Sub-moa .243 hunting load out to 600yds

[BringBackThe80s]

Last summer I worked up a load in my completely stock Ruger American (1st Gen) compact/youth rifle. H4350 and 90gn Hornady CX at ~3080 fps from an 18", 1:9 twist barrel has kept 10-shot groups inside of 1" from summer temps of 85F down to 20F this winter. It has a pencil-thin barrel, so keeping it sub-MOA above winter temps requires shooting stopping every 2-3 shots to let it cool for 5-10 minutes. I've shot it at 300 yards a couple times but finally got to walk it out to 600 yards.

I used 4DOF to dial elevation and held for wind.

At 300 and 600 yards all shots would have been in a whiteail kill zone. (I forgot to stop at 3 shots as should, so I am not counting the 4th and 5th shots that went wide. If I needed 4 or 5 shots in the field, it's time to stop hunting.)

100 yds, 0.90 MOA
300 yds, 0.66 MOA, 2389 fps
600 yds, 0.91 MOA, 1841 fps

Afterward, I ran dropa and drift through JBM and its predictions were closer to my results than Hornady's were.

I'll practice more at distance and from fueld shooting positions instead of the bench. But now I feel confident this compact, super-light setup has the speed, energy, and accuracy needed for deer out to 500 yds if I can keep my technique up to par when not shooting from the bench.

 

[SippyCup]

Nice work! Just out of curiosity, what’s the minimum fps for proper expansion with the CX?

 

[BringBackThe80s]

Hornady says that bullet opens as slow as 1800 fps.

So, at 500 yds I'm getting 2025 fps and 820 ft-lbs: definitely enough for whitetails.

While it would be very unusual to get a shot opportunity beyond 200 yards around here, at 600 yards that mono bullet should still carry 675 ft-lbs and open up at 1840 fps. So the bullet should do the job at that distance, but I will need a lot more practice shooting long from field positions before I pull the trigger on game at 400 or beyond.

 

[SAUMan]

1:8 twist: 22" factory barrel on Remington 700 Alpha 1. 3013 ft/s avg, 103gr Hornady ELD-X, 47.0gr Ramshot Grand, full to slightly compressed load in new Peterson brass with Fed 210 Match primers. Depth .043" off lands. Most accurate load tested with this rifle.