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. [Edit: Now I can't find where I saw that number from Hornady or a retailer, so that is likely 200fps too slow.]

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.

 

[Benchrest Braxton]

I love the ruger american rifles, I think its the nicest factory rifle on the market for the price point.

 

[mtnbound]

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.

Hornady recommends 2000fps or more for the CX to work optimally. I think sub 400y your fine but over that distance I wouldn’t count on good terminal results.

 

[SippyCup]

Hornady recommends 2000fps or more for the CX to work optimally. I think sub 400y your fine but over that distance I wouldn’t count on good terminal results.

I have loaded Barnes and they recommend the same. They say 1800 minimum but suggest keeping it above 2000.

 

[BringBackThe80s]

Hornady recommends 2000fps or more for the CX to work optimally. I think sub 400y your fine but over that distance I wouldn’t count on good terminal results.

I just looked for where I saw the 1800 fps figure from Hornady a few weeks ago, but now I can't find that. Weird. I edited my post above and added a note saying that number may be erroneous.

I mainly bowhunt and never expect that a deer will drop on the spot. My .243 load is still moving 2025fps at 500 yards, so and I'd probably be comfortable with a bow-hunting style shot at that distance. But unless and until I finally go hunt out west, the chances of me ever shooting that far are extremely remote.

 

[wind gypsy]

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.)

What if your 4th and 5th shots were your 1st and 2nd shots?

 

[BringBackThe80s]

What if your 4th and 5th shots were your 1st and 2nd shots?

They weren't. The electronic target shows each shot upon impact. It can also display the shot order for the entire group.

 

[wind gypsy]

They weren't. The electronic target shows each shot upon impact. It can also display the shot order for the entire group.

I'm not arguing the facts of what happened but rather the interpretation of the facts. You missed the target on 2 out of 5 shots from as stable a position you could get at a square range. I'm saying those could just as well have been your first two shots rather than your last two. To extrapolate that only the shots that hit your target are the ones indicative of you and your rifle/ammo's expected performance is not logically sound.

 

[BringBackThe80s]

I'm not arguing the facts of what happened but rather the interpretation of the facts. You missed the target on 2 out of 5 shots from as stable a position you could get at a square range. I'm saying those could just as well have been your first two shots rather than your last two. To extrapolate that only the shots that hit your target are the ones indicative of you and your rifle/ammo's expected performance is not logically sound.

Except that after ~300 rounds through this gun, the established pattern is the very thin barrel keeps the first few shots tight, but if you keep shooting without of letting it cool for 10 minutes, the 4th and subsequent shots open up the group. If you stop to let it cool every 2-3 shots, it rarely throws any flyers.

But, hey, maybe it was me and I botched both those shots to an unusual degree.

A lot more practice at 300 and 600 (with a cool barrel) will tell the story.

 

[elsb0048]

Except that after ~300 rounds through this gun, the established pattern is the very thin barrel keeps the first few shots tight, but if you keep shooting without of letting it cool for 10 minutes, the 4th and subsequent shots open up the group. If you stop to let it cool every 2-3 shots, it rarely throws any flyers.

But, hey, maybe it was me and I botched both those shots to an unusual degree.

A lot more practice at 300 and 600 (with a cool barrel) will tell the story.

Have you ever compiled larger groups of your first 3 shots either on the same target with cooling in-between or plotting/averaging with excel?

 

[BringBackThe80s]

Have you ever compiled larger groups of your first 3 shots either on the same target with cooling in-between or plotting/averaging with excel?

Almost always. That's what the 100 yd paper target above is, a 10-shot group that I shot in 4 strings of 2 and 3 shots each during my last range session before deer season.

A couple weeks ago I just had 8 rounds handful left over from hunting season and wanted to see how they would do and how the scope would track at distance.