6.5 Grendal vs 6ARC Brass

[Bassfish1952]

If I loaded resized brass do I start over when I move to 6arc brass ?

[corpsman8483]

Not sure what you're asking, but I used some 6.5 Grendel brass that I resized to 6 ARC and had a little problem getting the shoulder just right in order to chamber in my rifle. I have since gotten a bag of starline 6 ARC Brass and it's much better than resized 6.5 Grendel.
Over my Garmin Chromograph, the resized Grendel brass really messes up my SD readings.

[Bassfish1952]

Not sure what you're asking, but I used some 6.5 Grendel brass that I resized to 6 ARC and had a little problem getting the shoulder just right in order to chamber in my rifle. I have since gotten a bag of starline 6 ARC Brass and it's much better than resized 6.5 Grendel.
Over my Garmin Chromograph, the resized Grendel brass really messes up my SD readings.

When I first started reloading for 6arc all that was out there was 6.5 Grendel so I bought some and resized it . Now I have it and lots of 6arc brass so do I need to do a new work up for the 6arc brass or will my loads ( amount of powder ) I used in 6.5 work ?

[CZ527 Guy]

If you had a accuracy node w the 6.5 Grendel fire formed brass, the load may be a bit diffrent with the proper 6mm ARC head stamp brass. Though I doubt you will see much if any difference.

[Old Bob]

Case capacities may be different from resized & fire-formed 6.5 Grendel brass & your new 6 mm ARC Brass. Weigh your cases to see if there is a noticeable difference. If there is a difference, restart your load work-ups for the new 6 mm ARC brass.

What brands are the two different cases?

[grayfox]

"When I first started reloading for 6arc all that was out there was 6.5 Grendel so I bought some and resized it . Now I have it and lots of 6arc brass so do I need to do a new work up for the 6arc brass or will my loads ( amount of powder ) I used in 6.5 work ?"

Bass, they are probably close, but at first you should treat them as a new "headstamp"/brand... take a known good load in the 6Arc brass (not right at max), and load 3-4 into the reformed 65 brass. Load and shoot them 1 at a time in your gun, check the MV, grouping and brass condition. If there is any delta that's how you can find it.

[StoneHendge]

Was your resized Grendel brass Starline? If so, you should be very close with the Starline ARC brass - they are made from the same parent blank (Grendel Basic Brass), but you may need to tweak powder a few tenths. If not, you should work it back up again. Starline's Grendel case capacity is different from Hornady, Lapua, etc.

[Bassfish1952]

Case capacities may be different from resized & fire-formed 6.5 Grendel brass & your new 6 mm ARC Brass. Weigh your cases to see if there is a noticeable difference. If there is a difference, restart your load work-ups for the new 6 mm ARC brass.

What brands are the two different cases?

Both are Starline

[corpsman8483]

I had weight differences, quit using resized Grendel brass and only use Starline 6ARC brass now. Seems that when I resized the 6.5 Grendel and trimmed to length I had necks that were a little thicker (>0.001") and that affected neck tension and it's ability to chamber.