I've been working up a load for the Sig 277 Fury (Commercial brass; Not the hybrid case) .
Here's what I've done so far.
I actually started loading with 39gr of BL-C(2), then 40.
Rifle Sig Cross in 277 Sig Fury
Dies Lee
Primer Winchester Large Primer
Powder BL-C(2) 41 gr
FPS 2467 av for 13 shots. Measured with Garmin
Bullets - Midsouth (seconds) Red-Tip 130gr
Average grouping at 100gr .6 MOA . My best grouping at 400yds was 2 MOA
COL 2.75"
All shots fired from a bench
Temp 41º, RH 32º
I'll be loading 41.2 next week, which xxlrloading.com is the max load with a 10% buffer. And I will update the information with the new data from the new load. I will reduce the buffer and continue to bump up the grains by .2 until I see signs of over pressure.
Hope that helps.