.224 75gr 3GH precision results?

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 was recently comparing the accuracy/precision of the RMR 75 grain hpbt to SMK 77’s for a 600 yard load. All shooting was from a bench at 100 yards in a zero wind range, rifle fully rested front and rear. 10-shot groups. Rifle is an off the shelf 20″, A2 govt profile, chrome-lined barrel, 1:7 twist (not exactly a “match” barrel).
Anyway, the load was 23.5 grs of H4895, c.o.a.l. was l-o-n-g at 2.380″ (for slow-fire, single-loaded string in xtc matches). Don’t have a chrono so velocity is any body’s guess.
BOTH, the RMR 75’s and SMK 77’s had the exact same extreme spread of 1.38″ (1.32 moa). The mean radius of the RMR was .61″ (.59 moa). The mr of the SMK was .5″ (.48 moa), but only because 2 rounds were touching. As stated, the es was exactly the same with both bullets, soooooo, I’m a firm believer in the RMR 75’s.
I’d post pics of the targets if I knew how to do it.
Hope this helps you out some.
Jon

81degF, mixed LC, CCI450, Staball Match pressure/velocity eval, COAL 2.25″, Lee FCD 1/4 turn

16″ ARP barrel w CLE chamber, Labradar

25.0 2595
25.2 2618
25.4 2631
25.6C 2665
25.8C 2697

All brass looked good.

I use a Hornady die with a modified VLD stem, I did a little polishing to get a little better fit in the stem. Most of the time runout is less than .0015 with an occassional .002. I just set the bullets on top of the case and guide it into the die and seat in 3 steps and turn the case at each step. Seems to work for me.