Aw dam I was just about to order starline 6.5 grendel brass to form into 6arc & was wondering about this very issue is it preventing the brass from chambering ?

 

[supercorndogs]

Aw dam I was just about to order starline 6.5 grendel brass to form into 6arc & was wondering about this very issue is it preventing the brass from chambering ?

I don't think i would get worried about it. Looking at the other thread ledzep says Starline has a taller web so I am sure it does.

Looking at my brass the belt in more like .140 line instead of the .2 line. So I am actually wondering about sizing die after reading the other thread. I had a small base 264 LBC die that did about the same thing now that I have had some time so sit and think it through more and measure some stuff.

 

[Rocketvapor]

You could see case wall shape at the web.
A pin can be used to measure web thickness. I made an aluminum one with a dent in the end for any flash hole protrusion.