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Discussion Starter #1
Hi,

I'm still doing load development, but I went out with some Berger 185gr Juggernauts today and my SCAR. I was using Varget, Winchester brass, and Wolf primers. Just doing OCW at this point, but I was able to print a CTC max spread of 0.480" group without any tuning of seating depth. I'll take pictures/post load information when I'm done with load development, but just wanted to let folks know these will stabilize in our barrels. I was shooting suppressed after determining they were not yawing. Velocity on my 'max' load of 44.1gr of Varget was 2395FPS (average). That puts estimated pressure at 58862PSI in Quickload, with burn rate adjusted to match velocity measured at muzzle via a Magnetospeed.

My OCW development looks like it's going to land me around 42.9gr (2329 FPS if Quickload is accurate - I was not measuring velocity of everything I shot as the Magnetospeed slightly alters POI) which will stay supersonic to about 900 yards, then shift trans-sonic. The great thing about the Juggernaut as it's called - it stays relatively stable through this transition. I'll work on dope charts once I get the seating depth dialed in for great groups, and then take some velocity measurements.

In case people are wondering why I went with such a heavy bullet in the SCAR - I hate windage. This bullet has an extremely high BC and doesn't tend to get tossed around much. Coupled with the ability to go trans-sonic without major effects, and maintaining about 500ft/lbs at 1000yds (1107fps at that point) this should be a nice round for all kinds of distances.
 

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That is having your cake and eating it to! Keep us posted please.
 

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You should get a lb of Alliant Power Pro 2000MR and try it with those 185s. I was able to push 150 gr FMJ to 2700 fps out of my SCAR 17 with 51 gr of it and once-fired black hills match cases (~Winchester), and it supposedly performs even better with the heavier bullets.
 

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Discussion Starter #4 (Edited)
Finished doing work with these, on average I was able to get around 1MOA. I'd have 3 shots in .50-.75" and then two that were at 1". This is across a _lot_ of 5-shot groups, as sometimes I'd get 1/2" groups and sometimes not (hence the initial promising results). I'm going to work on some 168gr A-Max loads and see if I can tame the scatter shots. If I can, I'll stick to the lighter weight bullets because I don't need 1000yds out of this rifle. If I can't, then I'll work on further optimizing these loads. As I was tweaking seating depths, I was able to tighten things up a bit, but I didn't spend a lot of time on it, because I wanted something that was reliably under 1 MOA without close tolerances and excessive time spent reloading each round/powder/temp/etc sensitivity.

FWIW, I was able to easily hit 2350fps without pressure issues. Note to FN: The 1:12 twist is non-optimal. At least go with a 1:11, so it can shoot the 150/147gr stuff fine, but also handle bullets with a longer bearing surface. Even the 178gr A-Max would be nice (and it shoots fine) but the twist just doesn't do it justice. With a short barrel, and the 1:12 twist, I'm finding you need 168gr or less for optimal grouping, which is unfortunate. I'm hoping with the 168gr I can hit the second node for velocity/barrel timing but it'll be at the higher end of safe pressure. This reminds me of the 1:9 vs. 1:7 twist re: .223/5.56. Lots of people stuck with 1:9 for a long while, but gradually the manufacturers have shifted to 1:7, which is far superior for just about any usage.
 

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You might want to look into Nosler 168gr Custom Competition bullets. The perform well in the 17 and I got 2 nodes without any pressure signs. I also had success with the 168 Amax but just don't like the poly tip even though I've shot 1,000's of them through a bolt gun.
 
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