Try a Matchking bullet 175gn HPBT 43.5gn varget at a 2.222 COAL using Ogive. That's a solid load.
- Thread starter kaskin
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44.2 looks good to me. I'd stop messing with it and shoot.
My barrel is a 1:12 so I tried to stick with a lighter bullet.
I believe I’m going to stop looking and shoot for a while. See what happens.
Thanks to all..
I believe I’m going to stop looking and shoot for a while. See what happens.
Thanks to all..
D
Deleted member 113831
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In all your testing, There is a consistent major POI shift at around 43.3 grains. This indicates that this is the beginning of the optimal pressure range.
This range has consistently extended to 44.8 grains, where there is another major POI shift. This is where you get into your high pressure.
On your graph, you show a flat spot at 44.2 grains. Not only is this right in the middle of your optimal pressure, but it is in the immediate neighborhood with the thousands of rounds of this load that I, and others have shot over the years.
Any of these loads can be tweaked with seating depth to tighten them up. OCW is not about groups, or even "flat spots", It is about determining optimal pressure ranges by watching for major POI changes.
I would stick to within 0.3 grains of either side of 44.2 grains, and tweak seating depth in .005" increments from 2.810" down to 2.795". if your rifle won't shoot something in this little window well....then it isn't the load.
Every 308 is going to have a node around 42.3-42.7 then another around 44.0-44.4 then another around 46.0-46.3 Your testing shows the same thing. 308 load development should take no more than 40 rounds from start to finish depending on what node you want to run.
D
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The middle and high range are most often 0.5 grains less on each end when using heavy brass, like LC, Lapua, or Federal.
So, 43.5 - 44.0 and right around 45.5 with 175 grain bullets. The high node is a brass destroyer though, and a fickle bitch to boot!
My Rem 700 24" heavy barrel .308 shot 44-45gn Varget loads best. Especially 44.2 From your initial charts targets 5 and 11 seem to be the ones that stand out by the 'eye test'. 11 maybe somewhere to look at changing your bullet seating depth to tune it. However I'm going to look for consistency at 44.2gn as this is my finding as well.
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I have learned a great deal from this thread.
How accurate can I get my battle rifle?
I am interested in the translation of this info to my Patriot Ordnance Factory AR-10 308, 18" fluted barrel, muzzle brake, 1:10 twist, 2.8 COAL from a PMAG, Magpul PRS stock.
I have 165, 168, 175, 180, 185, 190 projectiles and IMR 4064 and Varget powder. I also have Lapua never fired brass.
Has this been tackled yet? If so, I haven't found it yet.
How accurate can I get my battle rifle?
I am interested in the translation of this info to my Patriot Ordnance Factory AR-10 308, 18" fluted barrel, muzzle brake, 1:10 twist, 2.8 COAL from a PMAG, Magpul PRS stock.
I have 165, 168, 175, 180, 185, 190 projectiles and IMR 4064 and Varget powder. I also have Lapua never fired brass.
Has this been tackled yet? If so, I haven't found it yet.
