Anyone loading for the 6mmAR?

[Dusty Stevens]

What range of charge weight did you use for 8208 and the 95 SMK's? I have a fat rat, and i'm having a hard time with the 95SMK/H4895 combo. Is yours a 6mmAR or the Turbo?

I doubt 8208 is the best powder for that heavy of a bullet. You can use h322 data if you start a tad lower and work up. 8208 would be the ticket for 62-65gr bullets but my exp you need to be in the n135 range to have the best load. Look on a burn rate chart for similar powders

 

[HomeSlice]

I doubt 8208 is the best powder for that heavy of a bullet. You can use h322 data if you start a tad lower and work up. 8208 would be the ticket for 62-65gr bullets but my exp you need to be in the n135 range to have the best load. Look on a burn rate chart for similar powders

Thanks for the tip!

 

[Damon555]

One observation that I've made is that the load data on the 6mmAR site seems to be on the hot side. I've not been able to even get close to the max loads listed there before I run into significant pressure signs. I guess my chamber could be slightly different. It's not really a problem though....accuracy trumps speed in my opinion....as long as the velocity isn't unreasonably low.

 

[gunsandgunsmithing]

One observation that I've made is that the load data on the 6mmAR site seems to be on the hot side. I've not been able to even get close to the max loads listed there before I run into significant pressure signs. I guess my chamber could be slightly different. It's not really a problem though....accuracy trumps speed in my opinion....as long as the velocity isn't unreasonably low.

Are you shooting a bolt gun or AR? His data, I believe, is all based on AR15 rifles. I've found his data significantly lower than I can go in a good bolt gun. FWIW.

 

[Damon555]

It's an AR15.....that's what made me wonder why I was hitting pressure signs so early compared to their rifles....Should be pretty close to the same setup. But I know pressure signs when I see them and they are pretty obvious....I'm already getting it figured out though and am pretty happy with what I'm seeing......just playing it safe....no reason to get hurt trying to make the gun into something that it isn't.

 

[Dusty Stevens]

It's an AR15.....that's what made me wonder why I was hitting pressure signs so early compared to their rifles....Should be pretty close to the same setup. But I know pressure signs when I see them and they are pretty obvious....I'm already getting it figured out though and am pretty happy with what I'm seeing......just playing it safe....no reason to get hurt trying to make the gun into something that it isn't.

see if you can adjust your dwell time and gas. on these hi perf cases you have to pretty much redesign the gas system

 

[Ksmirk]

I've gotten busy with work and haven't gathered a mess of info yet but like the others have mentioned 8208 might not be the ticket for the 95's. I've got the 243LBC chambered in a bolt rifle and AR and from what I've found the AR I drop back right about 1 grain or you can measure you bolt dims from the brass lol

I'm hoping things slow down a touch so I can get back to work on these two rifles and really get some good info I can pass on as I think this little round has a mess of potential!

 

[gunsandgunsmithing]

I've gotten busy with work and haven't gathered a mess of info yet but like the others have mentioned 8208 might not be the ticket for the 95's. I've got the 243LBC chambered in a bolt rifle and AR and from what I've found the AR I drop back right about 1 grain or you can measure you bolt dims from the brass lol

I'm hoping things slow down a touch so I can get back to work on these two rifles and really get some good info I can pass on as I think this little round has a mess of potential!

Me too! It definitely has a lot of potential. What's not to like? It has pretty much all I can ask for going for it.

 

[Damon555]

see if you can adjust your dwell time and gas. on these hi perf cases you have to pretty much redesign the gas system

That was my next thought too Dusty. There might be an adjustable gas block in my future.

Me too! It definitely has a lot of potential. What's not to like? It has pretty much all I can ask for going for it.

Me thinks that we are fiddling with the next big thing in the AR world as far as accuracy is concerned. I might not hit its full potential just because there comes a point where I'm happy from a varmint hunters standpoint but bench rest shooters will no doubt push the accuracy limits of the little round.

 

[Richard Coody]

lots of potential in that grendel case

http://forum.accurateshooter.com/threads/6mm-grinch-defeats-entire-field-of-6ppcs.3912901/

http://bulletin.accurateshooter.com/2014/06/now-thats-accuracy-mike-ezells-tack-driving-30-major/

 

[newbieshooter]

I used to shoot the 6mmAR T40 at our club VFS matches. Running 28.2gr H4895 + Berger 105 Hybrids (single loaded). Seating depth tests would yield 3 shot groups:

 

[gunsandgunsmithing]

I used to shoot the 6mmAR T40 at our club VFS matches. Running 28.2gr H4895 + Berger 105 Hybrids (single loaded). Seating depth tests would yield 3 shot groups:

View attachment 1049168 View attachment 1049169

Back when IBS passed and sorta tried to promote an ar15 class, I had a couple of AR's that I had built just for that game, IBS VFS. I had chambered them in my 30 Major, a 30 Grendel, that I still campaign in BR matches regularly, in a dedicated bolt action Borden BR rifle. Why not? It's the same cartridge that owns the record for smallest 5 shot group ever fired at 100 yards! They shot extremely well as AR15's and were the best thing at the time...and probably still is, for an IBS/NBRSA VFS target, for an AR specific class. It's amazing how well a 17 or 18 twist 24" 30 BR barrel will look and shoot after cutting it down to about 18" and contouring it for it for an AR. I still have an upper and I plan to hunt deer with it one day but if an AR15 specific class ever gets revived, I'm pretty well set for it with one of those. I shot 110-125 gr bullets at about 2,650fps. It will shoot bugholes. I still want to try double taps on a whitetail with Nosler 125 BT's at a moderate distance with it.
I've built them for other hunters that say it's an awesome deer rifle for woods hunting or within about 300 yards. I think all of them that I've done with top quality barrels have been honest .3" AR15's. Not bad for a gas gun with some uumph! In 3-gun matches, it was a blast to shoot steel with against 223/5.56 guns. A hit that you could barely hear with a 223 would send the plate flying with the 30.

 

[Damon555]

Another quirk that I've noticed with my upper, which is an 8 twist, is that it seems to prefer the heavy bullets along with pills on the lighter end of the spectrum. Is it unusual for a certain barrel to exhibit a propensity for the extremes?

 

[HomeSlice]

I have a fat rat with a 7twist. It’s a lot like the 6mm turbo 40.

It absolutely loved the new Sierra 110s. It does ok with the 87 hornady. Struggling to get decent groups with the 95 smk.

 

[CT10ring]

i don’t have access to load data,
but had good results w vv n135 & H335 both
& 75g vmax, cci br4’s. my 6AR used for
varmint shooting only. 8 twist hart bbl
sabreco 26” bbl.

 

[steve123]

I have a fat rat with a 7twist. It’s a lot like the 6mm turbo 40.

It absolutely loved the new Sierra 110s. It does ok with the 87 hornady. Struggling to get decent groups with the 95 smk.

You must have been single loading in your AR for the 110 SMK or is your Fatrat a bolt rifle?

Most rifles shoot the 105 hybrid well, my Fatrat just didn't like them and the load was a very compressed load.

When I went to the 95 SMK there was an immediate difference in groups, basically solid 3/4" groups which I was happy with for a cheap Wilson barrel.

 

[HomeSlice]

You must have been single loading in your AR for the 110 SMK or is your Fatrat a bolt rifle?

Most rifles shoot the 105 hybrid well, my Fatrat just didn't like them and the load was a very compressed load.

When I went to the 95 SMK there was an immediate difference in groups, basically solid 3/4" groups which I was happy with for a cheap Wilson barrel.

Yep, I single load the 110s for 600. It's a spagegun upper. I can't get the 95s under 1.5" @100 to save me, though. Care to share your load?

 

[Damon555]

i don’t have access to load data,
but had good results w vv n135 & H335 both
& 75g vmax, cci br4’s. my 6AR used for
varmint shooting only. 8 twist hart bbl
sabreco 26” bbl.

Hmmmm......we've got the same upper.....no wonder the performance is similar.

 

[gunsandgunsmithing]

You must have been single loading in your AR for the 110 SMK or is your Fatrat a bolt rifle?

Most rifles shoot the 105 hybrid well, my Fatrat just didn't like them and the load was a very compressed load.

When I went to the 95 SMK there was an immediate difference in groups, basically solid 3/4" groups which I was happy with for a cheap Wilson barrel.

I've seen some very good Wilson barrels. Not that I would put them in the same category as a premium barrel day in and day out, but they really aren't bad. I think they all get luck every once in a while. Just like top shooters, if you're good, you get lucky a lot! Cooper uses Wilson and the old Winchester m70 Heavy Varminters were Wilson barrels. Those are two of the best shooting factory rifles ever made, IMO.

 

[steve123]

Yep, I single load the 110s for 600. It's a spagegun upper. I can't get the 95s under 1.5" @100 to save me, though. Care to share your load?

Sure, it's 95 SMK, 29.4gr H4895 with CCI450's in lapua formed brass. AOCL of 2.245". 2870 fps in my 22" 8 twist barrel.