Re: 338 Norma Magnum
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HiCapMag</div><div class="ubbcode-body">FK300, I would like to hear your results with Retumbo. I asked about that and it was suggested that it was a tad slow...but let us know.
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Stealing a quote from a previous post of yours: Warning, if you use these loads in your rifle without working up, it may kill you and everyone you know and destroy life on the planet as we know it!
I shot 50 rounds from 200 - 1000 yards Saturday in 60 degree, gusting switching winds (7-15mph from 9 o'clock, then calm, then 7-10mph from 3 o'clock...all within a few minute time period) groups were excellent out to 600 yards with 92.0 gr of RSM, 3.590 with 300 SMK & F215M primer. 800 - 1000 yards I had very little vertical dispersion but the horizontals, (100% miscalculating the gusty wind conditions so the wind kicked my ass) left a little to be desired at the longer distances. Half the box of 50 cartridges was brass that had been formed fired and full length sized (.001 reduction in the shoulder) and the other half was new. The brass, that was formed fired, after firing was a little sticky in the chamber. No problems opening the Stiller TAC338 bolt but the case required a little tug (couple of pounds) to dislodge. Using the exbal program for conditions and calculating 2805 for velocity, MOA elevation calculation was spot clear out to 1K. I think I'll try to lower the load to 91.5 to see if I can eliminate future chamber "sticky" problems.
I hadn't had time to reload Retumbo...but will hopefully this week. I did get a chance to load a dozen rounds using RSM on new cases to check pressure using a 250 gr Sierra Game King (hopefully a successful Moose load next month).
The grouping was excellent @ 100 yards. Semi-Bug hole (every round touching) for all test loads. I used 95, 96, 97 & 98 grains of RSM. No pressure problems with 95 & 96 gr but 97 and 98 were just a little sticky in the chamber (although the primers did not indicate pressure problems). I forgot the chronograph...so I can't tell you the speed. I'll update soon on more powder trials and 250 Gr SGK speeds and performance at longer distances.