Only seem to be hitting a single node

[lawman29]

Your posts indicate that your process is Helter Skelter, I've read this and that on this and that forum etc., gonna try this and that...
So let's start with the basics. What is your loading process, scale, size die, seater, press, brass prep etc?.
What is going to be your process to due load development step by step? Note: there are several different ways to get there, but one thing successful methods have in common is a structured process.
When you get to the range are you shooting off a bench, front rest, bipod, etc. Wind flag?

 

[searcher]

I'm curious as to what you tried in seating depths. If I were in your shoes, I'd take that powder that was shooting good and try backing that good load off a full 2 1/2 grains, seat the bullet to where it is touching the lands solidly, increasing the powder charge 1/2 grain increments until you show signs of pressure. Quite often, a bullet will like this arrangement better than off the lands, especially if you are using light neck tension. This puts the bullets in the "same" position before each shot and also eliminates some of the concentricity issues induced in the loading process. Because your rifle is shooting over "max" velocity doesn't mean it is unsafe for your particular rifle, though the swipes on your brass indicate you may be close. Many people will continue to run a load incrementally higher (cutting powder increases back to 2/10th grain) to see where real signs of pressure are evident. Not that you want to shoot at the level you find to be too much - just gives you an idea of how much of a margin you have between the load that you found accurate and what is clearly too much. Without knowing that - you could otherwise run into trouble on a hot day when pressure can build a bit more. Measure across the base of an unfired piece of your brass about 1/2" up from the rim. Then measure in the same place on the brass you have fired at the high velocity. if the fired brass grew by .001" or more, that is usually an early indicator that you are pushing higher pressure than you might like. I have several barrels that shoot a few hundred FPS faster (safely) than what are typically shown as "max" loads - and I have a few that won't even get to max without saying "enough".

Regarding the groups being "too small", if that was in reference to measured group size - you WANT smaller. If it is in reference to number of shots fired, 5 is plenty adequate. That said, when I get a couple of powders that are very close in accuracy, I'll usually shoot three (five shot) groups of each powder and average the three groups. Doing this in separate groups (rather than 15-shot groups) is important as conditions change while shooting and you are not looking at where the groups land on the target - but which average of the three groups was the smallest. Good luck!

 

[M14AMU]

Sounds like a good situation....in search of a problem!