6 ARC powder consensus for heavies in AR

[gopherslayer]

I’m trying to consolidate my powder stock so I don’t have 10 different powders for my rifles. Looking at dumping the Grendel and going 6 ARC and strictly shooting 95gr-108gr. 18-20” barrel.

I would like to believe that factory ammo would be consistent but my experience with Grendel during the last drought was different lots were all over the map accuracy wise so if I go this route I’ll be committed to me doing the loading. I started loading for the Grendel but lost interest in it.

So which powder should I start buying for the ARC?

 

[Dogtown]

LEVERevolution (LVR) is probably the best optimized powder for the cartridge, giving the best balance of velocity/pressure. It’s dirty AF though, especially suppressed, but that’s a small price to pay for performance.

CFE223 is also in the same zone though not quite as popular.

I’ve tested a lot of different powders for 6ARC shooting 95s to 110s and LVR basically works best across the board. If you wanted to choose a powder that was also good for .308WIN, for example, Varget and TAC are decent options. I didn’t get great performance out of them, but not bad. N540 kind of surprised me how well it shoots, though velocities were about 100fps slower out of a 16.5” barrel.

 

[JR1200W3]

The reason we all end up with so many powders is different barrels like different powders. You should probably get a load sorted and then when you know what shoots best buy more of that.

For Grendel based cartridges you can shoot anyone of:

TAC
8208
4895
Varget
CFE223
LeverRevolution
2520
StaBall

 

[gopherslayer]

I use a lot of Varget and H4350. Benchmark in my 223s with heavies and was hoping I could use Benchmark in the Arc but that looks like a light bullet powder.

 

[Dogtown]

H4350 is tool slow, but you can use Varget with 6ARC. It’s just not a great powder for it, from what I’ve found.

 

[Clint H]

+1 on LeveRevolution being the general favorite for 6ARC. It's a progressive burn-rate powder, so it maintains peak pressure for a longer time interval, hence where the velocity comes from. Downsides are it can be dirty, and some have found it to have a high ES.

As @Dogtown said, Vit N540 is another good choice, cleaner, but a bit less velocity. Also, it has a very hot flame temp due to the nitro glycerin (double-base), so barrel life can suffer. N140 is cooler (single base), but you'll sacrifice another ~50ft/sec.

A final one I hear mentioned often is AA2520. Less velocity again, but good ES/SD and clean. Just tends to be temp sensitive.

 

[Dogtown]

And when I say "N540 kind of surprised me", shooting ten round strings with a variety of powders loaded nowhere near max, N540 produced noticeably more consistent results (lowest SD/ES and tightest MR). Specifically I was using 26.5gr of N540 with 103 ELD-X and GM205MAR loaded to 2.245" COAL. But it's still kind of slow at 2350fps and might be worth playing around a bit with higher powder charges.

 

[LRRPF52]

I’m trying to consolidate my powder stock so I don’t have 10 different powders for my rifles. Looking at dumping the Grendel and going 6 ARC and strictly shooting 95gr-108gr. 18-20” barrel.

I would like to believe that factory ammo would be consistent but my experience with Grendel during the last drought was different lots were all over the map accuracy wise so if I go this route I’ll be committed to me doing the loading. I started loading for the Grendel but lost interest in it.

So which powder should I start buying for the ARC?

I wouldn’t dump Grendel just yet.

Look at the velocity you can get with 90gr TNT or 95gr V-MAX vs the 6mm.

Also, something has been going on with powders I think because data for some of the common ones has changed noticeably. Especially 8208XBR.

I was going to add a 6mm AR all these years and never got around to it, but when I ran the numbers and compared to what I’m seeing with 6.5mm 100gr Hornady ELD-VT, 105gr Sierra Blitzking, and 107gr SMK, they overlap with the 6mm and out-perform it at most of the ranges, given the same barrel lengths.

I used real-world data I’m seeing at 700-1000yds with Grendel, then compared with Hornady’s doppler radar program for the 6mms. That new 100gr ELD-VT load is really flat and they aren’t even pushing it.

 

[st1650]

N540

 

[st1650]

And when I say "N540 kind of surprised me", shooting ten round strings with a variety of powders loaded nowhere near max, N540 produced noticeably more consistent results (lowest SD/ES and tightest MR). Specifically I was using 26.5gr of N540 with 103 ELD-X and GM205MAR loaded to 2.245" COAL. But it's still kind of slow at 2350fps and might be worth playing around a bit with higher powder charges.

You might have to turn down the gas a wee bit running N540 near max pressure.

 

[rothgyr]

I wouldn’t dump Grendel just yet.

Also, something has been going on with powders I think because data for some of the common ones has changed noticeably. Especially 8208XBR.

I was recently considering going ARC over my current Grendel. I'll bite. What's up with 8208 XBR? I decided against ARC just based on the lack of good data for 8208 XBR and 107s (I have 3500 107s on the shelf and about 16 lbs of XBR on hand) and ordered a new Grendel barrel yesterday instead.

 

[stello1001]

The reason we all end up with so many powders is different barrels like different powders. You should probably get a load sorted and then when you know what shoots best buy more of that.

For Grendel based cartridges you can shoot anyone of:

TAC
8208
4895
Varget
CFE223
LeverRevolution
2520
StaBall

Which staball?

Staball HD, MATCH, or 6.5?

 

[danr]

I need to try LeveRevolution. I was pushing Varget/CFE at max loads (105/107s) that were over pressure in my AR arcs. I had to back the loads off to almost where my Grendel was performing well.

 

[rothgyr]

LVR is great for speed, but it's not super temp stable, and the ES numbers can get pretty big.

 

[Dogtown]

The weird thing about LVR: it seems to improve SD/ES the closer I get to max. I don't know why, but if I do mild charges between 26-28gr I get pretty big numbers, but when I start to approach 30gr they improve significantly. I may just be an outlier though.

 

[rothgyr]

The weird thing about LVR: it seems to improve SD/ES the closer I get to max. I don't know why, but if I do mild charges between 26-28gr I get pretty big numbers, but when I start to approach 30gr they improve significantly. I may just be an outlier though.

Interesting. I used it in a 6.5 Timberwolf (6.5 Dasher basically) back in the day and wasn't anywhere near max. That might explain the wild swings I got.

 

[LRRPF52]

I was recently considering going ARC over my current Grendel. I'll bite. What's up with 8208 XBR? I decided against ARC just based on the lack of good data for 8208 XBR and 107s (I have 3500 107s on the shelf and about 16 lbs of XBR on hand) and ordered a new Grendel barrel yesterday instead.

Charge weights and velocities from several years ago are different now that Hodgdon’s updated their data for Grendel. They used to have 40 published loads, then went to 170, now 135 for Grendel. Biggest changes were 8208XBR and the addition of CFE223 and LVR, which they didn’t have for years. Hornady was first to publish Grendel data with CFE223 and LVR, which were the fastest powders for 123-129gr.

Their data shows considerably-faster speeds with the same charge weights. Chamber pressures changed a lot too.

90gr TNT on 8208XBR used to be 31.0C max 2794fps at 42,400psi.

Now it’s 31.1gr max at 2992fps at 50,400psi.

That’s an 8,000psi jump at basically the same charge weight, with 200fps more mv.

For H335 under 90gr TNT, their charge weight dropped about a grain, velocity increased 80fps, pressure went up 1,000psi.

I’m not sure if powder formulations deviated during Wuhanflu or what, but there have been noticeable changes.

 

[LRRPF52]

Another reason why I collect as many sources for reloading data as possible and start at recommended start loads, run pressure ladders over a chrono to see the trend and any departure from the trend.

 

[rothgyr]

And another reason to buy one lot and not from several. I'm glad most of my stash is from the same lot, yikes.

 

[JR1200W3]

And another reason to buy one lot and not from several. I'm glad most of my stash is from the same lot, yikes.

Until you open it and it dries or draws in humidity

 

[Dogtown]

<sad_trombone>

 

[supercorndogs]

I prefer my arc to my grendel. I have also learned to prefer some of the slower ball powders for both of them with heavy bullets. Mp501 which is supposed to be around the 2520 area. Runs pretty close with three good ones. LVR, cfe223, and 2520. In my experience varget and 8208 are tougher on brass and probably tougher on the gun also. Unless it's for light bullets. My 6 arc liked 8208 with the 65 vmax. My gredel likes h335 with the 107smk.

 

[CaptNemo]

Add AR Comp to your list if you can find it / afford it...

 

[JR1200W3]

Add AR Comp to your list if you can find it / afford it...

Is it fast enough?

I also heard a rumor that alliant powders was going to suspend commercial distribution for the foreseeable future. I don't know that I would try to get hooked on meth if meth was going to go away.

 

[supercorndogs]

Is a powder made for 223 fast enough.
Yes. It is on the little faster than needs to be side even I bet.

 

[JR1200W3]

Is a powder made for 223 fast enough.
Yes. It is on the little faster than needs to be side even I bet.

A yes would do. You don't have to be a cunt about it.

 

[memilanuk]

Anyone tried 2000MR in this behind the heavier projectiles? I've got about 16 pounds of the stuff, so availability isn't an issue for a while

 

[LRRPF52]

Is a powder made for 223 fast enough.
Yes. It is on the little faster than needs to be side even I bet.

All of the powders listed by Hornady for 6mm ARC are common to .223 Rem.

The faster-burning ones are for lighter bullets, and the medium-burning powders are for 90-110gr.

 

[Dogtown]

The faster-burning ones are for lighter bullets, and the medium-burning powders are for 90-110gr.

^^^ 100%

 

[LRRPF52]

Anyone tried 2000MR in this behind the heavier projectiles? I've got about 16 pounds of the stuff, so availability isn't an issue for a while

Hornady lists Power Pro 2000MR data for everything from the 90gr GMX to the 110gr A-TIP.

 

[DeathBeforeDismount]

Until you open it and it dries or draws in humidity

Take all your powder, dump into a container, stir it up and then put back in Jugs. Now your lots are normalized. Most powder is around 50% when stored so depending on your climate (One of the reasons to reloading in a climate controlled space, to keep humidity bellow 40%) you will have consistent powder and now have to worry about as much variance.

 

[Dogtown]

Take all your powder, dump into a container, stir it up and then put back in Jugs. Now your lots are normalized.

I know that is technically sound, but it sure feels sketchy

 

[supercorndogs]

All of the powders listed by Hornady for 6mm ARC are common to .223 Rem.

The faster-burning ones are for lighter bullets, and the medium-burning powders are for 90-110gr.

Yes.

This thread is about powder for heavy bullets.

 

[LRRPF52]

I know that is technically sound, but it sure feels sketchy

There are smooth brains who will read that and literally consider taking ALL of their powder types, dumping them into a large container, blend all the extruded, flake, and ball propellants into a smorgasbord, then redistribute it back into the cans.

 

[DeathBeforeDismount]

I got into some lot issues at a recent match. I came home, took 5 jugs of H4350 with 3 different lots, dumped into a big ass bin. Mixed it up real well, then poured back into the jugs and labeled them all.

 

[LRRPF52]

IMR 8208XBR seems to have taken a significant turn in energy with more recent lots, so you definitely can’t rely on your old data with it.

 

[memilanuk]

Hornady lists Power Pro 2000MR data for everything from the 90gr GMX to the 110gr A-TIP.

Yeah... but I don't see many (any) real-world range reports with it, which is why I asked

 

[DeathBeforeDismount]

IMR 8208XBR seems to have taken a significant turn in energy with more recent lots, so you definitely can’t rely on your old data with it.

I would love to find some. Haven't seen it in almost 4 years now. I am using TAC in a dillon 750 since it meters well, but its hellacious ES means I need to find something else. 8208 would be perfect, meters well, temp stable, very good powder. Its just unobtainable.

 

[Shoots 700's]

AR-COMP should work, its great in the 6.5 grendel with 123's

 

[stello1001]

AR-COMP should work, its great in the 6.5 grendel with 123's

Let us know if you find any

 

[Shoots 700's]

Lucky I have some

Anyone try N135?

 

[Ape_Factory]

IMR 8208XBR seems to have taken a significant turn in energy with more recent lots, so you definitely can’t rely on your old data with it.

I concur. Was very disappointed with its performance in both velocity and accuracy. TAC and VV550 kicked its ass with 77gr. in 223., two different barrel lengths.

 

[MarshallDodge]

Lucky I have some

Anyone try N135?

How about N133?

Rumor has it does well in 6ARC

 

[Yondering]

The weird thing about LVR: it seems to improve SD/ES the closer I get to max. I don't know why, but if I do mild charges between 26-28gr I get pretty big numbers, but when I start to approach 30gr they improve significantly. I may just be an outlier though.

This is very true, definitely not just an outlier. I've been saying this here for years now - Lever burns cleanest and gives the smallest SD when run right up to max. If you're going to use Lever, load it near max. If you want mild loads, there are other powders that work better for that.

In most situations near max is where Lever gives the best accuracy as well. That's what makes it such a great powder for high velocity loads - it's super easy to load with if you follow basic load development practices and a couple peculiarities*, and you won't find another powder capable of more velocity safely, within the appropriate applications of course. CFE223 was mentioned earlier - it comes close to Lever's velocity, but is not as forgiving at max pressure and often doesn't exhibit the same trend in SD and accuracy.

The main peculiarity of Lever is that it makes a LOT of gas, so adjustment of an AR's gas system is mandatory. The people who claim it's really dirty or gives high SD are often the people who didn't adjust their gas system, and had to stop at a lower pressure charge because they're seeing false pressure signs due to early unlocking. Restrict the gas a little more and you'll see those false pressure signs go away. A heavy buffer is not enough.

The other peculiarity is that in my own testing, it's proven to be temp sensitive in a linear fashion down to about freezing temps, and then flattens out below that. I typically develop a summer load and a winter load with Lever for the year-round cartridges; others are only used seasonally so no need. If you want a temp stable powder for 6 ARC, then 8208 is the best bet but good luck finding it right now, and you'll give up velocity in the small 6 ARC case compared to Lever.

Also for the OP - if you're getting rid of the Grendel to reduce the number of powders, don't. The Grendel and 6 ARC share a lot of the same powders, including Lever as the top velocity performer for both with mid-heavy bullet weights.

I use Lever in a wide range of cartridges; most of these don't have published data for them but if you're comfortable with load development, the results don't lie. Here's what I use Lever for:

20 Tactical
223 / 5.56 (69gr+)
6mm-223
6mm ARC / 6mm Grendel wildcats
6.5 Grendel
6.8 SPC
30/30
308 / 7.62x51
35 Remington
35 Whelen

 

[gopherslayer]

I have Lever on the way along with Benchmark for 223 which I already use quite a bit of. I could also find Lever locally during this last 4 years of bullshit. Benchmark was sporadic and expensive. Now to bite the bullet and round up components and a 6 arc barrel and 223 7 twist for a bolt gun.

 

[Gtscotty]

My favorite for my Grendel was ARComp, with 8208 as a second. I haven't tried either in my 6 ARCs, figured they'd be too fast for decent velocity with the heavies and the load data seems to back that up.

For my ARCs, I really like LVR, it's usually available, gives top velocities with the 80gr and up bullets I've used, and excellent accuracy. It isn't temp stable, but I haven't had major issues from that yet. I have burned some Staball Match in the ARC and it does well too, gives up some velocity to LVR though, which I guess is to be expected since it's in the faster Varget burn rate range.

LVR in my hunting loads loads for my LW 18" hunting ARC: (that ~29.3gr load range has has worked very well with several different bullets 100gr to 108gr, seems to be a sweet spot)

 

[LRRPF52]

I would love to find some. Haven't seen it in almost 4 years now. I am using TAC in a dillon 750 since it meters well, but its hellacious ES means I need to find something else. 8208 would be perfect, meters well, temp stable, very good powder. Its just unobtainable.

My local grocery store had several kegs of it a few months ago, and I just kept walking by them day-after-day, then they disappeared once I posted about it on my local group.

 

[rothgyr]

How temp stable is LVR? I see a lot of it here and there. So long as it's fairly predictable, it might be worth stocking up on, and adjusting for temperatures.