I, too, have a couple of boxes in .30 Cal to try.Novice so please be patient. I'm still ignorant in a lot of ways which is why I'm hoping you guys can help me find good loads and stay safe.
Does anyone have any load data or suggestions for 270 win for either the Norma 140 gn Tipstrike or Sierra 140 gn Tipped GK with either Staball 6.5 or Ramshot Hunter?
Concerning these powders, are there equivalents or close equivalent powders out there? I have the burn rate chart but that just puts them in order.
One of the unique challenges I've found is that the Tipstrike seems to be shorter from Ogive to tip than most bullets. It doesn't look unusual but when I used the "redneck" method for measuring max seating depth I got between 3.25-3.26 OAL. I have a decent shooting load with the TGK at 3.360 (magazine max). I believe it is still .020-.030" off the lands. One hundred thousandths different for two tipped, 140 gn bullets seems odd.
With the Tipstrike it seems like pure experimentation. The bullet seems to be different enough from other bullets that published loads aren't that helpful.
Currently with Tipstrike I'm at 3.230" OAL with 54.5 gns of Hunter and no signs of pressure. That is .060" greater than Norma's data says. (The factory loads are about that too). The factory rounds are so hot that I got an ejector mark on a case but just better than the 3084 fps velocity. The current load is giving me an average of 2912. The SD was under 10. Only Nosler publishes a max load higher than 54.5 gns of Hunter for a 140 gn bullet- quite a bit higher at 56.5 gns.
I have loaded rounds to try 3 more steps at 54.7, 54.9, and 55.1. Am I safe with these? How high should I challenge it?
With the Sierra TGK and Staball 6.5, I grouped about .6 MOA which is good for me. The load was 55.0 gns seated at 3.360 yielding 2970-3000 fps. Anyone have something better I can try?
PS- Even if you have no input on the other I am curious if anyone else sees what I've seen with seating depth and velocity. On BOTH it seems that seating deeper has resulted in lower velocity. I would have expected the opposite. Is that just a matter of how efficiently the powder is being burned with more room in the case?
PSS- Why Tipstrike? The factory load outperformed every other bullet I tried both for V and accuracy. I also found a great deal on them at Raven Rocks. On sale- $19.95/100. All of the reviews looked good if not great for the bullet performance.
This is from Norma's reloading center.
These powders are scarce or non-existent these days. So, look for powder with the same or close burn rates.
Good luck!