I have a Winchester model 70 extreme weather in 325WSM, had it a couple years and worked up several loads for it. Developed a 200 grain Accubond load using Reloader 17 that is sub-moa and over 3000fps. Once dialed in, I loaded up a 100 or so and went out last year and killed everything I pointed it at.
On my goat hunt I took a bad roll down the hill with it. After about a 500 foot uncontrolled tumble I was scuffed up and my Winny was stuck in the ground up to the stock.
Cleaned it up when I got home and took it back to Kodiak Brown Bear hunting. Wanted to use a different load for bear hunt so I test fired the rifle and re-zeroed it with a 220 grain Aframe load. All was well and the rifle shot and grouped them well.
Fast forward to this year,, having shot up all my Accubond loads I loaded up some to take for sheep hunting and headed off to the range to zero for my Accubond load.
Using a solid rest and bench, try as I may I could not get them to group. All over the paper and totally inconsistent, thinking it may be the rifle or scope, I shot a group with other proven loads and they all shot and grouped well.
Well, I chased my tail for 4 days, and just could not get the Accubonds to work. Thought I had got some defective bullets since a new box of bullets was the only thing different, same lot of powder, primers and brass.
Totally flustered, I decided to remeasure everything and discovered that I had mistakenly recorded the COAL and was seating the bullets too deep. Instead of .005 off the lands I was seating them .050 off the lands.
Loaded up a new batch and hit the range yesterday and was putting them into a dime sized hole once again.
Lesson learned,, don't think it would have taken me that long to figure out if I had not had reason to question the rifle and scope after the fall.
The good news is during the process I refined 2 of my Barnes 200g TSX loads into submoa loads.
Just though this info may inspire other loaders to check and double check everything.
Be safe and shoot straight.