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Discussion Starter #1
Ok guys, here's a RR on the load I just worked up:
Gun: SCAR 17 w/ 16" 1:12 twist, .308 barrel
Bullet: Factory 2nd Nosler Custom Competition 168 gr HPBT w/ cannelure (yes, they made these once and I bought 5k from a guy on EE at ar15.com).
Brass: 1994 Lake City Match
Primer: Wolf LR
Powder: Alliant Power Pro 2000 MR
All bullets held in place with LFCD at the cannelure leaving a C.O.A.L. of 2.770"
Conditions: first 50 rd test were calm and 75 deg F, today was VERY WINDY (25 mph from east) and 68 deg F. ~20% humidity both days.
Shot at 100 yd line at 2500 ft elevation.
I sorted 400 pieces of once-reloaded brass to get 105 pieces trimmed exactly to 1.995" (for X-Die sizing later, these typically range 1.993-1.997" from my trimmer) and sorted again for brass weighing between 177-178 gr (lake city match varies from 176.2-179.4 gr).
Next, I loaded up 50 rounds in 5 shot increments starting at 40.5 gr and increasing the charge by 0.5 gr until I reached 45 gr; this is the typical 10%x10% reduction from starting load due to military brass. Of these first 50 rds, I believe I found a node at 40.5 gr; at this charge level I was observing low pressure effects on the primer and my rifle would not cycle on the suppressor gas setting I usually run with slower powders (no suppressor on this gun).

As I observed zero pressure signs at 45 gr, I decided to work up another batch today and worked up in 0.3 gr and 0.2 gr increments until I reached a compressed charge of 47.6 gr (50.0 gr is max in commercial brass...).
Something magical happens with this powder as you approach maximum charge, everything tightens up!
45.3-46.4 gr:

46.8-47.6 gr (wind took my 46.6 gr target...):

47.4 gr isn't compressed (can still hear/feel powder when shaken) and looks like the best load. No primer issues, cases intact, etc. The compressed 47.6 gr load produced a peculiar smell, more flash and I suspect shouldn't be used in a carbine length barrel (maybe better in 20-24"?). Moving forward, I will load up another 100 rds with .1 gr increments from 47.2 to 47.5 gr just to see what exact charge to use; I have enough materials to make 5,000 of these...

I'll see about setting up my Chrony for the next 100 and update with MV, SD and ES figures. Will also test again at 90 deg F, 100 deg F and 110 deg F to see how temperature sensitive 2000MR is. Others have reported less than 1 ft/s/degF increase. Varget is like 0.3 ft/s/degF for comparison.
ETA: I'd also like to note that this powder burns slow, so I switched the gas regulator on my SCAR to suppressed mode at the start and 40.5 gr barely cycled the action. This produced a recoil below that I've experienced with standard 168 gr Nosler Custom Competition Match ammo with the standard gas setting. Should reduce wear and tear on the action too.
Does anyone have QuickLoad that could run the 47.4 gr load?

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Looks like you do a thorough work up! Thanks for sharing! :?
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