6mm AR15 cartridge options

[PNW_Steve]

I am following this with great interest. I set out on the mission to build a nice AR-10 in. 243 Winchester.

Well thing got suddenly more complicated when I actually shot an AR-10 with a heavy profile. Bench.... Good, Prone..... Good, Offhand..... Not in this lifetime.

Now I am shopping AR-15 6mm cartridges. I have a new favorite every 30 minutes. The temptation to just pick one and run with it is manifesting itself.

I was gung ho on. 243lbc then I saw the Fat Rat, then found out about the 6 arc and .24 Nosler that are both SAAMI accepted.

I got to looking hard at " 6 Grendel" then I talked to John at White Oak and he made some good points about cases based on a smaller bolt face for reliability and longevity. That got me seriously looking at the 6 woa.

I am also considering rebarreling one of my bolt guns in whatever 6mm I pick.

 

[steve123]

I don't shoot my 6mmFatRat much, maybe 3-4 outings since my last post, but it's impressive how well it does with those 95's at 2870 fps compared to my 6mmBR with 105 hybrids at 2904 fps. The 6mmBR bolt rifle is definitely easier to shoot and more precise but on 1.5 moa steel the windage isn't much different at 800Y, though by 1000Y I can tell a difference.

It's fun shooting the FatRat with fast follow ups! I can rattle off another shot as soon as I see where the previous shot hit! Last time out at 1000Y I peppered up a 19" steel using 1.5-2.2 mils of holdoff in bad winds from 3 oclock. My friends with 30-06 and 6.5 PRC bolt rifles couldn't shoot fast enough to get as many hits as I could because the wind kept fluctuating so much. My vertical was small-ish too. Part of the reason for my success is I was able to learn quickly where a bullet went in a gust and in a lull whereas the other guys couldn't make sense of the whole wind temperament.

 

[steve123]

I am following this with great interest. I set out on the mission to build a nice AR-10 in. 243 Winchester.

Well thing got suddenly more complicated when I actually shot an AR-10 with a heavy profile. Bench.... Good, Prone..... Good, Offhand..... Not in this lifetime.

Now I am shopping AR-15 6mm cartridges. I have a new favorite every 30 minutes. The temptation to just pick one and run with it is manifesting itself.

I was gung ho on. 243lbc then I saw the Fat Rat, then found out about the 6 arc and .24 Nosler that are both SAAMI accepted.

I got to looking hard at " 6 Grendel" then I talked to John at White Oak and he made some good points about cases based on a smaller bolt face for reliability and longevity. That got me seriously looking at the 6 woa.

I am also considering rebarreling one of my bolt guns in whatever 6mm I pick.

Pretty much my opinion but...

The reason I ended up with my 6mmART40 at the time was that my DPMS 243 had quite a bit more felt recoil from the heavy BCG . I didn't like the extra weight of the gun either. Previous to the 243 I had a DPMS 308 and between both those two large frames I decided large frames weren't for me so I never bought another. Though I imagine a JP 6.5 Creed would be awesome but out of my price range.

I keep forgetting to mention 22 PPC. Good quality factory brass with more oomph than 223AI and short enough for heavies in a AR. 95SMK/.6BC at 2700 fps would be fantastic! I'm surprised we don't hear about this cartridge much??? Somebody build one!

 

[PNW_Steve]

Pretty much my opinion but...

The reason I ended up with my 6mmART40 at the time was that my DPMS 243 had quite a bit more felt recoil from the heavy BCG . I didn't like the extra weight of the gun either. Previous to the 243 I had a DPMS 308 and between both those two large frames I decided large frames weren't for me so I never bought another. Though I imagine a JP 6.5 Creed would be awesome but out of my price range.

I keep forgetting to mention 22 PPC. Good quality factory brass with more oomph than 223AI and short enough for heavies in a AR. 95SMK/.6BC at 2700 fps would be fantastic! I'm surprised we don't hear about this cartridge much??? Somebody build one!

Yeah, the AR-10 was a fun idea and I may still pursue it one day. The AR-15 is simply more practical. Many more convenient opportunities to shoot it. Going with .243 instead of .224 means that I can hunt with it and hopefully, compared to .224 Valkyrie, have a little longer brass and barrel life.

According to Fish and Game, you cannot responsibly kill a deer with. .224. I don't entirely agree.......

 

[sam4886]

I built my 6 predator a couple years ago before the ARC was around, but if I were doing it now....the factory support sure is nice.

I haven't seem much about the arc besides the thread here somewhere, so I don't know about time pines for release, but that's the way I would go.

Wildcats are fun, and reloading is OK, but shooting is better.