[musketjon]

I’m using a standard set of RCBS small base dies.
Jon

[musketjon]

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

[musketjon]

Load up a few and see how they perform. It will be dependent on the groove diameter of the barrel. Worst-case scenario is they’re undersize and they’ll rattle around in the bore like a horse turd in a post hole and accuracy will suffer.

Jon

[musketjon]

Try adjusting the seating depth. Try some a little shorter (deeper seated) and some a little longer. The published coals are just a starting point. Your rifle may prefer a shorter or longer coal.

Jon

[musketjon]

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

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