I have nearly finished the 6mm AR15 rifle based on a Davidson Defense upper. I have a Vortex Strike Eagle for this one. But now, the hard part. 6mm Arc ammo is about as scarce as a hen's teeth. So I bought the tools to convert some of my Grendel cases to 6mm Arc. The process doesn't sound too complex, but apparently, the case neck ends up too long after the reforming. So I bought the Lee trimmer and die to get that job done. I think the Grendel cases I have take a small rifle primer, and I have plenty of 6mm bullets, so I have to get busy this weekend knocking a few out so I can take this rifle to the range soon. There are loads on the web to use as a starting point depending on my bullet selection.
6mm Arc
- Thread starter kamml
- Start date
backyardtndeer
Well-Known Member
Brass conversion isn't too bad. I have used lapua and starline. Watch for starline to run backorders on grendel brass, if you need brass. I have not run much through the one I built yet. Mostly 100 grain interlocks with imr4895 and accurate 2520.
I started the reloading process yesterday when I pushed two 6.5 Grendel cases through my 6mm arc die. It was easy, but I am still have problems with shortening the case necks. I tried my latest power tool for neck shortening, naw it wan't any good and ruined the resized cases. I will try again soon using my trusty Lyman case turning tool. I have a 243 neck sizer to mount on the cutting head to size the neck and cut the neck shorter. I am confident it will work where I could not get the other tool to work due to my unfamiliarity with the it. Its fun, and I am confident resizing will go well once I have my process down. I have four bullet weights to try, 103, 105,106 & 110. And 4 different powders, Lever Rev, Black, Varget, & Tac.
That's why I went Grendel instead of 6ARC. Still have the itch for the arc though. Just not wanting the additional steps for the brass. Even grendel brass is pretty dang hard to find reasonable. Starline is only occasionally on back order.
I started trimming the 6.5 Grendel brass Sunday to an OAL of 1.490." Using the Lyman shell trimmer is easier than using the power tool device. I tried the 6.5 Grendel several years ago, along with the 6.8 SPC II. I am thinking back to 2002 or 03. I bought a Grendel upper from Alexander since the clones had not come to market yet. His concept was exciting at the time. I also purchased 6.8 SPC I and II uppers, but they were similar efforts based on what I read on the AR16 web page. I even bought .458 Socom brass thinking I would buy that upper for a hog rifle. But since my ARs always outweigh my Marlin 35 Rem, I never used them for hunting and soon lost interest in the AR and its alternative rounds. I built this 6MM ARC just for fun, I am intrigued by its ballistics. And it will get me back to reloading, something I have neglected for several years.
I see where the Army has finally settled on a 6.8 round with very high chamber pressure, 80,000. I think I will pass on that one.
I see where the Army has finally settled on a 6.8 round with very high chamber pressure, 80,000. I think I will pass on that one.
backyardtndeer
Well-Known Member
I just use my hornady case trimmer with the powered case prep tool. May not be as fast as cutting them, but does a good job.
