RS powders for heavy .223/6.5CM/.308 bullets

[MichalS]

After doing some additional reading (Laurie's threads  were very informative as always) I decided to skip the Lovex and go for Reload Swiss powders. I will be reloading:

- 24" 1:8 twist Tikka .223 with 80gr SMK

-28" 1:11 Sabatti .308 with 185-200gr Berger

- 28" 1:8 Sabatti 6.5 Creedmoor with 142-150gr SMK

Which specific RS powders would You recommend for each of those?

Is there one that can do it all reasonably like Hodgon Varget?

TIA,

Michal

[VarmLR]

I'm not sure that one would do it all but RS50 would tick the .223 box and might also do the .308 (I've used it with 77gr smks in .223 and 190gr smk in .308 and very good it was too).

The 6.5 will work well using RS60 or RS62.

[Re-Pete]

As previously stated, 223 SMK80 with RS52.............and possibly 6.5 Creed with RS52 and RS60. (I've tried both with 6.5x47.....jury is still out. Both produce 2900fps with 136 grain Sc's)

Re-Pete

[Laurie]

RS52 would just about do the lot, although I'd seriously recommend slower burning RS62 for the 6.5 where '4350 class' powders are optimal. 52 suits the 223 and 308 applications very well though. Nitrocellulose only RS50 probably will too but will give lower MVs, in mitigation produce a bit less barrel wear.

[MichalS]

Thank You all. Am I correct that single base RS50 will also be less temperature sensitive?

[Laurie]

Maybe, but I've never had any issues with RS52 in this regard. When I was loading 308 Palma brass with a trial lot of Nitrochemie EI-N130 (nicknamed Elcho-15) some years back that I was given by Nigel Cole-Hawkins for review in its pre Reload Swiss days, I intended to use it in quite a 'warm' load at the Scottish LR Championship meeting at Blair Athol a couple of weeks later in what promised to be very warm conditions. So to test its temperature sensitivity, I left an MTM 50-round box open on the front seat of the car for three hours straddling midday in full sun on a hot day at Diggle to see if I could detect any difference. I couldn't and the chronograph only gave a modest increase in MV. (EI-N130 is the works code for what is now retailed as RS52.)

No powder, even the much vaunted ADI / Hodgdon 'Extremes' is completely temperature insensitive, it's more about being manageable in one's own conditions, and managing ammunition exposure on the firing point. I cringe when I see F-Open competitors shooting a 40 minute or so relay on Stickledown with those big MTM R100 type ammo boxes sitting in full sun and the lid thrown back. By the end of that relay, those rounds will be noticeably hot to the touch. The same competitors will (rightly) take great care to keep their ammo out of the rain on a wet day knowing what water droplets can do to pressures and precision, but ignore full sunlight which even in the UK can be hot.

The only powder I've had real issues with is Re15 in my old 223 90gn F/TR load that was pushing pressures. I could watch primer cratering get progressively worse as ammo heated over the course of a hot day. An insulated sandwich bag was bought and by scrupulously keeping it and the ammo in shade, opening the box as little as possible and not keeping rounds in a hot chamber got around this, but only barely. RS52 seems to be the answer to this issue in the cartridge and combination as VarGet solved the temperature problems but lost 60 vital fps and never performed as well as the Alliant grade.

[MichalS]

Thank You guys - I will start with RS52