020 starting point that Panhandle Precision uses for his custom reamed match rifle. Should I have arrived at this differently? Granted,with what looks like 0.174" of jump, I'm not expecting to get anywhere near the Berger ideal jump of. 002 even with a micrometer seating stem would be chasing my tail). 030" adjustment to get the same jump, I seated the 169 SMK's to 2.187 BTO (close enough to my goal of 2.185, the last. Math's not my strong suit, so check me on this, but my GMM clone loads with 168 SMK are seated to COL 2.805 (book length being 2.800) which measures on my BTO comparator at 2.215. 030" to get a similar jump.PLEASE DISREGARD THESE NUMBERS SEE NEW REPLY JAN 22, 2023. So that gives me a comparative adjustment of. What was your base to ogive for 175's at COL 2.800, or 168's at similar overall length? Based on the Hornady OAL gauge and BTO comparator, I believe the difference in bullet profile (and the way it meets the angle of my rifling at the leade) accounts for the 168 SMK touching the lands in my M1A Loaded (.308 Win chamber) at BTO 2.391, but the 169's would touch if seated at BTO 2.361. Here are the Mk11's drop charts for the 169 and 175 side by side: Data was taken at the same shooting location. 2 mils and shot another 5 rounds, which can be seen in/around the water line (yes, my water lines are a bit thick and not entirely straight - going to make/use a card board template to paint them for next time). 3 mils left wind hold at 650-700m.Īt 700m, I initially went with 6.2 mils, which resulted in the two low impacts on the target, one at 5:30 near the bottom edge and another at 8:00 left edge. Conditions were largely the same as last week, the 169 required between. Shot the same above 43.1g load at multiple targets in 100m increments out to 500m then from there, 50m increments to 700m. I elected to load up 40 more rounds at 43.1g Varget for additional testing (see below). 2-.3 mils less wind compensation vs the 175. Excluding that shot, the SD would have been 15, ES 54 which is more typical.Īt 600m, the 169 was. * The cold bore shot with the 175SMK was 2637 fps, which was 36 fps higher than the next fastest round, skewing the SD/ES numbers for that load. Testing at 100 meters yielded similar or slightly better group sizes compared to the 175 so the rifle likes the bullet. Every round was measured to confirm seating depth was within those limits. I set the CBO for all test samples at 2.110” +. Though they are brand new, I figured them to be insensitive to jump like the legacy SMKs. Loaded 15 test rounds each consisting of the 169SMK at 42.8g, 43.1g and 43.4g Varget. Here is the loaded round in selected short action magazines.From left to right: KAC Steel, Magpul AICS, Accuracy International AICS, Accuracy International AX d/s, Magpul P-MAG for SR25/AR10s The extra length shouldn’t be an issue for most bolt guns but will be cutting it really close for semi-autos depending on what mag you run. All rounds were loaded to a cartridge base-to-ogive of 2.110, which put the OAL at 2.850, quite a bit longer than the 175 SMK which I load to a COAL of 2.800. Primer was a Remington 9-1/2 Standard LRP and cases were 1x fired and full-length sized Lake City LR 07. I used Varget and chose three charge weights, 42.8, 43.1 and 43.4. 169smk is on the left and 175 smk is on the right in both images. Here it is compared to the 175 along with relevant info. Specifically, they intend for this bullet to enable the 308 Winchester to be consistently effective out to 1,000 yards (915 meters). Sierra clearly designed this projectile to compete with some of the more modern, higher BC bullets in the 165-185 weight class like the Hornady 178 AMAX/ELDM and 185 Berger Juggernaut. The bullet itself has a much longer, more streamlined profile compared to its elder siblings, the 175 and 168. 527, which is an improvement of 31 basis points from the 175 SMK’s G1 BC of. Then today (Feb 15th) I shot an evolved version of one of the test loads at steel from 300m to 700m. On Feb 7th, shot three different loads side by side with my standard 175SMK load (load details below) at 100m and 600m to compare elevation and wind holdover requirements for each bullet at 600m from a 100m zero. In short, they seem to be markedly better ballistically than the legacy 175 Matchking. I developed a few quick loads using Sierra’s new 169 Matchking and tested them yesterday in the desert. Overall, I like the 308 but found the 175SMK to be lacking consistency beyond 700m (that’s after I factor me as an average shooter out of the equation). Had a chance to load up and test the new 169SMK in my Mk 11 Mod 0.
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