Here is a series of real world tests on a variety of powders in the 5.56 (Wylde) attempting to duplicate the factory loading of MK 262 as produced by Black Hill, 77 gr SMK.
When you open the link, the entire series, by test episode, will come up on the right.
In almost every case, his results have pretty closely mirrored my results with the same combinations, so that's why I say it real world.
MM
Duplicating MK 262 from Black HillsMM, thanks for the link, but there's more video there than I could watch in 2 weekends,
What are you trying to say, whats your go to load?
Okay. I shoot bullets from 55-77 gr. exclusively in my guns.
After testing & working with a lot of different powders, I have settled on 2 primary powders that do very well across that bullet range, giving very good accuracy with all & as much velocity as can safely be wrung out of a 5.56 (223 Wylde) with an 18 or 16" barrel.
Those 2 are IMR-8208XBR & Alliant AR-Comp. They are both very small grained extruded powders that feed & meter very, very consistently.
With AR-Comp & the 77 gr. SMK, Nosler CC or Nosler RDF I am loading 23.0 gr.
With 8208 & those same bullets, I am loading 23.5 gr.
In all cases, I am loading to 5.56 pressure level, as best as I can determine & comparable to factory MK 262 & IMI Razorcore, both are loaded with 77 gr SMK.
Both powders provide a smooth recoil impulse as compared to say, H4895, which to me is significantly sharper & quicker, which I do not like.............but I will use H4895 in a bolt gun, not in an AR if I have a choice.
If I were only going to load 77g. bullets, Alliant 2000-MR would probably be my single choice; it feeds even better than AR-Comp or 8208, it's very accurate & will give just a little more velocity, especially in an 18 or 20" barrel than the others. But it also takes more if it to get there.
If I were only loading bullets of 60 gr or lighter, then I would choose VV-133............it's the darling of BR shooters with light bullets, & for a very good reason. Meters well, provides very low SD's & is more accurate than virtually anything else with light bullets. I also use it in bolt guns.
As to the old standbys of RL-15 & Varget, I can't think of a good reason to use them as the others are about as accurate, meter much better & give higher velocities..............Varget probably get's the nod as being
THE absolute most accurate of the bunch with heavy bullets, if you want to accept 75-100 FPS lower velocities, & poor powder feeding with corresponding more variability round to round, & except under bench shooting conditions, the accuracy difference isn't enough to talk about, IMO.
As for CFE-223, which has come up here several times, it feeds well but I have not found it to consistently equal the accuracy of any of the powders mentioned above, nor is it really any better velocity wise, plus it takes over 25 gr to get to top velocity. I have not tested it for tempt stability.
Everyone has their own reasons for what they pick & these are just mine.
Given today's supply situation any of a dozen good powders will all work acceptably, some just do some things a little better than others.
YMMV
MM
