OCL to 3.681 to fit my sako trg mag.
My pet load is 300gr SMK, 90.5gr H1000, avg velocity 2759 with ES of 19 fps 500 yd 5 shot groups are 1.109" shot from a Sako TRG42, Nighforce 8-32x56 NXS, NP-R1.
I started loading for my 338 with the hopes of using the 300 gr Berger hybrids with an OCL to fit my magazine but after trying both reumbo and H1000 starting at 89.0 grains of each and working up by 1/2 gr I was only able to come up with three loads that were 1/2 to 3/4 moa at 100. I took these three loads and worked up and down .1gr at a time without any better results. I worked up both powders until signs of pressure started which started in the retumbo at 92.0 gr and in h1000 at 91.5gr. Of the three loads that were 1/2 to 3/4 moa at 100 only one held 1 moa at 500 which was 89.5 gr of Retumbo.
I decided to try the 300 SMK with Retumbo and H1000, starting at the same spot and same OCL. Results were impressive. I ended up with 3 loads that shot under .350 at 100. 90.5 h1000, 90.5 Retumbo and 90.0 Retumbo. 500 yd 3 shot groups were .997" 90.5 h1000, 1.601" 90.5 Retumbo and 1.490" 90.0 Retumbo. I decided to stay with 90.5 gr H1000 even though all 3 loads shot very well because my ES with retumbo was around 80-95 fps and only 19 fps with H1000.
After this long winded post, I am simply trying to let you know it may take some time to come up with a load. I shot 21 different loads before I found the one my rifle liked so be patient. Accuracy nodes like Broz was talking about are what you need to look for.
I am in the process of studying a load for a trg 42 as well, and I am not finding otm 300 gr bulets to be very accurate (as far as now 91.5 gr of h1000 gave me about 4 inches at 500 yds). I am jumping 0.07 inches, maybe that's too much...
I read with interest your post, did you find any other interesting loads e.g. with other bullets? how do sierras matchking 300 gr perform on deer? (that's the game I will shoot hunting)
300 Berger HTM's seated .025" off the Lands, Lapua brass, Fed215 Primers. Redding .365" Neck bushing, 90 gr H1000, 2725FPS, .25-.5 MOA
Hi Greyfox. I'm working a very similar load. Can you please confirm that you are using Berger 300gr Match Hybrid OTM Tactical bullets? I'm surprised to see many posted ~90 gr H1000 loads with this bullet while Berger shows a max load of 85.2 gr. Is it because Berger tested with a relatively short COAL of 3.681" for their test data? I'll be at 3.891" if touching the lands in my rifle (will seat a few hundredths deeper than this), so I expect less pressure.