Re: Loads for .300WM-.300WSM
Went to the range yesterday, it was 110f when I was shooting, so some of my loads were hot. got some very interesting chrony results. I fired several loads on my 24" 300WSM with Reloader 19 and 17, with 208gr. A-MAX, 200gr. LRX, and 230gr. Berger OTM Hybrids. All loads with the same bullet were with the same specs, just different powder. Rirst up are the R-19 loads:
Win brass
CCI LRM primers
Barnes 200gr. LRX
2.910" oal (.065" from the lands)
66gr. = 2833fps average, 21 ES, .78 MOA
67gr. = 2867fps average, 16 ES, .81 MOA
68gr. = 2900fps average, blown primer, did not continue.
Remington Brass
CCI LRM Primers
208gr. Hornady A-max
2.950" OAL
66gr. = 2797fps average, 17 ES, .54 MOA
67gr. = 2815fps average, 15 ES, .51 MOA
68gr. = 2851fps average, 22 ES, .58 MOA
69gr. = 2884fps average, 20 ES, .61 MOA
These loads were all pretty accurate, but far lower than what I was expecting for this round. 69gr. gave me sticky bolts lift, so I wouldn't go any higher.
Win Brass
CCI LRM Primers
230gr. Berger OTM Hybrids
2.950" OAL
61.4gr. = 2580fps average, 45 ES, .85MOA
This was a very bad load, but I was surprised that there were no pressure signs, since I developed this load at 70f and it was already very hot; I might have to increase the charge and see where I get.
Overall, Reloader 19 was a disappointment. I was expecting higher velocities, but just could not get there without pressure signs as shown by me blowing a primer on the 200gr. LRX load. These loads were pretty accurate though, oddly consistent with most loads, maybe thats just my limitation though. Now for the reloader 17 loads:
200gr. LRX load
64.2gr. = 2980fps average, 8 ES, .52 MOA
64.7gr. = 3005fps average, 6 ES, .46 MOA
65.2gr. = 3027fps average, 12 ES, .67 MOA
All I can say is wow. Reloader 17 completely shattered the low expectations I had for this round and has made this the best hunting round I have so far. I wasn't expecting more than 2800fps since this is a very large bullet (1.624") and the load data Barnes has for the 200gr. TSX were all in the 2700fps range.
208gr. A-MAX
64gr. = 2879fps average, 4 ES, .74 MOA
65gr. = 2928fps average, 15 ES, .64 MOA
66gr. = 2968fps average, 8 ES, .53 MOA
I had a load with 67gr. but I got ever so slight pressure signs at 66gr. and decided not to continue.
Reloader 17 performed better than I could have possibly expected, especially with the Barnes round. I am kind of regretting not making some loads with R-17 and the Berger 230's, I might have to try some next time. This data just reaffirms in my mind that R-17 is THE powder for the 300WSM. What surprised me the most was the very low Extreme spreads I was getting with R-17, it was much more consistent than R-19. Also, the 200gr. LRX load with 65.2gr. was very hot when I tested it in 70F (65.5gr. gave me pressure signs), but in 110F there weren't any pressure signs, so that makes me believe that R-17 is very temp stable. I believe the very high speeds I was getting with the LRX in relation to the TSX is due to the fact that the LRX has a boat tail and the TSX does not, giving the LRX much less gliding surface and thus, much higher velocities. This load I believe is ideal for hunting anything in North America effectively, I found a round in the backstop that was perfectly expanded to .7" in size.