Where is 6arc going?

Would the Titan be only for bolt action rifles? Do they make one for the AR-15 ?

EDIT -- Didn't see the variety of bolts until I opened my laptop, sorry. Question: Then which of the two on the right would be best for the 6 ARC? And what might the difference be between them? And thanks for offering this info up.
The one on the far right is the 800 series and even though I was making them in 2007, a guy (Kramer) filed for and received a patent in 2015. He threatened to sue me if I made any more, no Kramer has never made a single bolt. I could have gone to court but at $500 an hour it wasn't worth it.
The 750XD second from right is .750 Dia so it could be made and not infringe on Kramer's fake patent. The Titan just has a little better tolerances and is plenty strong enough for Grendle and ARC sized cartridges limited to 55000 psi. I explained more in the PM. I retired in 2017 and no longer make any of those big bolts.
 
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The one on the far right is the 800 series and even though I was making them in 2007, a guy (Kramer) filed for and received a patent in 2015. He threatened to sue me if I made any more, no Kramer has never made a single bolt. I could have gone to court but at $500 an hour it wasn't worth it.
The 750XD second from right is .750 Dia so it could be made and not infringe on Kramer's fake patent. The Titan just has a little better tolerances and is plenty strong enough for Grendle and ARC sized cartridges limited to 55000 psi. I explained more in the PM. I retired in 2017 and no longer make any of those big bolts.
Interesting. Very reminiscent of Knight’s E3 bolt.
 
Stronger than your average bolt. The bolt on the far right is the 800 series was designed to allow shooting a 6BRX(308 diameter) in and AR15, it came first around 2007 there were also Grendel and 6.8 versions. The second from the right and second design is the 750XD also works with 308 sized, Grendel, 6.8 sized cartridges. third from the right is the Titan, I designed it for Grendel/7.62x39 sized cartridges, never made those for the 6.8. 2 bolts on the left are 5.56 and 6.8 I believe.
View attachment 7874682

I wish you still sold the Titan.

The ARC is my first Grendal case build. Set it up as a straight comp gun. We have Geissele & IWI gas gun comps up here. Also plan to try it in place of my 6GT for PRS. AR with 22” barrel running Berger 109’s @ 2720 using Lever & formed Lapua or ARC Hornady brass. I’m running the Maxim bolt in the ARC.
So same bullet 200fps slower in the ARC vs GT.

I’m running Brenton 15rd Long Load mags for the ARC.
They have been plug & play, no issues. I tried machining the follower in a 6.8 PRI mag, but the PRI are just to narrow inside for the Grendal case. They bind up over 5 rounds.

The draw for me is simple. I wanted to build a 6 & there really isn’t another non wildcat 6mm small frame option. The 6 should have an advantage at range for spotting hits/misses. Then there was also the empty promise of factory ARC brass. Lots of Barrel options, bolts, dies, & functional mags. Aside from ARC there’s the 24 Nosler. The 24 just doesn’t have enough powder capacity for a 6mm.

The factory Hornady 108’s shoot under 1 moa @2650 so plenty good enough to shoot a comp with. Price on the factory offerings is in full retard mode though. I’ve just been converting 6.5G brass to ARC. LE Wilson FL bushing dies are on point @SAAMI SPEC. It seems there’s been some issues with other dies that are kind of unadvertised small base effectively.
The factory ammo has the smaller base at the .200 line vs Lapua Grendel that is sized to SAAMI.

Honestly I think in a strictly target/ballistic Comparison the ARC & Valk are about even. From a strength standpoint the 6.8 bolt is no doubt stronger, but so far IME the primer pockets in the 6.8 case give up quicker than the Grendel. To be fair the 6.8’s primer pockets are dealing with higher pressure.

I know hand loaders are way down on the list for consideration by the big manufacturers, but man it would be great if someone offered primers in +.002 od.

I just formed a bunch of 24 Nosler brass for the Valkyrie. Just shot the first full loads yesterday from the fire formed brass. Results were very good. My 18” Valk shoots the factory 88 ELD @2508. Pretty anemic. I’m running the LWRC 6.8 lobster tail bolt for the 6.8/Valk.

With the formed 24 Nosler Brass, 5.56 bolt, 88 ELD’s & 27.2gr H4350 I got 2691 & SD 4.2. With 26.1gr Lever 88’s went 2744 SD 11.8. Primer pockets still good on these, we’ll see how long they last.
 
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Honestly do not remember where the mags came from. I know of no new mags for the cartridge. Doesn't mean there arent any. Some of the ones I have are 17rd Israeli made for 300 BO. That said they only fit 11 of the ARC. Pic to follow
The orange tape is how I separate calibers

I have had great experience, so far, with the lancer (white follower) and with the AR Stoner. Midway USA advertises the AR Stoner as 6 ARC, 15 round magazines. There are other capacities too.
 
I have had great experience, so far, with the lancer (white follower) and with the AR Stoner. Midway USA advertises the AR Stoner as 6 ARC, 15 round magazines. There are other capacities too.
Yeah, I bought a bolt, mags and ammo while I waited on my PR cf barrel to be made. Still occasionally buy ammo just bc I’m conditioned to! There just were not many mags being touted as for ARC. Everyone I have met that has one loves it.
 
The one on the far right is the 800 series and even though I was making them in 2007, a guy (Kramer) filed for and received a patent in 2015. He threatened to sue me if I made any more, no Kramer has never made a single bolt. I could have gone to court but at $500 an hour it wasn't worth it.
The 750XD second from right is .750 Dia so it could be made and not infringe on Kramer's fake patent. The Titan just has a little better tolerances and is plenty strong enough for Grendle and ARC sized cartridges limited to 55000 psi. I explained more in the PM. I retired in 2017 and no longer make any of those big bolts.

Is this the same Constructor that was on 6.8 forums and sold some amazing barrels?
 
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I like how the 6ARC performs after the trigger pull but thats about it. I have an ADM lower/Aero upper semi-auto rifle which has decent luck with ASC magazines, it hates E-lander, and CPD. The magazines are in my opinion the 6ARC/6.5Grendel Achilles heel. Every thread has the same stories about how Brand-X Mag works flawlessly but only on Tuesday afternoon if you download it by half capacity or magic-Dremel it to get 50% +5rounds. I would rather someone came up with a cartridge that performs like the 6ARC but better fit the AR-15 magwell to allow for more reliable magazine feeding - I don’t care how they do it or what parent case they base it on. I want to have the same braindead reliability the “put 556 in pmag and shoot it” people enjoy. If someone ever made that cartridge I’d barrel/bolt/magazine change and never look back.

@Constructor I remember reading a ton of your threads and seeing the stuff you were making. Unfortunately I was too late to the party and you’d already moved on.
 
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I like how the 6ARC performs after the trigger pull but thats about it. I have an ADM lower/Aero upper semi-auto rifle which has decent luck with ASC magazines, it hates E-lander, and CPD. The magazines are in my opinion the 6ARC/6.5Grendel Achilles heel. Every thread has the same stories about how Brand-X Mag works flawlessly but only on Tuesday afternoon if you download it by half capacity or magic-Dremel it to get 50% +5rounds. I would rather someone came up with a cartridge that performs like the 6ARC but better fit the AR-15 magwell to allow for more reliable magazine feeding - I don’t care how they do it or what parent case they base it on. I want to have the same braindead reliability the “put 556 in pmag and shoot it” people enjoy. If someone ever made that cartridge I’d barrel/bolt/magazine change and never look back.

@Constructor I remember reading a ton of your threads and seeing the stuff you were making. Unfortunately I was too late to the party and you’d already moved on.
I made a few hundred TAC6 barrels and I still have a few of my own personal. It feeds well especially out of the LWRC SIX8 platform using Pmags. Maybe after I get rid of a million pounds of burden I can get back to doing what I really like to do.
 
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For reloaders, find someone who shoots 6 ARC and doesn't reload. Make a deal with him/her to pick up his brass and buy it from him. Troll the line at the range to see if you can spot someone. Or you can just go buy it.
Poke your head out from under that rock occasionally.
If the 6 man bun ammo or brass were available they would not be on my shit list. DUH
 
I made a few hundred TAC6 barrels and I still have a few of my own personal. It feeds well especially out of the LWRC SIX8 platform using Pmags. Maybe after I get rid of a million pounds of burden I can get back to doing what I really like to do.

You mentioning the TAC6A and SIX8 receivers brings back some memories.

There was a 6.5Grendel forum thread I stumbled into where people were saying the SIX8 Pmags worked at full capacity for 6.5Grendel. I put together a rifle based on the New Frontier Armory C-6.8 receiver set which is SIX8 Pmag compatible using a 6.5 Grendel barrel. Then I learned the internet lies; didn’t work at all much less at full capacity. I looked around trying to figure out what else I could do with a C-6.8 receiver set and 6.8Pmags, thats when I first came across your posts and the TAC6. Ultimately ended up giving away the receiver set to family who wanted to put together a 224 Valkyrie.
 
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Those are E-Lander and the quality on them varies from great to utter crap.

Yep, I bought 10 of the 28rd E-Lander mags when I got my 6.5G upper and was never satisfied with the failures to feed.

I dusted off my old CPD 27-28rd 7.62x39 mags and they've run legit 100% over ~300rds. By no means an exhaustive test, but better than the 1-3 nose up failures to feed per magazine I was getting in the three E-Lander mags I took out of their packaging. I sold all 10 for a loss and just use the 10+ year old CPD x39 mags at this point.

If someone really could make the "PMAG of the 6.5G/6ARC world" they could print money....
 
The Grendel with a .136 recess is weaker than the bolt with the .124 recess 7-8% but still weaker, any engineer can explain that in about 30 seconds. The bolts below are the Titan, quite a bit stronger than the type 1 or 2.
View attachment 7874662
Where can I get one of these?

I’m about to tear apart a KAC barrel for the extension and open up a SR-15e3 bolt to try to run higher pressures.
 
Where can I get one of these?

I’m about to tear apart a KAC barrel for the extension and open up a SR-15e3 bolt to try to run higher pressures.
The only thing left on ARP website is a box of 40-some 7.62x39 barrels + extensions for $2K 😂. The bolt face depth on x39 is incorrect for factory 6mm ARC though.
 
You mentioning the TAC6A and SIX8 receivers brings back some memories.

There was a 6.5Grendel forum thread I stumbled into where people were saying the SIX8 Pmags worked at full capacity for 6.5Grendel. I put together a rifle based on the New Frontier Armory C-6.8 receiver set which is SIX8 Pmag compatible using a 6.5 Grendel barrel. Then I learned the internet lies; didn’t work at all much less at full capacity. I looked around trying to figure out what else I could do with a C-6.8 receiver set and 6.8Pmags, thats when I first came across your posts and the TAC6. Ultimately ended up giving away the receiver set to family who wanted to put together a 224 Valkyrie.
You are right, I tried Grendel cartridges in the LWRC mags when they first came out and found that they bulged to the point the mag would not fit in the magwel and told the guys on the Grendel forum they would not work. Of course a year or 2 later some guy with big fat thumbs said they would fit...they wont. Sure you can cram them in there but they will not feed correctly.
 
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The only thing left on ARP website is a box of 40-some 7.62x39 barrels + extensions for $2K 😂. The bolt face depth on x39 is incorrect for factory 6mm ARC though.
Actually its 40something Titan barrel extensions and Titan bolts at about $100 a set so $4000.
for a gunsmith that wants to make a batch of barrels, I don't sell those to the public.
 
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Actually its 40something Titan barrel extensions and Titan bolts at about $100 a set so $4000.
for a gunsmith that wants to make a batch of barrels, I don't sell those to the public.
Meant bolts instead of barrels! My mistake on the dollar figure and as far as x39 I only meant that the Titan bolts are listed as 0.124” recess on the page.
 
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Not having feed problems with 6.5g mostly 123g bullets.
Mostly run 10 round mags target shooting and no problems at all.


Seems like the reviews are similar to every other 6.5G mag out there. They work for 70-80% of the folks, and the other 20-30% have failures. E-Landers, ASC, Cprod, etc all seem to do the same thing with regards to working for some but not others. It's a real shame nobody has cracked the perfect mag code for rounds based off this case, as they're a phenomenal step up in BC compared to 5.56 and let more folks hunt with ARs in states where .243 or some other "not .22 diameter bullets" are the minimum required caliber for some game species.

I wonder if the mag/feeding issues are actually indicative of a wider tolerance margin when it comes to bolts, barrels, etc for 6.5G/6ARC and how they interact with the magwell/lower receiver. Just seems odd folks have had such a varied experience with different magazines, some even using uppers built by the same shop. For instance, my 6.5G upper is a Larue UU kit, assembled by them. The E-Lander 24rd mags wouldn't work for shit, but others with UU uppers sing their praises. Is something off in the magazine QC process which allows for a lack of consistency, or is it an issue derived from the lower they're put in or the upper they're trying to feed?

If 6ARC really is going to some folks in uniform, it would be interesting to see what magazines they are no shit using...
 
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Seems like the reviews are similar to every other 6.5G mag out there. They work for 70-80% of the folks, and the other 20-30% have failures. E-Landers, ASC, Cprod, etc all seem to do the same thing with regards to working for some but not others. It's a real shame nobody has cracked the perfect mag code for rounds based off this case, as they're a phenomenal step up in BC compared to 5.56 and let more folks hunt with ARs in states where .243 or some other "not .22 diameter bullets" are the minimum required caliber for some game species.

I wonder if the mag/feeding issues are actually indicative of a wider tolerance margin when it comes to bolts, barrels, etc for 6.5G/6ARC and how they interact with the magwell/lower receiver. Just seems odd folks have had such a varied experience with different magazines, some even using uppers built by the same shop. For instance, my 6.5G upper is a Larue UU kit, assembled by them. The E-Lander 24rd mags wouldn't work for shit, but others with UU uppers sing their praises. Is something off in the magazine QC process which allows for a lack of consistency, or is it an issue derived from the lower they're put in or the upper they're trying to feed?

If 6ARC really is going to some folks in uniform, it would be interesting to see what magazines they are no shit using...
Agreed. I emailed lancer magpul and a couple others asking about a 6 arc mag for this reason.
 
When you stack cartridges in a mag the top of the first cartridge should touch the bottom of the 3rd and the second should be to the side and between the 1st and third. if you look close from the rear you can see space between them top to bottom. The magwel of an AR15 is not wide enough to allow that proper stacking and the thickness of the mag. It has been like that since 2005 when I purchased my first 6.5CSS(Grendel). The thin mag adds extra pressure to the cartridges and makes them drag as the move up. They either need to make a larger magwel like the did for the SIX8 or the guys making the mags need to make the ribs a little thinner. Not sure if that will decrease side strength and allow the mag to bulge but this has been going on for over 15 years, seems like some company would have figured it out before they sent them to the DOD. The dies to bend the mags cost 100K or that is the price everyone throws out.
ETA- On top of that the Grendel/6ARC cases are larger diameter so the bullet tips sit lower below the centerline of the bore and must travel up further to align and enter the chamber. They can't raise the feed lip of the mag because they will contact the bottom of the carrier.
They could design a carrier like the Armalite AR10 which would allow the bullets to sit higher but then all G mags would need to be redesigned or the square mag catch hole would need to be lowered on the mag to raise the feed lips. Neither is really a big deal but no one ever does anything about it.
 
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When you stack cartridges in a mag the top of the first cartridge should touch the bottom of the 3rd and the second should be to the side and between the 1st and third. if you look close from the rear you can see space between them top to bottom. The magwel of an AR15 is not wide enough to allow that stacking and the thickness of the mag. It has been like that since 2005 when I purchased my first 6.5CSS(Grendel). They either need to make a larger magwel like the did for the SIX8 or the guys making the mags need to make the ribs a little thinner. Not sure if the will decrease side strength and allow the mag to bulge but this has been going on for over 15 years, seems like some company would have figured it out before they sent them to the DOD. The dies to bend the mags cost 100K or that is the price everyone throws out.
Interesting... so do what shield arms did to the g43x mags but for different reasons. Maybe the 6mm arc being another cartridge using that same size case will push someone to finally make a mag for the 6.5g/6mm arc. Get enough of us consumers asking for it, and a secret squirrel dod group, and we might get it.
 
and then there's the 6ARC mags by G that Brownells had for a brief period before they sold out (quickly).
Any word on how they worked? Saw them but they were like $60 each and looked very similar to every other metal mag out there so i didnt buy one. I also wasnt positive i wanted to jump on the 6arc bandwagon yet but now i have a barrel so need to figure something out mag wise.
 
Any word on how they worked? Saw them but they were like $60 each and looked very similar to every other metal mag out there so i didnt buy one. I also wasnt positive i wanted to jump on the 6arc bandwagon yet but now i have a barrel so need to figure something out mag wise.
A lot of the Brownells mags are rebranded ASC mags.
 
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If you know a G dealer, they’re orderable items but Geissele isn’t shipping them. I really wanted to know if they’re a 400% marked up ASC or Duramag product, but not with my own money.
Yeah, same here. Ill probably order a few of the duramag 20rnders just for the convenience of the box of ammo per mag and they have as good of reviews as anything else out there atm that im aware of.
 
From 2005-2009 we used Gen 1 PRI 6.8 mags but their dies broke and when the new Gen 2 waffle mags came out they didn't work as well.
A 10 round LWRC SIX8 mag may work since they are shorter and possibly stiffer than the 30 rounders I tried. Of course it takes LWRC SIX8 receivers to use them.
 
Honestly, I don't remember how many rounds I was putting in them. Or the 30rd'rs. When I slapped the gun together I didn't even think about using Grendel mags. I just reached for any old AR mag and laid my hand on a 20rd PMAG. Did load development and shot a Team match with it. Put it away and a year later bought a JP VMOS BCG for it and when I broke the gun out to rezero with the new BCG it was the first time it occured to me that I should've been using Grendel mags and the PMAGs "shouldn'tve" worked. I throated the barrel out and re-did load development shooting PMAGs the whole time. That was about 6 months ago.

I'll break it out this weekend and shoot it. I'll see how many rounds I can get in there.
Ill have to try the 20rnd ones, i have quite a few of those if they work on my gun.
 
Seems like the reviews are similar to every other 6.5G mag out there. They work for 70-80% of the folks, and the other 20-30% have failures. E-Landers, ASC, Cprod, etc all seem to do the same thing with regards to working for some but not others. It's a real shame nobody has cracked the perfect mag code for rounds based off this case, as they're a phenomenal step up in BC compared to 5.56 and let more folks hunt with ARs in states where .243 or some other "not .22 diameter bullets" are the minimum required caliber for some game species.

I wonder if the mag/feeding issues are actually indicative of a wider tolerance margin when it comes to bolts, barrels, etc for 6.5G/6ARC and how they interact with the magwell/lower receiver. Just seems odd folks have had such a varied experience with different magazines, some even using uppers built by the same shop. For instance, my 6.5G upper is a Larue UU kit, assembled by them. The E-Lander 24rd mags wouldn't work for shit, but others with UU uppers sing their praises. Is something off in the magazine QC process which allows for a lack of consistency, or is it an issue derived from the lower they're put in or the upper they're trying to feed?

If 6ARC really is going to some folks in uniform, it would be interesting to see what magazines they are no shit using...
I'm wondering if the gas system / components and adjustments some people have just don't work well with any particular mag or any of them.

If you just stuff a 6.5g / 6arc upper on your old 223 lower you should lower your expectations of reliable functionality.

Normally anything you buy from a vendor is grossly over gassed to begin with in any caliber. Quick allert, trigger all the vendors to defend their shit.

Fact remains a heavier buffer, flat wire spring and agb will probably get any of the mags to work.
 
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The quality really seems to be batch dependent, is why you will find reports of every brand working and not.
E-Lander has been the bulk of mine and things vary wildly depending when I bought them. Some were perfect and required no adjusment out of the bag. I've seen the mag catch slot cut so low it would jam the feed lips into the bottom of the BCG. The height of the front of the mag body has needed ground down or ramped depending where it was. I've had to reverse the springs in others to correct follower tilt. Word is the springs are made in Italy and the rest Israel and assembled there. They clearly do not have consistency.
 
Just got some Brenton mags in. That 15th round doesn’t really like to be loaded and I think it’s tensioned too tightly to feed well. Aside from that, they are the only mags that don’t drop free from my Mega lower. Pmag, duramag, GI mag all drop. We'll see how they feed…in manual/test manipulation I see gouging all down the projectile jackets regardless of which mags I use.
 
Just got some Brenton mags in. That 15th round doesn’t really like to be loaded and I think it’s tensioned too tightly to feed well. Aside from that, they are the only mags that don’t drop free from my Mega lower. Pmag, duramag, GI mag all drop. We'll see how they feed…in manual/test manipulation I see gouging all down the projectile jackets regardless of which mags I use.
the gouging of the projectile jackets is probably being caused by the knife-sharp edges of the barrel-extension feed ramps. If you remove the barrel from the upper, you can do a pretty good job of de-burring and polishing those sharp edges so that the projectile gets a nice smooth ride up the feed ramp into the barrel feed cone.

and while you're at it, knock off the adjacent sharp edges on those 2 barrel extension lugs at 3 o'clock that do a good job of gouging the brass when being extracted.

this is usually an extra-credit exercise for the motivated upper-assembler.