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98's 6mm ARC


98Z5V

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1 hour ago, RedRiverII said:

"Man alive,  (hangs head) that's improper.  Acting normal just don't fit ya' son.  Why let any sort of normal creep into your style.  You dun let down the troops boy!"

Hey, if the A5H2 shows up in stock somewhere, while I'm waiting my 1~3 months for the LaRue upper setup - then I'll certainly buy it.  Or 5 of them.  In the meantime, if they never, ever show up - I have a plan.   I know it sounds quite odd, but I'm trying to be the voice of reason and rationale here...   :thumbup:

 

 

 

 

 

For what that's worth...   :banana::lmao:

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So, here's the real deal with all this shiit.  I won't mince words.  The 6.5 Grendel was designed as the perfect 200~800 yard AR15-platform cartridge, and it was released at SHOT Show 2004, but it was finalized before that.  I ignored the Grendel until 3 years ago, then made the plunge.  Love at first shot.  It truly is the perfect cartridge for the AR15 platform, and I don't know how I blew it off for over a decade. That first shot literally morphed into FIVE guns...  I shiit you not.  Grendel RULES the AR15 world.  There is no doubt about that.

So, this is what's up - I've talked Grendel up all over this place, and corrupted a few...  @Matt.Cross and @Armed Eye Doc come to mind immediately...  It's reallyTHE badass cartridge for the AR15 platform, hands down. It really is.

Then, the .224 Valkyrie comes out a couple years ago.  It's just a necked-down 6.8SPC cartridge, to .224, to shoot the REALLY heavy .224 projectiles - I'm loading 88gr Hornady ELD-M projectiles for it.  Yeah, I jumped in it.  I wanted to compare it to the Grendel - because everyone else said it was a Grendel-Killer.  Not even...

Here's the original SPR Grendel, and the Valk I built to "take down the Grendel..." - that never happened, by the way, ballistically...

That original 18" SPR Grendel is on the top, and that Valk is below it. I built those two bitches SO SIMILAR, just to make sure nothing was left on the table.  Even down to the VG6 2-port muzzle brake and VG6 CAGE device. The Grendel won.

 

P1080761.thumb.JPG.f916c9d22c1cdd55d41180089dc1a74f.JPG

 

Now, somewhere along the line of all this 6 ARC development, someone compared the 6 ARC to the .308 WIN load of the Hornady 178gr ELD-X...   hehehehe...  Imagine that.  When I built the Mk11 1/2 a year ago, that 178 ELD-X launched - and it was WAY BETTER than the 178gr HPBTs that I was using before.  So... I built the gun, bought the projectiles, and came up with a WHOLE NEW LOAD for ALL my .308 Win guns, based off that Mk11.  And it is BADASS.   So, some nutbag online compared 6 ARC to the .308 Win 178 ELD-X...   Hmmm...  That's ANOTHER thing that made me want this 6 ARC - because I'm gonna find out, for real.  So here's the other "contender" in this 6 ARC gunfight:

P1080762.thumb.JPG.db902d284ae55fbf7795a70fb9661f42.JPG

Oh, same brake and CAGE device...  18.5" .308 Win Match barrel, Fulton Armory, Kreiger-Criterion (old days), compared to Ballistic Advantage Mk12 18" SPR barrels...  this is gonna be good, men... :popcorn:

So, WTF...  Let's toss all this shiit at the walls, and throw in some 5.56 Match loads.  And a Mk12 Mod 1, in the mix. My Mk12 5.56 handloads are 2789.75fps, averaged.  You need to get the 75 or 77gr 5.56 projectiles to 2750fps to really "see the magic" that is all Mk12, and I Exceeded Course Standards on my handloads for my Mk12.  That's the chrono number of them, through the 18" barrel.  Not a guess-timate.  I've got that load down to a science, and this thing is supersonic to 850 yards on the G7 drag models - and proven out to 850, too. By a BUNCH of other people here that have shot it.  It's pretty stupid, for a 5.56 gun.  :hail:

P1080763.JPG

Last but not least - it doesn't matter what happens on paper, or on steel at distance - everything I own has to measure up to the 16" Grendel Mod H.  That little bitch is my kryptonite.  That thing smokes everything else, as an overall gun, hands down.  No matter how this cartridge shakedown works out, how perfect I can make the 18" 6 ARC LaRue SPR to the 18" Grendel SPR and the 18" .224 Valk SPR - it needs to out-maneuver and out-shoot the 16" Grendel Mod H, in an all-around desert battle...   The Mod H Grendel currently rules the all-around world, in my dry-ass world...   That's my bitch, on the bottom in this pic.  :thumbup::hail:

P1080764.JPG

Edited by 98Z5V
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So, again...  Why am I doing this?  Dumbass-Attack?...  :bitchslap:

Nope.  I KNOW the Grendel.  Very well, and very well tested out to distance, out here in my world.  This is a 6mm Grendel - this 6 ARC is - and I know what my Grendels can do.  When I can center-punch the 850-yard steel with a 12.5" barreled Grendel pistol, with 10 mils of drop dialed on a 4x scope... - I know what the Grendel is really capable of. 

And this thing looks VERY promising, as a "6mm Grendel."  I think it's all that they say it is. And I already bet a complete LaRue gun on it, just to see.  :thumbup:

Hey, if it sucks, and isn't all that - then I have a complete LaRue 18" Grendel gun out of the deal...   And I KNOW that fucker will perform!...   :banana:

Edited by 98Z5V
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All you guys that read my Valk Shiit-Talking...  don't be discouraged.  It's a great cartridge, and I'm glad I built one.  Very glad that I built it.  It really is good, but it's no Grendel-Killer, like all the hype made it up to be.  It's FAR superior out of a small-frame AR than 5.56 is.  I feel like I'm qualified to state what you can achieve from a 5.56 gun, at distance, too.  You CAN stretch those fuckers out there, for real, and I've done it to 850 yards in a 13.9mph full-value wind, with the 75gr Hornady HPBT handloads that I have...    - and it SUCKED.  BAD.    Never give up, though...  If you're gonna be dumb, you better be tough...  :bitchslap:  :laffs:

But anyway, on the Valk stuff.  You can run up to a 90gr projectile with the common Valk 1:7" twist barrels that are out there.  DO NOT get sucked in, on those "magic" Sierra 95gr Match King projectiles, and think you'll be The King Of The World with those...  You NEED a 1:6.5" twist barrel to run those bitches, don't let anyone tell you otherwise.  There are very FEW 1:6.5" twist barrels out there... That's the whole reason I'm loading the 88gr Hornady ELD-Ms for my1:7" twist BA SPR Valk barrel.  I'm not gonna get any better than that, and the barrel is completely kickass.

***  Oh, and because I'm a complete Hornady Whore, for projectiles...  That's the other reason...  No Sierras in THIS house... well, except those .25 cal 90gr GameKings in the 25/45.  Those fuckers ROCK in that load/gun...   :hail:

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Y'know I do thank you often for posting,  not every post which bubbles from that cranium of yours,  but many.  With some polishing,   and grammar grease,  you post magazine worthy articles.  Let's call them spikes,  that's newspeak for inserting special messages.  Well old school message inserting.  The above speaks loudly to me.  For us who have less knowledge regarding ballistics and handling of weapons we get fine information .  We also get carried away when your hair catches fire and we watch it burn.  This last sentence is merely a metaphor for experiencing passion displayed.  I've never been out west to one of the GATHERINGS so I don't reference any actual hair burnings,  except I seem to remember someone falling into the pit.  Anyway,  If Vegas had odds on the new cartridge for the US Army,  I'd place a wager on the 6ARC.  I thought the 6.8 SPC was going to be it, as proof I own 600 casings for that round,  sitting in the vat and stewing.  

All the rifles we own are perfectly good as long as they go bang and we aim well.  I don't think any game shot will argue "  Hey,  that 6.8 ain't allowed I prefer a Grendel."  I am way behind in the knowledge of what is best.  I want the best but,  308,  556,  and 260Rem  is good enough.  I am invested in the 6mmARC and building as I speak.  What I have available is a 600 yd. range which is 2 hrs. away.  That's a long range drive when you in your late 60"s.  So when I'm finished with the 6mmARC I'm making the drive with them all. 

We are among the vanguard with this round.  You can bet your petunia's we're on the radar.  All this info is being carefully examined.  We want a round that delivers a better punch at distance,  and not just a round that lasts the trip down range for the US Services.  Why?  In order to put the bad guys down at longer distances.  

How is that measured?  How much punch a round has at a given distance is my inquiry?  Gotta walk the pup,  he's giving me the eye.

 

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I’m curious if you guys have any experience with this package https://www.opticsplanet.com/leapers-utg-model-15-standard-a2-butt-stock-assembly-black-rb-t469b.html
This same set is on Big Daddy Unlimited right now for $43.99. I know Leapers UTG is lower end stuff for the most part, but just curious if anyone has tried out their rifle length buffer and spring? $44 is a hard price to beat if their buffer stuff is within spec and functions fine, considering it includes the stock and recoil parts. I had planned on trying an A1 stock setup, but it’s about $100 for an A1 stock and buffer parts from just about anywhere. 

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2 hours ago, DayWalker said:

I’m curious if you guys have any experience with this package https://www.opticsplanet.com/leapers-utg-model-15-standard-a2-butt-stock-assembly-black-rb-t469b.html
This same set is on Big Daddy Unlimited right now for $43.99. I know Leapers UTG is lower end stuff for the most part, but just curious if anyone has tried out their rifle length buffer and spring? $44 is a hard price to beat if their buffer stuff is within spec and functions fine, considering it includes the stock and recoil parts. I had planned on trying an A1 stock setup, but it’s about $100 for an A1 stock and buffer parts from just about anywhere. 

It can't be bad - it's hard to mess up rifle recoil systems.  As long as that buffer is 5.900" long and weighs 5.4oz, and the extension is 9 11/16" deep - you're good.  Worst case scenario - the spring might suck.  New Armalite M15 rifle springs are about 5 bucks.  :thumbup:

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31 minutes ago, 98Z5V said:

It can't be bad - it's hard to mess up rifle recoil systems.  As long as that buffer is 5.900" long and weighs 5.4oz, and the extension is 9 11/16" deep - you're good.  Worst case scenario - the spring might suck.  New Armalite M15 rifle springs are about 5 bucks.  :thumbup:

:thumbup: Nice. That was my thought as well, figured it’s difficult to mess up rifle buffers. 
 

I’m getting more and more pumped for this round fellas, I think I luck boxed my way into a seriously nasty rifle. Kotaboy put out another good video on 6mm this afternoon, he went deep into the ballistics, comparing it with real world numbers against 308 and 6.5 Grendel. He seems completely sold on 6mm already. Worth a watch if you have a few mins to kill.

 

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2 hours ago, DayWalker said:

 Kotaboy put out another good video on 6mm this afternoon, he went deep into the ballistics, comparing it with real world numbers against 308 and 6.5 Grendel.

 

That was good - the 6 ARC was right there with the .308, for drop-over-distance, but that's information from his buddy, on his buddy's .308.  Also, his Grendel velocity is WAY down, compared to what I get from my load, through my guns.  Shiit,my 12.5" Grendel is getting the velocity that he's stating for his Grendel velocity.  His buddy was getting 2550fps on a .308 Win 168gr load.  I'm pulling 2530fps with my 178 ELD-X load, through an 18.5" barrel.  We don't have enough data on his buddy's .308 gun to mash it all out.  Also, he's fucking up his software - I froze the screen, and he's got his sight height set at the default bolt gun stuff...  1.5" sight height.  AR sight height is 2.5"...   So, his data needs work.  Garbage in, garbage out.  Every detail matters when you're making up a DOPE/Drop chart...  His Grendel data is 2370fps through an 18" barrel...  I caught that when I rewatched it, and he stated the barrel length...

My Grendel numbers are:  12.5" = 2369fps (I'm right there in my 12.5" - where he is with his 18"...) // 16" = 2495fps // 18" = 2534fps...  

Hell, my Grendels beat my old .308 Win load, with the 178 HPBT Hornadys - at 850.  I haven't had my new 178 ELD-X load together long enough to go run it against the Grendel load at 850.  I'll suck up the heat here, and get out early on a Sunday morning and set up the 500 and 850, and get it on between those two. 

This is gonna get good, brother - VERY good.  :thumbup:

Sidenote:  I much prefer JBM Ballistics for computing this stuff.  It's far better than that program he's using - but it doesn't produce those graphic charts, showing drop over distance, with the arcs and all.  Bryan Litz worked on the JBM software.

Go to the "Ballistics" tab, and all the Calculators will come up.  I used "Simplified Trajectory" most of the time, but if I need a specific hunting load chart made up, I'll use the "Trajectory" one - way more details to input, better results out.  If I get REALLY freaky on a specific load, I'll use that new "Modified Point Mass Trajectory" table.  It's pretty complicated, and I don't quite have that one down yet... 

https://www.jbmballistics.com/index.shtml

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@DayWalker, here's some really interesting shiit, brother...  and why I geek out on this part of it...

My 18" Grendel 123 ELD-M handload is rocking 2534fps, and it's 8.5 mils of drop at 850 yards...  G7 BC is 0.255. Sectional Density of the projectile is 0.252.

My 18.5" Mk11 178 ELD-X handload is rocking 2530fps, and it's 8.5 mils of drop at 850 yards...  G7 BC is 0.268. Sectional Density of the projectile is 0.268.

Hmmm...  just made this more interesting, didn't I?...   :popcorn: Those two are made to compete against each other, like peanut butter and jelly...   I just leveled the playing field between the 6.5 Grendel and that magic 178 ELD-X .308 Win load that all this 6 ARC information keeps comparing to...  Those are my handloads (velocities), though, and they're certainly not the numbers that he's getting for his Grendel velocity, and the numbers reported for his buddy's 168gr .308 Win load.

So, this 6 ARC, once I get it all load-developed, should crush both of them.  Factory ammo?  We'll see.  He reported 2605 for his 6 ARC velocity, but I ran it through another calculator (Shooter's Notes barrel velocity estimator), based on the numbers on the box - 24" barrel = 2750 fps.  The number I came up with is 2617 fps for an 18" barrel.  And that's before I start loading this one up... That's the Factory Ammo number - Hornady 108gr ELD-M Match loaded ammunition, from Hornady.

Here's the charts I'm referencing for the numbers that I get - my handloads...

1707958586_18Grendel123ELD-M2534fpsFinalLoad.thumb.png.a20aefe3d7e0ae01f0bde2e166f8935e.png

768506821_Mk11Mod0.308Win178ELD-X2530fps.thumb.png.f3d5b53223d2b4049337ffc1afdf7def.png

Shiit is about to get real, men...  :banana:

Edited by 98Z5V
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Leaving in 5 hours, to pit the 18" Grendel against the Mk11, at 500 and 850. Results will be posted here. 

It's supposed to be 117 here tomorrow, so I'm going out there early, and not staying long.  SW Desert sucks in the summer, men. 

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11 hours ago, 98Z5V said:

Leaving in 5 hours, to pit the 18" Grendel against the Mk11, at 500 and 850. Results will be posted here. 

It's supposed to be 117 here tomorrow, so I'm going out there early, and not staying long.  SW Desert sucks in the summer, men. 

You’re a brave man my brother, 117 is well past my cut off. I’ll be interested to hear the results though. 

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Well, I got out there at 0630, and got home at 1045.  It was already 113* before I left out there, and....   DAMN!  Was it was weird out there...

Everything was different.  I made and tested that 178 ELD-X load, and it was 50*, I was running the altitude for where I was (camp location) at 1390 feet, baro pressure was 29.80 in/Hg, and humidity was almost nothing.   .308 Win load, badass to the bone, like a laser.  8.5 mils of drop at 850 yards, and I confirmed that the very next day after I finalized that load...

Okay, so today...   Fuckin' WEIRD.   This thing was 7.0 mils of drop at 850 yards.  I've never had a .308 Win load that will do that.  At first, I dialed 8.5, and I was shooting way over the steel.  I dialed it back to 0, and just started holding, until I was on target.  Once 7.0 even was determined to be the magic hold, I dialed 7.0 mils, and whack after whack on the steel.  Unreal for a .308 Win load.

Weather - as soon as I figured that drop out:  At the time right after shooting and re-doping it, it was 105*, baro was 28.38 in/Hg, altitude at the long-distance location is actually 1458 feet, and humidity was 22.6%.

Just plugging weather into the calculator (alone, just the weather differences) brings the drop to 7.7mils at 850 yards.  Play with the muzzle velocity (2530 fps when I made this load, weather data up top)...   I mess with the muzzle velocity in the calculator, along with the weather changes, and it's 2630 fps to make 850 yards a 7.0 mil drop correction...

The 18" Grendel was just as weird, but I didn't put the time into that one to figure it out.  Eff it.  I'll wait 'til it's cooler to mess with that. 

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9 minutes ago, Radioactive said:

Doesn’t look so hot.

It's deceptive.  It looks like a Long Range Dream Come True - until you're in it.  They best way I can describe so others can "feel it" is to pre-heat your oven to 325*, and when the buzzer goes off, open the oven door and stick your head in there...   :lmao::banana:

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