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Quest for a Sub-MOA AR-10 in 308

conditionzero

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I loaded up 5 sets of 7 rounds in powder charge ranges that I knew were at the FPS that I wanted. I overlayed all of the shots to see which were grouping together horizontally, that way I can work on fixing ES/SD and tighten up the groups.

Load #2 is 42gn of Benchmark and #3 is 42.1gn. This was the first time I have done a 0.1gn spread, I usually do 0.2gn but wanted to try something new. Each group had a flier, I am not too worried about those.

Being a semi-auto gas gun I don't have a lot of room for tuning but I am hoping I can pull in the #3 load to be consistently under 1 MOA.

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EC tuner can help with that. I put one on my 6.5 CM gas gun. Going to load some rounds after testing today. My D.A. loaded some round the same length as my bolt. Going to load some more to AR mag length.
 
After some vary basic load development and a EC tuner brake. I got sub MOA out of my 6.5 CM AR10. Going to work on SD and ES to fine tune the load for this rifle. Setting 2 on the tuner looks like it worked the best.
 

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Awesome! So far I am pretty consistent with 42.1gn of benchmark. I might step down to an 18" barrel on this gun but we will see.
 
What load were you using to ring that steel @1000 last month?
 
i dont know off hand. I want to say the same powder charge as the bolt. I know it’s a different set back. I do remember sd and es was a lot wider range.
 
What load were you using to ring that steel @1000 last month?
42.1gn of benchmark. I am going to revisit after a couple upgrades. I also just changed the brake so I will see what happens. Hopefully next week isn't so damn cold.
 
Watch “Johnny’s Reloading Bench” on youtube. He pulls it off several times with several loads.
 
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Sorry. Johnny’s. Not Steve’s
 
Which AR-10 are you using on this quest?
 
A while back I bought a Falkor Defense upper that has a Proof Research carbon fiber wrapped SS barrel and put it on a DPMS lower that I already had. Took the time to break it in as per mfg. instructions. I have been getting 2" groups with AE 168 gr OTM which I consider 2nd tier ammo. Guess I'll have to give some of that top dollar stuff a try and see if the groups shrink up enough to justify the expense.
 
A while back I bought a Falkor Defense upper that has a Proof Research carbon fiber wrapped SS barrel and put it on a DPMS lower that I already had. Took the time to break it in as per mfg. instructions. I have been getting 2" groups with AE 168 gr OTM which I consider 2nd tier ammo. Guess I'll have to give some of that top dollar stuff a try and see if the groups shrink up enough to justify the expense.
Hornady ELDM or Federal GM would be where I'd start. It's usually not too spensive and stocked.
 
Wow, Tripod, and Bipod, do you also have the obligatory bench attachment?

It does seem to have all the equipment to get to sub MOA. If your not reloading I think RockChalks suggestion is sound or some M118 LR.
 
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