So I went ahead and resized 50 pieces of 6.5 Grendel brass to 6mm ARC yesterday and noticed today some marks along the top of the neck and one around the center of the brass this morning.  I think the 2 lines at the top of the neck are what are referred to as "vampire marks" from the feed ramps?

   

I'm not sure what may be causing the ring around the center of the brass.

   

I tried rubbing the ring around the center of the brass but it doesn't seem to have had any affect.

The last thing I did yesterday was to chamber them and closed the bolt to make sure they would fit.  I think this is where the marks occurred but cannot say for sure.  Any ideas?  Should I be concerned with either of these marks?

https://lanbosarmory.com/index.php?main_...a&oos=hide

About 12 bucks with 10 buck flat rate shipping

Finally located 6mm ARC ammo locally They had all 3 varieties in stock at Runnings. Two box limit and had been on the shelf for a while or so I was told. 105 & 108 grain was priced near $25.00 per box. 103 gr ELDX was too much for my blood at $41.00 ish per box.

Selected 2 boxes each of the 105 & 108's So looks like I have ammo to work with and reload when my barrel arrives for the CZ 527. Sounds like the barrel may still be a month out or so

Starline 6.5 Grendel Brass stocked at 
https://www.armorally.com/shop/starline-...del-brass/

not crazy about the price - but they have them in stock.

Brief background first...
I'm from the communist territory of NY originally and moved to Louisiana
Discovered I could easily buy firearms
Bought firearms 
Started shooting USPSA about 5 years ago
I let my pistol primer stash get low and hit the rifle primer lottery a few times....

  Present time....ran across a 20" Monster barrel a few weeks back and had a lonely Aero M4E1 Enhanced receiver set laying around so everyone here knows what had to be done. I was interested in the cartridge from launch but wanted to be sure it wasn't another Valkyrie first. I'm fairly certain it's here to stay and it's the real deal. I never shot past 100yds before nevermind zero a scope. I tend to research stuff to death and overanalyze everything...I don't know, it's subconscious, but helps me sometimes. 

   I'll get some pics when I get a chance but it's nothing spectacular currently, still waiting on some backordered items still in a production run. My entry rig to PRS/NRL type events before dropping big coin on a chassis. I did a rough sight in  and tracking test at 50yds and took her to 100yds. Had a rough time with first extraction problems then feeding issues. Big dummy forgot to open my SA adjustable block....at all!      LOL      Still think its not lined up right and have it too far back from muzzle to the shoulder. I'm new to the AR platform but have built a few and nailed it in the past. Short Blackouts with pistol gas, maybe the ports are bigger and less fussy? I'll have to feeler gauge it like I should have.

   Anyways, after a hasty, and I mean hasty 1.5MOA zero at 100 I dialed in for the 600 yd steel. This is what amazed me about the 6ARC....18mph gusty/switching wind 90 degrees to shooting azimuth, 24' elevation, 82 degrees and 70% humidity, only 4.1mil elevation and 0.4mil windage.....not ideal atmospherics for the new guy I imagine, and it was within 1 foot POA-POI with no chrono data and a noob driving! I meant to feed geoballistics 2625 velocity but put 2725 and it hit low for what ever reason. I didn't range the target but I was impressed as you can tell I'm sure.

    So quick question, am I on the right track with the gas block being too far back and undergassed? (Brass ejecting between 3 and 4 with authority just not feeding next round at all or jamming on ramps, regular carbine buffer, 108 ELD Match factory loads.)
****HMMMMM, need to figure out HOW to post pics now...lol****

Does anyone know the gas port size for the Faxon Gunner 12” barrel for the 6 ARC?

Gentlemen, the armament elves at SIXFIVE have not been sleeping.

We're pleased to announce that our new MONSTER ULTRALITE GAS BLOCK is now in manufacturing and will be ready for sale in early August.

It will be a low-profile, clamp-on style, fitting .750 gas journals, with ultra-lite lightening cutouts, and the screw heads will be shrouded within the block to preserve a sleek appearance and so that they don't contact the inner diameter of your handguard. Value-priced as always.

I prefer clamp-on models over set-screw models because, even though a set screw is the cheap and easy way to do it, I think a clamp-on provides both a tight gas seal and a tighter overall attachment. If you think about how a set-screw gas block works, as you tighten the screws on the bottom, the top of the gas block is pulled down onto the gas port hole — so far, so good — but the rest of the gas block is actually pushed AWAY from contact with the barrel; and this is exacerbated if there is any tolerance mismatch between the barrel's gas block journal and the hole drilled in the set-screw gas block. A clamp-on version avoids this, and gives us a best-of-both-worlds proposition, providing even contact around the circumference of the barrel. (The bottom of the barrel will also not be marred by the set screws, should you want to resell the barrel.) Having said that, the differences in practice between clamp-on and set-screw models are small and it comes down more to personal preference.

Bottom line: The MONSTER Ultralite Gas Block — like James Bond — does the job well, and does it in style. 

See attached 3D CAD drawing.


   

We are adding to our three-prong Alpha flash suppressor model a Bravo version for those who requested a closed-end muzzle device.

The MONSTER Ultralite Alpha has sold out and a new batch is in production, along with the brand new Ultralite Bravo.

These are designed to have a sleek, modern look with a small diameter of just 0.740, which mates perfectly with a MONSTER barrel in either 6mm ARC or 6.5 Grendel. This allows a gas block to slide over the muzzle device without needing to remove it, and also keeps the weight down. These weigh less than a standard A2 but are much, much more effective.

See attached 3D CAD drawing.

   

Due to Bergers now being cheaper than a lot of Nosler & Sierra oproducts I ordered some 64gr Column proj to try in my Howa mini.   I put the mini back into the old Howa Kryptek stock with a some fresh bedding in the knox area to stiffen the stock and improve accuracy.......

I had just run out of 8208 so a quick look on burn rates chart showed the closest powder I had on hand was Re10X ( in between H322 and H335) which are mention in Hornadys data for 65gr Vmax's.

I started a bit on the low side at 27gr and stopped at 29gr, there is still a bit of space left in the case and I suspect Im probably around 1.5gr off top load....

6mm ARC brass, Rem 7.5, 1.485, RE10x, Berger 64gr, 2.100.

Charge   Velocity

27.0       3082     3075     3081     3098     3063
27.5       3080     3118     3119     3135     3113
28.0       3129     3184     3173     3163     3178
28.4       3215     3224     3198     3234     3255
28.7       3251     3277     3271     3263     3271
29.0       3274     3297     3276     3291     3305

ealry accuracy in the first 3 groups then things went a little all over the place,  hoping there is a higher node above 29.0gr other wise I'll play around with the 27.5gr load.  Next session Ill throw the mini back into the chassis.

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Hello everyone I new to the site and hoping to get and exchange notes on reloading the massive 6ARC.