I started out with Varget in my 1st Dasher in 2004, then moved to Viht N150. Got a little more velocity & cleaner burning with N150, but accuracy at 600 was really excellent with both. I found myself using about a half-grain more of N150 than Varget; was running 3060-3070fps out of 30" Krieger .236"/1:8. Latest jug of N150 is faster - I've had to back off a half grain to avoid ejector swipes in my BAT 3L, even though the latest bbl. is a .237" vs. the old .236".
I sent my Dasher reamer back to PTG to have the freeebore shortened from .158" to .123", and chambered a 30" std Palma Bartlein 5R .237"/1:8 for the BAT 3L prone rifle. Not sure what's going on, but so far, I've not found a load with 105 Hybrids, VLDs, nor Lapua 105s that will shoot under 1/2 MOA at 600 with either Varget or N150. Haven't had a lot of time to focus on this rifle, as I'm working with several others at the same time I'm doing fall planting & trying to get ready for corn harvest, so don't take this post as a knock on Bartlein, Berger, or PTG.
I'm about ready to put an older Krieger back on this action, but will try more different seating depths & maybe even give RL15 a shot first. Just slightly frustrated, as I've had such good results over the past eight years with N150 in various Dashers, including another BAT 3L LR BR rifle that's currently shooting quite well with the same lot of N150 that I'm using (or trying to) in the prone BAT.