3rdgeargrndrr said:
Anyone try out the new Sierra Tipped MK?
I have a decent load with the untipped, wondering if load data should be nearly identical with the tipped?
Anyone with experience, or should I just stick to the untipped?
even a base to ogive measurement would help ;D
I shoot the TMK out of my Howa 1500 as well as the standard 69gr Match King and the 69 grain Moly coated bullet too.
I haven't put a micrometer to them, but I have gathered careful CBTO data on them and the TMK doesn't seem to be simply the standard with a plastic tip and the Moly version seems to be different too. In MY rifle, when seated to land engagement, they all measure differently. Here are the CBTO specs on MY rifle with the bullet touching the lands; yours will be different of course.
Sierra 69gr TMK BTHP 1.9925
Sierra 69gr Match King 1.996 0
Sierra 69gr MK Moly BTHP 1.9895
As far as accuracy goes, I don't see any significant difference between the tipped and non tipped bullets. They both shoot 5 shot groups averaging below .5 MOA including groups shot with rounds I loaded to something other than optimum charge weight during testing. With the correct load, they shoot right around .30 or .35 MOA in MY rifle. The Moly coated ones; however, show a bit better performance regularly producing 5 shot groups between .25 and .30 MOA and many times closer to 2.0 MOA.
Realize this is at 100 yards and results could be completely different at longer ranges.
At the moment I use 21.95gr IMR 8208 XBR for the Moly coated version. That is well tested and shoots well in MY rifle. I use 22.79 gr IMR 8208 XBR for the standard SMK and that seems to be the best in MY rifle. I use 22.85gr IMR 8208 XBR for the TMK version but I have less confidence that I'm using the best load for that bullet. In fact, I just made up a batch of 50 TMK rounds at 5 different charge levels to gather more data a little bit heavier and lighter than my current 22.85gr load. I don't exceed the recommended 23.8gr maximum.
Of course, YMMV so as always use caution and work up your loads carefully. Your Mother wasn't kidding when she screamed, "You'll shoot your eye out!!!".
