A 6MM ARC upper on the economic side

[troy fairweather]

Well id say it's shooting pretty good, was like 30° this morning and could only get the target out to maybe 90 yards since there was plowed snow at the 100 line. Left is factory hdy 105 right is hdy 108. Only 3 shot groups trying to save on ammo but I'd say the er.shaw barrel shoots.
The right is two groups, just dropped the turrets down 4 clicks.
I still need to get pics of the gun was to cold when shooting to get a picture of the gun.

 

[N555]

I guess I don't see the point.
6arc costs about $1 per shot or around 2x as much per shot as 223 or 5.56, its just about up there with the cost of 308 ammo.
For something like 6.5 Creedmoor or 308 paying that much per shot I get it.
Sell it to me. What's 6arc do that's so special?

 

[Gtscotty]

Just be mindful as the weather warms this spring. Powders rarely get more temperature sensitive than Leverevolution - it’s a powder I would highly recommend using the temperature correction features of your ballistic app, or at least catalog velocity change over daily temps and correct MV in the calculator.

Yep, I like LVR in the ARC, but I'm seeing some temp sensitive to the tune of ~ 2.2 fps/deg. I still use it, although I had hoped that Staball Match would be a better fit for the cartridge.

Had the ARC out yesterday giving 105gr Match Burners a try, it was slower in the cold, but still did ok. This barrel was an X-Caliber lightweight that I ordered on sale, not too pricey, maybe $300 or so, and I've been happy with it. The 108gr load groups better @~2,640 fps in warmer weather, but the barrel really prefers 100gr TGK.

Sell it to me. What's 6arc do that's so special?

Nah, no one needs to justify their purchases to you or sell you anything, if you don't want one, don't buy one.

 

[troy fairweather]

What's everyone getting for speed with factory ammo out of there arc's, was to cold for me to try and chrno any yet.

 

[Varminterror]

I guess I don't see the point.
6arc costs about $1 per shot or around 2x as much per shot as 223 or 5.56, its just about up there with the cost of 308 ammo.
For something like 6.5 Creedmoor or 308 paying that much per shot I get it.
Sell it to me. What's 6arc do that's so special?

Take a look at the recoil of getting a 175 class 30 cal bullet to stay supersonic past 1000, and take a look at the powder 308win eats to get there. Hornady ELD's are super cheap for 178 ELD's, same price per bullet as 108's right now, but typically, 30cal bullets cost a dime to a quarter more than 6mm bullets, and eating over 60% more powder proves your math is incorrect, stating it plainly. The 6.5 creed isn't so different. 140's over 42grn to trace a similar trajectory which is achieved with 105grn over 28grn... And the ARC is running power pressure to get there. And of course, we're doing it in an AR-15 instead of an AR-10, carrying a rifle a pound and a half or two lighter (and not conceding to the straw man of available DPMS GII/Ruger SFAR/Mega AR12.5's which are highly proprietary in componentry - which are STILL heavier and longer than an equivalently built AR-15, with poorer balance).

What do we get over a 223/5.56? Longer supersonic distance, better retained impact energy, 50% greater to twice the bullet weight for much greater impact at distance, all with only about 10-15% greater powder use.

 

[Gtscotty]

What's everyone getting for speed with factory ammo out of there arc's, was to cold for me to try and chrno any yet.

I got right around 2,675 fps with 108gr ELD and 2,700 fps with 150gr black ammo in my 21" with temp around 60 deg. I think my 18" ran in the 2,570 fps range (was chronoing other rifles too and forgot to write it down), but that was in colder 30-40 deg weather.

 

[troy fairweather]

I got right around 2,675 fps with 108gr ELD and 2,700 fps with 150gr black ammo in my 21" with temp around 60 deg. I think my 18" ran in the 2,570 fps range (was chronoing other rifles too and forgot to write it down), but that was in colder 30-40 deg weather.

Ok pretty good I'd like if my 22" could get the 100+ grainers up to 2700 ish 2650 would be fine tho. I want to try some 85-87 be real cool if they can hit 3000 out of my 22" arc.

 

[Tinker-S]

Well id say it's shooting pretty good, was like 30° this morning and could only get the target out to maybe 90 yards since there was plowed snow at the 100 line. Left is factory hdy 105 right is hdy 108. Only 3 shot groups trying to save on ammo but I'd say the er.shaw barrel shoots.
The right is two groups, just dropped the turrets down 4 clicks.
I still need to get pics of the gun was to cold when shooting to get a picture of the gun.

View attachment 1141155

Nice!
I just loaded some ammo with LEVERevolution to go to the range this weekend. Everybody says that LR is the best propellant for this caliber. I will post pics.
My range buddy is waiting on his upper from Shaw, and he went to purchase as much ammo as he could find.

 

[Tinker-S]

What's everyone getting for speed with factory ammo out of there arc's, was to cold for me to try and chrno any yet.

I have not been able to get ammo at my local stores, and my favorite e-store is out of inventory.

 

[Tinker-S]

Take a look at the recoil of getting a 175 class 30 cal bullet to stay supersonic past 1000, and take a look at the powder 308win eats to get there. Hornady ELD's are super cheap for 178 ELD's, same price per bullet as 108's right now, but typically, 30cal bullets cost a dime to a quarter more than 6mm bullets, and eating over 60% more powder proves your math is incorrect, stating it plainly. The 6.5 creed isn't so different. 140's over 42grn to trace a similar trajectory which is achieved with 105grn over 28grn... And the ARC is running power pressure to get there. And of course, we're doing it in an AR-15 instead of an AR-10, carrying a rifle a pound and a half or two lighter (and not conceding to the straw man of available DPMS GII/Ruger SFAR/Mega AR12.5's which are highly proprietary in componentry - which are STILL heavier and longer than an equivalently built AR-15, with poorer balance).

What do we get over a 223/5.56? Longer supersonic distance, better retained impact energy, 50% greater to twice the bullet weight for much greater impact at distance, all with only about 10-15% greater powder use.

Not to mention how cool the little guy looks when compared to 308!
BTW, the recoil is, well, next to nothing!

 

[Tinker-S]

I got right around 2,675 fps with 108gr ELD and 2,700 fps with 150gr black ammo in my 21" with temp around 60 deg. I think my 18" ran in the 2,570 fps range (was chronoing other rifles too and forgot to write it down), but that was in colder 30-40 deg weather.

Forgot to write it down?
My chrono retains all of that for me, and I am glad! I would lose my fingers if they were not attached to my hand!

 

[troy fairweather]

Nice!
I just loaded some ammo with LEVERevolution to go to the range this weekend. Everybody says that LR is the best propellant for this caliber. I will post pics.
My range buddy is waiting on his upper from Shaw, and he went to purchase as much ammo as he could find.

Ya I may get a few more boxes of arc( shop had 30 boxes last time there) to get the barrel to speed up and break in, plus have that brass. I've got 2 pounds of lever so be good for this year, need to see what powder is good for the 70 and lighter bullets. Probably cfe 223, I still need some dies may get the hornadys.

 

[Tinker-S]

I found some .243 107GR SMK on "sale" for about $0.32 on a pack of 500 projectiles. And I also got some .264 120GR SMK for my 6.5 Grendel, but I only got 100. I have the new 6MM ARC to work with.
I am also waiting on 7.62x39 brass to convert for the Grendel, because all of the Grendel brass will be now 6MM ARC.

 

[Tinker-S]

Ya I may get a few more boxes of arc( shop had 30 boxes last time there) to get the barrel to speed up and break in, plus have that brass. I've got 2 pounds of lever so be good for this year, need to see what powder is good for the 70 and lighter bullets. Probably cfe 223, I still need some dies may get the hornadys.

I got the Lee dies, but I am looking for/waiting on an RCBS Small Base die set. When I started reloading, the small base dies worked the best for my Grendel.

 

[troy fairweather]

Seen some think 90 eld-x at the gun shop up by my dad for $45 think that would be a nice deer load of there about 2800 or so and still have pretty good bc. I want to get some 75 or 87 vmax and see how they do for a coyote load. Really hope some speers come in stock there cheap and shoot good, got half a box of 100 interlocks they will be good for deer to try out.

 

[troy fairweather]

I got the Lee dies, but I am looking for/waiting on an RCBS Small Base die set. When I started reloading, the small base dies worked the best for my Grendel.

From what I seen the rcbs are almost to small, guys getting the belted case. Think rcbs has 2 different dies now. I figured hornady made the round so there dies should be good tho I prefer rcbs.

 

[Tinker-S]

Seen some think 90 eld-x at the gun shop up by my dad for $45 think that would be a nice deer load of there about 2800 or so and still have pretty good bc. I want to get some 75 or 87 vmax and see how they do for a coyote load. Really hope some speers come in stock there cheap and shoot good, got half a box of 100 interlocks they will be good for deer to try out.

Yeah.
I found a pack of 500 .243 70GR SMK at PSA for a really good price! I should have picked up 2 or 3 packs. They were sold out after I finished my order and went back for more!

 

[Tinker-S]

Yep, I like LVR in the ARC, but I'm seeing some temp sensitive to the tune of ~ 2.2 fps/deg. I still use it, although I had hoped that Staball Match would be a better fit for the cartridge.

Had the ARC out yesterday giving 105gr Match Burners a try, it was slower in the cold, but still did ok. This barrel was an X-Caliber lightweight that I ordered on sale, not too pricey, maybe $300 or so, and I've been happy with it. The 108gr load groups better @~2,640 fps in warmer weather, but the barrel really prefers 100gr TGK.

View attachment 1141166



Nah, no one needs to justify their purchases to you or sell you anything, if you don't want one, don't buy one.

How do you like the 105 Match Burners?
I have a 500 pack, and I will start to load them with LR.
I like the Match Burners on most/all of my ARs, and also on a 243 bolt gun. They perform really well, and are not very pricey.

 

[Gtscotty]

Forgot to write it down?
My chrono retains all of that for me, and I am glad! I would lose my fingers if they were not attached to my hand!

Yeah, my magnetospeed took a dump, so I'm back to the F1 Chrony until I figure out if I want to get another MS, or go with a Labradar. Anyway, I had to shoot out in the open to get readings, was racing the rain and the main goal was to get velocities for my SFAR with different brass makes to figure out the effect. I remember shooting, don't remember writing down, and don't have a picture... Did get the SFAR velocities though.

 

[N555]

What math? I was only talking about factory ammo.
In a 16 inch and shorter gun 6arc is probably the way to go.
My most accurate 223 round for carbines only does about 2,500fps out of a 16 inch barrel. Might as well make a bigger hole with twice the bullet.

I find 6arc interesting enough to at least look at uppers and 6mm silencers. 223 in a carbine is less than ideal.

 

[Tinker-S]

Yeah, my magnetospeed took a dump, so I'm back to the F1 Chrony until I figure out if I want to get another MS, or go with a Labradar. Anyway, I had to shoot out in the open to get readings, was racing the rain and the main goal was to get velocities for my SFAR with different brass makes to figure out the effect. I remember shooting, don't remember writing down, and don't have a picture... Did get the SFAR velocities though.
View attachment 1141223

Cool!
Get yourself a Labrador!
I have one, and I like it. I do not understand what the fuzz is all about when I hear people talk about how difficult it is to aim the thing!

 

[Gtscotty]

Ok pretty good I'd like if my 22" could get the 100+ grainers up to 2700 ish 2650 would be fine tho. I want to try some 85-87 be real cool if they can hit 3000 out of my 22" arc.

You should be able to get close anyway, I tried 85gr sgk HPs with LVR in my 21" and got almost to 3k.

 

[Varminterror]

Yeah, my magnetospeed took a dump

Have you called Ryan yet?

 

[Gtscotty]

Have you called Ryan yet?

Nah, not yet this time, last time I emailed and the answer was to buy a new bayonet at a mild discount. I expect it will be similar this time, I'm not remotely in warranty. The failure mode was different though, last time it just started erroring out and never came back, this time I got a smattering of errors and then it gave me a string of readings that I knew were ~200 fps to ~250 fps low. To be fair, it's an old Sporter model and it's kind of a pain to use anymore because I shoot suppressed nearly all the time, and also don't have a phone with a 3.5mm port to plug it into anymore. So maybe a V3 or better yet a labradar would be the way to go instead of limping my Sporter along.

That said, so far, using the old F1 Chrony for a bit of load development and then letting real drops at range tell me the rest of the story, is working pretty satisfactorily.

 

[Gtscotty]

How do you like the 105 Match Burners?
I have a 500 pack, and I will start to load them with LR.
I like the Match Burners on most/all of my ARs, and also on a 243 bolt gun. They perform really well, and are not very pricey.

I like them thus far, only shot 200-300 through the 21", and honestly, in my rifles 29.2gr to 29.3gr LVR seems to work really well with the 100gr to 108gr bullets I've tried in general and these have been no exception. I've shot a lot more of the 112gr in my 6GT, and really want to like them because the BC is excellent, and they carry really well out past 1k, but they aren't as consistent as something like the 109gr Hybrids. Still, for the price of the MBs, I've been pretty happy for informal plinking and practice.

One thing to be careful with on the 105gr is seating depth, they hit the lands around 2.2" coal in my 18" and just a little further out in my 21".