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CFE223 Ladder from 25gr – 26.5gr. Max charge was my pick. Moved in .3gr at a time
CCI 450 Primer
LC 5.56 Nato Brass Annealed after every firing
OAL: 2.245\”-2.255\”, the meplate is a little inconsistent, as expected from open tip
CBTO: 1.895\”, this was consistent across my loading
Ring Crimped with Lee FCD
Using Criterion 18\” Core Bbl.
Average MV: 2919fpsMy worse groups were at the lower end of my ladder testing. Worse group was around 3\” in the 25gr-25.6gr range. Things started to tighten up as I approached 26gr. Shot my best 10 shot group with a max Hornady load with their 75gr BTHP under 26.5gr. Got a little under .875\” with my best grouping. Other 10 shot groups under 26.5gr was slightly under and slighly over 1\” with my max being around 1.375\”. 10 shot groups are hard, even when using a sled so I could have been my technique. I still have more testing to do for consistency.
In my experience CFE223 performs best at max charges and honestly I\’ve only seen it get better past max if you\’re confident enough. I went all the way up to 27grs just to see what pressures would look like and see if I had a generous margin of error. Groups were around the same size as 26.5gr but I started getting raised ejector smears on the brass. No blown primers though.
I understand CFE223 is temp sensitive but I live in Hawaii so its pretty much always summer here and not too concerned.
Just wanted to update everone with my testing. I was able to take this bullet out to 875 yards today at human torso silouettes.
At an average of 2900fps muzzle velocity out of my 18″ Criterion Barrel, the BC that holds the most true to my dope I used at 550, 675 and 875 yards today is G1 .37
From the range a few weeks ago, I got 2756 FPS with 24.3 gr Ramshot TAC, Win #41 annealed (white box) primers, 2.255\” OAL, and of course the 75gr 3GH. This is from a 16\” 1:8 twist Ruger MPR. Note the range has a large, thick baffle about 10 feet from the shooting bench, and we shoot under the baffle. The chrono really didn\’t like that and we only got the one good data point. Still, 2750 is faster than I was expecting. No real pressure signs on the PPU brass. Eventually I\’ll do some accuracy shooting at 100 yards with a 3x optic.
First post here, thanks for the info and I will also pick up more of these RMR 75gr BTHP.
I plugged them into a 75gr rookie load I started with Hornady BTHP Match using H335. I have not tried these on paper, but took them out to 700yds in 100yd increments (beginning at 200)
16\”bbl, 1:7
21.9 gr of H335 (so far), 2490fps mv.I\’m looking forward to seeing groups on paper, and trying other powders and charge weights.
I just ran some ladders with Staball Match powder. It looks really promising. All groups were about 1/2 inch.
I shot the 75 grain 3GH bullets and Sierra 77 grain SMK.
Bullets were fired from a 20 inch custom build 223 wylde 1:8 barrel. The 3GH bullets grouped slightly better than the SMK and speed was also a little better. SDs were 4.4 3GH and 4.7 for SMK. Best group was a .227 from the 3GH and. 375 from the SMK. Best speed was 3GH 2714, SMK 2658. Neither load was maxed out. I think I can get a higher node on both before seeing pressure signs. I shot these using IR night vision scope during daylight. I have coyotes in my food plot and I have to fix that problem before I do more testing.Just wanted to provide an update. Been playing around with seating depth to try and squeeze a bit more accuracy out of these bullets. Moving from an CBTO: of 1.895\” to a 1.885\” using a Hornady Bullet Comparator Ive been able to shink my group sizes down from an average of ⅞\” to an average of just over ⅝\” in the .68\” – .72\” range.
I also dropped my power charge from 26.5gr CFE223 to 26.2 and still yield the same MV from my 18\” Criterion Core Barrel. Still using a Caldwell Lead Sled and 10 shot groupings.
Im sure Im limited by my Nightforce 1-8 LPVO at this point. Will try using a higher magnification scope that has parallax adjustment when I finally get one.
90JS
Those sound like good groups. How many rounds did you shoot per group? Also, did you see any vertical stringing when the barrel gets hot?
I was doing some long line (600 yd) workups a couple of days ago. 23.5 grs of H4895, bullets seated at 2.380\” coal (single-load for the long line strings in xtc) and I got a 5-shot group that measured 1.38\” extreme spread at 100 yds. Keep in mind, the rifle (and barrel) is an off the shelf Windham 20\”, govt A2 profile barrel with a chrome-lined bore and chamber. I also got a 5-shot group from the same test with SMK 77\’s that also measured 1.38\” extreme spread. Same powder charge and coal. The results speak for themselves. I\’d post pics if I knew how, here.
For mag length I load them at 2.210\” coal and get similar results, same load. I\’m sure with a better barrel the groups could be improved upon.
Apparently MY barrel prefers extra long and extra short coals.
Hope this helps you some.Jon
I took a friend of mine\’s great grandson deer hunting tonight. My friend passed away not too long back, I was keeping a promise I made to him. The boy is 10 years old and got his first deer tonight with a 75 grain 3GH bullet. The deer was about 60 yards away on a small hillside, the bullet caught the edge of the shoulder and exited mid ribs on the other side. The exit wound was more than 2 inches in diameter. The top of the heart was blown up and the lungs destroyed. The deer went about 30 yards into the woods with a blood trail that anybody could have followed. Pretty good for a 556. It made a memory that neither one of us will ever forget.
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