New 6mm Advanced Rifle Cartridge

Did yours shoot well right from the get-go?

Forgot to mention I’m shooting factory hornaday 108 and 105.
For reference - a couple OCWs with 105 Bergers over Varget and 58 VMax over xbr8208. 18" proof Carbon. Shoot well under moa with both 105 and 108 factory loads as well. My 12.5" Faxon prints into 1.5" with 105s and 2" with 108s at 100 for 10 shot groups. My barrel started to group consistently at about 50 rounds down the tube.

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Did yours shoot well right from the get-go?

Forgot to mention I’m shooting factory hornaday 108 and 105.
...that particular group was the max Berger 95 VLD load and the 67th, 68th & 69th round of 113 rounds down a brand new BA 18" barrel. It was the 1st time out for the build. I have not been able to get any factory ammo so I went straight to handloads. I only use factory ammo to validate a build and establish baseline data. If you scroll back in this thread my results from that day are posted. The focus was testing powder charges for pressure, not accuracy, ensuring the bullet passes over the optical sensors of my old chrony, having an aiming point down range helps to keep that bullet as centered as possible over the sensors. Pic I took waiting for the rain to pass, had to bring chrony under the canopy.

I know alot of folks post disparaging comments about BA barrels, but I've been using them for over 10 years (300BLK, 223 Wylde, 556, .308 & 6.5CM) and haven't had a bad one yet. As for your experience, before returning it I'd suggest put enough rounds thru it to "break in" before returning under their MOA warranty guarantee. I would also complete break in before making any changes to establish a good baseline. FWIW, I only torque my barrel nuts to 35 lbs and I also face all of my receivers. I do have extra receivers and I'll match the barrel to whichever receiver has the tightest fit. Haven't had the need to go with shimming or gluing/bedding yet.

In building, patience is your friend.... if you want immediate accuracy results, maybe buying a factory built reputable brand of rifle (and its recommended ammo) specific to accuracy might be less frustrating for you.

Good luck in your future endeavor with 6ARC.
 

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....JKGTR, here are some pics of MY test results out my BA 10.1" Hanson in 300BLK and 16" Hanson in .308 barrels. It is results like these why I keep using BA barrels... I feel I get my bang for the buck, simple as that.
 

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Well I’m a believer in X-Caliber now. This is my first X-Caliber barrel. I couldn't resist the nice weather so I hit the range a few days ago and did a 20 round break in (doing the shoot and clean method) and then shot four 5 rounds groups. All groups were shot from a bench and using an Atlas CAL bipod and rear bag. The range I was shooting at doesn’t permit shooting from prone, otherwise I would have shot prone. The early results look promising and make me think it's a shooter! For factory loaded ammo at 100 yards, I'd say it's going to be tough to duplicate this through hand loads. The point of impact for each of the four groups changes because I was dialing in the scope zero. Hopefully I gain consistency in muzzle velocity by hand loading. I'm very pleased.

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Well I’m a believer in X-Caliber now. This is my first X-Caliber barrel. I couldn't resist the nice weather so I hit the range a few days ago and did a 20 round break in (doing the shoot and clean method) and then shot four 5 rounds groups. All groups were shot from a bench and using an Atlas CAL bipod and rear bag. The range I was shooting at doesn’t permit shooting from prone, otherwise I would have shot prone. The early results look promising and make me think it's a shooter! For factory loaded ammo at 100 yards, I'd say it's going to be tough to duplicate this through hand loads. The point of impact for The point of impact for each of the four groups changes because I was dialing in the scope zero. Hopefully I gain consistency in muzzle velocity by hand loading. I'm very pleased.

View attachment 7819305View attachment 7819308View attachment 7819309
Those groups look solid. What was the lead time from order until received?
 
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Stevieb92, I remember following your journey w/6.5CM using a BalAdv barrel, lots of good info and results in that series. I have considered XCaliber tubes before, but just seems like every time I wanted to try one, they were OOS or very long lead times. They are on my list of tube makers, and it really comes down to who has what I desire, when I want it and if it fits in my budget.
 
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Well I’m a believer in X-Caliber now. This is my first X-Caliber barrel. I couldn't resist the nice weather so I hit the range a few days ago and did a 20 round break in (doing the shoot and clean method) and then shot four 5 rounds groups. All groups were shot from a bench and using an Atlas CAL bipod and rear bag. The range I was shooting at doesn’t permit shooting from prone, otherwise I would have shot prone. The early results look promising and make me think it's a shooter! For factory loaded ammo at 100 yards, I'd say it's going to be tough to duplicate this through hand loads. The point of impact for each of the four groups changes because I was dialing in the scope zero. Hopefully I gain consistency in muzzle velocity by hand loading. I'm very pleased.

Very nice. I was looking at X calibers website. Lots of options available. What are your specs?
 
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Stevieb92, I remember following your journey w/6.5CM using a BalAdv barrel, lots of good info and results in that series. I have considered XCaliber tubes before, but just seems like every time I wanted to try one, they were OOS or very long lead times. They are on my list of tube makers, and it really comes down to who has what I desire, when I want it and if it fits in my budget.
Thanks for the kind words. Yes, that series on the 6.5CM BA barrel was fun and turned out some nice results for a relatively cheap barrel that a lot of people frown upon, but I was happy with mine. I special ordered this 6mm ARC barrel and was quoted a 12-14 week lead time. They delivered it in about 6-7 weeks. I was able to take advantage of their sale, I believe it was 20 percent off, which brought it in around 280 bucks. I also ordered a LR-308 barrel at the same time and both were delivered together. That build is coming in the next couple months.
 
Very nice. I was looking at X calibers website. Lots of options available. What are your specs?
Thanks. Yes, it is truly customizable. I went with a 20 inch, stainless steel, 1:7 twist 5R rifling, bull contour, rifle length gas and standard length gas journal and 5/8-24 threads. The specs are also shown on the card in the second pic in my post. No other options.
 
Thanks. Yes, it is truly customizable. I went with a 20 inch, stainless steel, 1:7 twist 5R rifling, bull contour, rifle length gas and standard length gas journal and 5/8-24 threads. The specs are also shown on the card in the second pic in my post. No other options.
Ah, ok. I did not notice, my apology.

Interesting twist for the hornaday ammo. From what I’ve heard, no less than 7.5” twist rate should be used for that ammo. However yours seems to be shooting nicely. 👌🏼
 
I want to stick with the heavy 100+ bullets for this rifle, so I selected the faster 1:7 twist. My understanding is if a lighter bullet is desired to be used a slower (1:8) twist rate can be used. As far as the 108 ELD-M bullet, I believe Hornady recommends the 1:7.5 (or faster e.g. 1:7) twist rate. I'm very pleased with my results so far.
 
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I just made ~200 more rounds last night. Starline Basic Straight wall converted w/ Hornady 100gn BTSP. These will be plinkers and are primarily for fire forming. I used LeverEvoloution, but forgot/wished I had used the ppVarmit that I have on hand and save the LL for the Bergers.
 
....came across a post on another forum about a person relating how his gas tube (rifle +1, IIRC) became clogged up after ~1000 rds fired, a combo of Hornady factory & Lever handloads. He replaced the gas tube to get it functioning again. The individual competes in PRS type events, hence his high round count in fairly consecutive sessions. I found it interesting as my extremely limited experience with LVR so far indicated it is a "dirty" powder. It's something I'll be watching for as I expend more rounds, just in case...
 
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About two weeks ago Brownells got some Hornady black 105 bthp ammo in stock so I ordered a case. Mainly for the brass. I shot 3 5-shot groups of that and 3 5-shot groups of the Hornady 108 ELD-M to compare. The groups were shot in this order; 1, 4, 2, 5, 3, 6 to mix it up and try and randomize it. The two worst groups were definitely my fault. I need to get better at building a solid shooting position. Over all 6 of the groups it shot roughly 3/4 moa. I can’t complain about that for factory ammo.
 
stevieb92,

Nice shooting.

I’ve been pleasantly surprised with the factory stuff also. (Well, the groups from the TAP load are mediocre, but that bullet is made more for great terminal performance and not tight groups.)

If you get a chance to try some of the ELD-X loads it might be worth a go. I’ve found the -X to group as well as the -M and Black. Not too shabby for a hunting bullet!
 
I've been sorta following this thread, but not real close has there been much discussion on AR mags?

I'm using 10 rd PRIs with good success, how about everyone else? I've also got some 5 rd ASCs that suck. I think they're the same body as 10 rounders but the spring is different.
 
Best results I've seen are with E-lander 15/17 rounders. The 25's work well, too, provided you keep them reasonably clean and/or lubed. The soot buildup from shooting suppressed can gum them up (bolt starts outrunning the mag). Unsuppressed no problems.

ASC 15 rounders have also held up reasonably well, but I've had one that gave me some fits and I tossed it.
 
I've been sorta following this thread, but not real close has there been much discussion on AR mags?

I'm using 10 rd PRIs with good success, how about everyone else? I've also got some 5 rd ASCs that suck. I think they're the same body as 10 rounders but the spring is different.
Are you using the 6.8 PRI mags?
I am continuing to have feed issues. Anybody tried the new Geissele mags?
Not thrilled with the idea of $50 mags, but I am getting frustrated and need to find a solution.
 
Are you using the 6.8 PRI mags?
I am continuing to have feed issues. Anybody tried the new Geissele mags?
Not thrilled with the idea of $50 mags, but I am getting frustrated and need to find a solution.
Yes. I think they're 10 round 6.8 mags. I only load them to 5 for the 6mm. I also did a fair bit of mag lip tweaking and sanding/polishing.

I looked at those geisseles but they looks pike a direct copy of the ASCs so I can't bring myself to buy them.
 
Looks like those brentons are just rebranded. Elanders maybe? Not that that's a bad thing, just curious.
I don’t think there are. Brenton has pushed the width to the max which is what the Grendel case needs. My PRI 6.8’s don’t work very well cause they’re to narrow inside.

Here is a pic of the bottom plate& follower on the Brenton’s
image.jpg
image.jpg


I don’t have any elanders to compare so let me know?
 
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I don’t think there are. Brenton has pushed the width to the max which is what the Grendel case needs. My PRI 6.8’s don’t work very well cause they’re to narrow inside.

Here is a pic of the bottom plate& follower on the Brenton’sView attachment 7827629View attachment 7827630

I don’t have any elanders to compare so let me know?
p_100026279_1__79186.1564438859.jpg


This is an elander. Looks the same too me. Like I said, not always a problem, but the elander is like half the price. Or less.

My biggest concern is getting a couple mags in the 15ish round range. I actually prefer the 10s for this gun, but WA has a high cap mag ban going into effect in July so I want to get a couple larger ones.
 
View attachment 7828014

This is an elander. Looks the same too me. Like I said, not always a problem, but the elander is like half the price. Or less.

My biggest concern is getting a couple mags in the 15ish round range. I actually prefer the 10s for this gun, but WA has a high cap mag ban going into effect in July so I want to get a couple larger ones.
We already have the mag ban bullshit here in MD.
Brenton ships these 15 rd mags blocked to 5 rounds for hunting so they can be shipped here. Block is easily removed.

They aren't cheap, but again based on that e-lander pic above, the Brenton's are not the same.

Compare the mag catch window shape & the indented stiffening ribs adjacent to the window. Brenton's ribs are much shallower. This is what gives Brenton's wider inside dimension for the Grendel case. Also notice the 2 stiffening ribs on the Brenton get deeper right below the feed lips.

Small details matter more with Grendel sized cases.

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ASC OEM then it looks like.

The reason I like the PRIs is because they allow a little bit longer loads. They are spendy though. I may just have to bite the bullet and buy one of everything in the 15/17/20 rd realm and see what works best.
 
Just sharing a cool 6ARC video:

I made another 70 plinkers the other day with Starline Blank headstamps and 100gn Hornady BTSP. Mostly to finish off the last little bit of ppVarmit I had left. All my ARC powder is now LeverEvolution now for ease of loading. sticking with 105s here on out.
 
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Just sharing a cool 6ARC video:

I made another 70 plinkers the other day with Starline Blank headstamps and 100gn Hornady BTSP. Mostly to finish off the last little bit of ppVarmit I had left. All my ARC powder is now LeverEvolution now for ease of loading. sticking with 105s here on out.

I saw that yesterday. Makes me wish I’d have saved my money on this build and just ordered one of those.
 
i just finished up my 6 arc build for hunting coyote. worked up a nice load using 70 gr nosler varmageddons.
32.6 gr cfe223.
average velocity - 3020 FPS
ES-11 SD-5
20" cmmg 1:7.5 barrel
vg6 brake
shooting sub MOA @100 yards. i'll upload pics tomorrow of my rifle setup and grouping.

all in all im happy with the round. only using CFE223 cause thats what i happened to have on hand and Lever powder was no where to be found.
 
i just finished up my 6 arc build for hunting coyote. worked up a nice load using 70 gr nosler varmageddons.
32.6 gr cfe223.
average velocity - 3020 FPS
ES-11 SD-5
20" cmmg 1:7.5 barrel
vg6 brake
shooting sub MOA @100 yards. i'll upload pics tomorrow of my rifle setup and grouping.

all in all im happy with the round. only using CFE223 cause thats what i happened to have on hand and Lever powder was no where to be found.
What rifling do they use in that barrel?
 
My biggest concern is getting a couple mags in the 15ish round range. I actually prefer the 10s for this gun, but WA has a high cap mag ban going into effect in July so I want to get a couple larger ones.


I'm in the same boat as you trying to beat the july deadline. So when I did my last order through lanbosarmory I snagged a few of the 20rd duramags just to have on hand, hopefully they'll work...
 
Are you using the 6.8 PRI mags?
I am continuing to have feed issues. Anybody tried the new Geissele mags?
Not thrilled with the idea of $50 mags, but I am getting frustrated and need to find a solution.
I just ordered some Geissele 15 and 25 rd mags from Brownell's. I believe this is the first time they have became available anywhere. They have a stainless steel body and are black oxide coated, and have their 6mm ARC tweaked followers.

AR-15 6MM ARC MAGAZINE STEEL
 
I just ordered some Geissele 15 and 25 rd mags from Brownell's. I believe this is the first time they have became available anywhere. They have a stainless steel body and are black oxide coated, and have their 6mm ARC tweaked followers.

AR-15 6MM ARC MAGAZINE STEEL

I want to know if these are a rebranded product like their last overpriced magazine…

Brownells has had them up for maybe two-ish weeks, but at the cost I’m hoping someone else will do the research for me.
 
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I want to know if these are a rebranded product like their last overpriced magazine…

Brownells has had them up for maybe two-ish weeks, but at the cost I’m hoping someone else will do the research for me.

I guess maybe give Geissele a call about them. Below is a link to a vid from SHOT 2022 on the Geissle 6mm ARC rifle. They say *they* redesigned the mag and follower along with *their* new barrel extension for the 6MM ARC. I am in for one of their 6mm ARC uppers when they become available.

New Geissele GFR 6mm arc Shot Show 2022

New Sniper Support Rifle & New Advanced Rifle Cartridge


Geissele Automatics - 6MM ARC Geissele Fighting Rifle Is Here! - SHOT Show 2022
 
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I would think that they have maybe messed with spring rates or followers or something, but that's a C products/duramag or elander body.

Let us know how they work. I've been stuffing my 6mm Grendel variant into 6.8 mags but im gonna have to try some dedicated arc or grendel mags now that theyre more popular.
 
I would think that they have maybe messed with spring rates or followers or something, but that's a C products/duramag or elander body.

Let us know how they work. I've been stuffing my 6mm Grendel variant into 6.8 mags but im gonna have to try some dedicated arc or grendel mags now that theyre more popular.

They look like ASC magazines. Same 410 Stainless Steel Body. https://www.ammosc.com/categories/ar...s/6mm-arc.html

I emailed Geissele to see what they have to say about it. If they manufacture the mag bodies and followers in house or not. That's one reason I get and try a lot of gun stuff from Brownell's if the price is comparable. Because you have 45 days to get a full refund, other than the shipping cost back to them. Also, Geissele says they are using their own extended feed ramp barrel extensions for the 6mm ARC cartridge.

https://www.brownells.com/helpcenter...ndex.htm?id=57
 
They look like ASC magazines. Same 410 Stainless Steel Body. https://www.ammosc.com/categories/ar...s/6mm-arc.html

I emailed Geissele to see what they have to say about it. If they manufacture the mag bodies and followers in house or not. That's one reason I get and try a lot of gun stuff from Brownell's if the price is comparable. Because you have 45 days to get a full refund, other than the shipping cost back to them. Also, Geissele says they are using their own extended feed ramp barrel extensions for the 6mm ARC cartridge.

https://www.brownells.com/helpcenter...ndex.htm?id=57

The discussion from SHOT is why I had my eye out for these, but the price turned me off until these can get out in the wild for testing. I have Duramag in the meantime.