Pardon me, but I'm totally at a lost with this ladder methods. Even the concept of doing it at 300 yards because it's supposed to be better than at 100 yards. It is my understanding that if your load would not group at a 100, it certainly would not group at 300 yards either. On top of that, variables will increase exponentially from 100 to 300 yards and beyond. Conditions change from time to time. Proponement of this methods probably eliminated a lot of good loads just because it did not group will when they did their ladder test. Are environmental and physical conditions were taken into considerations when conducting this test?
Like I said in my previous comment, finding load that works is not that complicated, especially when developing loads for a custom rifle, chambered for inherently accurate cartridge, like for the 308, with tons of data available everywhere.
I found this load for my 308 in as little as 10 rounds.
This is a starting load of 44.3 grains of varget shooting 155 Scenar. Found this load researching the net.
Next loading increased .5 grain to arrived at intended velocity resulted in this:
Here's the same load performed at 200 yards. 5 shot group:
No ladder test, nodes and all. I didn't even played with the seating depth.