Which insert for Hornady case comparator and headspace comparator for 6mm Creedmoor?

[dgheriani]

As I don't see any listed on Hornady's website, I'm curious as to which case comparator would fit in a 6mm Creedmoor (I don't feel like drilling and tapping a case) to measure what OAL is at the lands? Also, which insert would I use to measure the case to see how much they grow and to accurately bump them back 2 thou? The same as I use for .308? Is the datum line on the shoulder at the same diameter? Thanks for any help!

 

[Rob01]

Headspace would be the same one for the 6.5 Creedmoor which is the D .400 but the C .375 would work also. I use the D.

For the OAL gauge, they make one but you would have to find it in stock. You could always neck down a 6.5 Creedmoor modified case.

https://www.midwayusa.com/product/1...rall-length-gauge-modified-case-6mm-creedmoor

 

[dgheriani]

Thanks Rob! I hadn't thought of just necking down a 6.5 one, not sure why since I'll be doing that with a bunch of Hornady 6.5 brass anyways, haha. If the urge strikes me, do you by any chance know what size tap to thread the back of the case to work with the OAL gauge?

 

[Rob01]

No sorry I don't know the tap size. If you can't find a Hornady version Copper Creek offers one although it's a little more expensive.

http://coppercreekammo.com/product/copper-creek-modified-case/

 

[dgheriani]

Thanks again Rob. I just ordered the 6.5 one and I'll neck it down. I was reading another thread and saw that you were using a .270 bushing with Hornady brass for 6mm Creedmoor, did that work out well for you? I have a .269 and .270 (they were out of .271) on the way (as well as a Redding Type-S FL bushing die). I'll be starting with 100 pieces of Hornady 6mm Creed brass and then necking down a few hundred pieces of once fired Hornady 6.5 brass.

 

[Rob01]

Yup the .270 worked just fine. Try it and the .269 and see which works best for you but the .270 should work for you. That said the OAL gauge piece should be looser as you need the bullet to slide easily.

 

[dgheriani]

Yup the .270 worked just fine. Try it and the .269 and see which works best for you but the .270 should work for you. That said the OAL gauge piece should be looser as you need the bullet to slide easily.

I actually meant to ask how those size of bushings worked for sizing your brass, I wasn't really thinking about how I needed the OAL gauge to be looser. I guess I'll have to resize the gauge down to 6mm with a bushing in the die then pass it back through without so that the expander ball will open it up a bit?

 

[Rob01]

The expander might open it back up but you can play with the 6.5 expander too and just try to send it in just enough to open it up so the bullet slides freely.

 

[uscbigdawg]

The tap is a 5/16-36 tap, a particularly difficult one to find. There is an article on Accurateshooter.com that talks about it. I attempted to order it from Amazon, but they lost it in transit. Ended up going to Drills and Cutters (or something like that) and it showed up in a couple of days. Had Owens Armory make one in 223AI and 308, while I was there dropping off my 6CM build, using fired cases from my respective chambers. Left them my tap so that others may benefit and of course to get a 6CM made when I pick up the new stick.