Greetings, my first post, been lurking for a while and now here I go. Pardon any newbyitis. I am a lifelong hunter, but only for texas whitetails mainly, until 2 years ago when I went on my first elk hunt. To honor the horseback Frank Church trip and the game, I bought a Tikka T3 Lite in 300 WSM and began load development. I narrowed down to the Nosler Protected Point in 180 grains. Since then I have read a lot about the Optimal Barrel Time stuff, have the calculators for OBT, and have been using Quickload to help plan loads in some ordinary and some weird rounds (30-25 WSSM). OBT works a charm in getting you to accuracy nodes, in my experience. Once in the region I do OCW to narrow it down to tack driver. Now I have another Trip of a Lifetime planned, for elk again. So I was revisiting my old stuff, and noticed the OBT for the Tikka's 24.375 inch barrel were way below the max load shooting 180 grain pills. ALL of them. The gun was only accurate to my standards with about factory load velocities of 2950 fps. On a whim I plugged in 165 grain TTSXs and Partitions and Accubonds to Quickload, using RL 17. Much to my surprise I found that the programs predicted i could step up the 165s to the node (in OBT terms) that the 180s could not hit and still be 2000 - 3000 psi below max. In plain terms, it looks like I can take the muzzle energy of a 165 to around 3850 ft-lbs / 3250 fps, and be safe, where the 180s would only reach 3500 ft-lbs/ 2950 fps or so while still in an accuracy node. 300 ft-lbs seems like a lot of advantage. With the accubond for example, that increased the magic 2400 fps hydrostatic shock theshold from high 300 yard territory for the 180 grainer to over 450 yards with the 165. I am a big fan of hydrostatic shock to bring game down fast. Though I will try and remaster the 400 plus range before the hunt, I don't plan on shooting much further than that. So my question is, are the 165 grain TTSX, Partitions and Accubonds (et cetera) excellent for a rapid kill of bull elk at those ranges/ velocities? Or should I stick with my 180s? Great site here, and I appreciate all you all have taught me.