6mm Arc Best bullt/powder combos for 600+

[gunsandgunsmithing]

Being the idiot that I am, I have to test. My use is field use and after I work the load the best that I can at the range I take it to the field and test more. At the range we get predictable winds because the wooded area has not changed in 5 decades, nor has the open areas so the variations in the wind are limited and my knowledge of how it reacts from the firing line to the target is extensive. In the field things are catch as catch can, I don't always have significant knowledge of how the lay of the land affects the projectile. This type of study helps me pick the final load better, terraced fields may have many eddy currents and hyper velocity can help.

Not having any idea (nor caring) why but my 223 and my 6MM Remington both produce very good 100-yard groups with light to medium weight bullets for the caliber. With that said I see it as an advantage as the vast increase in velocity, (500 to 600 FPS more) that I can get with a 40-grain vs a 60+ grain projectile is amazing. Similar can be said for my 6MM Remington with a 75-grain vs 100+ grain projectiles. What I have found is that the reduced time of flight helps reduce longer range group size as the wind speed increases.

On easy days the 223 is very effective out to 350 yards, on very calm days I have taken shots and made solid hits out past 400 yards. As the wind goes up, I move on to the 6MM Remington, which is very effective in moderate winds out past 400 yards, I've made hits out to 600+ yards. I'm not sitting there in a field and taking 3 or more shots at a chuck, my old man would crawl out of his grave and choke me.

The advantage I see for the field is not only better groups in wind but a reduced arc in the trajectory which helps with range estimations. The higher velocity is advantageous with wind eddy currents that run through the gullies in a terraced field. I'll take a 1/8" bigger low wind 300-yard group if the same load produces a 1 1/2" smaller group in higher wind.

The disadvantage is that I have good reason to suspect (via testing) that both of these rifles can produce better on range groups at long range with heavier projectiles if I can get some experience with the wind at the range and dope it well.

Flatter is much better at modest ranges in the field. Asa to the better long range groups with heavies...I'd test that thoroughly. In good wind and/or good wind calls, I'll take accuracy every time. If yours truly shoots heavies better or even almost, I may well go with them. The thing I see a lot is that people thoroughly test what they want to work and don't always test the other stuff enough to find all the potential it might have. I'd go so far as to say that better than 90% of the time, in good wind out to at least 600, the lighter mid weights will actually outshoot the heavies. But ya just gotta test to know and that's part of the fun. If all rounds are fired in the same good condition, it's about ultimate accuracy. Reality is, they don't all get fired in exactly the same condition and that's when bc may help more.

 

[David Milisock]

Flatter is much better at modest ranges in the field. Asa to the better long range groups with heavies...I'd test that thoroughly. In good wind and/or good wind calls, I'll take accuracy every time. If yours truly shoots heavies better or even almost, I may well go with them. The thing I see a lot is that people thoroughly test what they want to work and don't always test the other stuff enough to find all the potential it might have. I'd go so far as to say that better than 90% of the time, in good wind out to at least 600, the lighter mid weights will actually outshoot the heavies. But ya just gotta test to know and that's part of the fun. If all rounds are fired in the same good condition, it's about ultimate accuracy. Reality is, they don't all get fired in exactly the same condition and that's when bc may help more.

My old school brain figures that the functional range needs to be my limit. I don't shoot at man sized targets and there's no way I'm popping off chucks at 1,000 yards. Reality is I won't take a shot unless I figure I can make a one shot kill, so my rifles are capable out to ranges that I can see a ground hog well enough to hit.

 

[Park ranger]

I’m playing with the 6 ARC now. 28.1 grains of AA2520 with 108 ELDM and 109 Berger Hybrid. Getting 2600 FPS with a 22” barrel. I figure max pressure in the AR. 2.0 moa at 600 yards- 25 shots with the 108 and 1.5 moa with the 109 berger -10 shots.

Anyone try the 105 hybrid in the 6 arc?

 

[DHD]

I’m playing with the 6 ARC now. 28.1 grains of AA2520 with 108 ELDM and 109 Berger Hybrid. Getting 2600 FPS with a 22” barrel. I figure max pressure in the AR. 2.0 moa at 600 yards- 25 shots with the 108 and 1.5 moa with the 109 berger -10 shots.

Anyone try the 105 hybrid in the 6 arc?

I haven't but my shooting partner has. He loads them with Varget using the Hornady data for gas guns very near the maximum listed charge. Velocity is what I would consider low but the accuracy is what we consider stellar. As he has a lot of up left in the scope I suppose he can always twist the knob (we only have 600 yards so....).

I'm brand new to the ARC but been with the Grendel since 2009ish and can appreciate what Mike is saying about the light to midweight bullets in certain lower capacity cases. I am set up with quite a few of the big yellow and green boxes of 6mm 105-108 bullets but when I jumped into the ARC, I purchased 95 grain bullets (SMK's, VLD's, and Classic Hunter) to keep the velocity up. So far that choice has worked out well.

 

[Ledd Slinger]

Tagging in because I have an 18" 6ARC 8" twist upper coming for a new AR build. I have a bunch of 100gr Sierra Tipped Game King bullets I plan to try. If that doesn't work I have a lot of other 6mm bullet options on the shelf. Also have a bunch of Lapua 6.5 Grendel brass to neck down and play with.

 

[DHD]

I see the 100 grain TGK mentioned as a good accuracy bullet on some other forums. The 90 grain version is mentioned also. Specifically talking about in the 6mm ARC.

I'm focusing on 95 grain bullets, at least initially, in mine. If I could find any of the 90/100 grain TGK's I would definitely throw them in too. They will come back around soon I suppose. My rifle is loving the 95 grain SMK and I might not be able to improve on them.