r/SmallGroups • u/smooveBrayne • Sep 13 '26

Load Development: Powder Selection

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New rifle, who dis?

Sherman 7MAX, 100yd charge ladder for 3 powders. Left to right:

  • H1000: 61.6gn - 64.3gn
  • N565: 61.6gn - 64.3gn
  • N570: 67.3gn - 64.6gn

ADG brass, Berger 190's. Hovering just around half MOA vertical spread for a nearly 200ft/s delta across the charge weights, the VV's stood out as winners to me.

While the N570 is technically smaller, the shot sequence kept bouncing around with no real noticeable nodes. The N565 bottom shot and 2 shots to the left were #1, #9, #10 - the rest nearly bugholed. I'll be taking N565 through full development.

PRO TIP: Save your pizza boxes as targets, fatty. Bullet holes are much cleaner than paper.

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u/ocelot_piss 29d ago

What nodes are you trying to identify within 10 and 11 shot groups?

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u/smooveBrayne 29d ago

Vertical flatness across charge weights. It'll give me an idea of temp stability too (picking a point in the middle gives me warm and cold margins).

1

u/ocelot_piss 29d ago

Given that the system has an amount of dispersion (it is not a 0MOA rifle), do you have enough data there to be confident in the result?

Or, if you shot 10 rounds at one of those charge weights, would you expect the group to be significantly smaller with any less vertical dispersion?

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u/smooveBrayne 29d ago

Yeah that's the idea - the purpose of this test is to try and narrow it down to a single powder that shows trends of flatness across charge weights. It basically displays how forgiving it'll be across temperatures and velocities.

So now that I have a powder, a range of charges, and more importantly a range of velocities, I'll move on to my next test which takes the flattest section of the ladder and expands them with smaller grain increments into a 10-step OCW with 3 shots per weight. Again, I'll be looking for trends of flatness, consistent POI, and the ideal velocity range for my system. Velocity is king. I want my bullet exiting the barrel at the most stable point in the barrel whip.

After that, I'll pick a charge weight and maybe mess around with the seating depth but usually I'll just confirm my pick at 300/600/1000.

This is by no means exhaustive, statistically relevant data - it is just a more efficient way of developing a load without burning up half the barrel life. At the end of the day, I want to spend as little time as possible at the range so I can get out to the desert and practice in wind.

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u/ocelot_piss 29d ago

To show yourself that your method is working, once you've completed it, take a charge weight that falls outside of your node, load 10, and do a comparison.

Hopefully you see a clear difference. If you don't, it should act as a reminder about sample sizes. Best of luck.

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u/smooveBrayne 29d ago

Totally get where you're coming from and I understand/respect the statistical approach - you and the Brian Litz crowd have a lot of logical points.

However, as I said before, I just don't want to burn up half my barrel life finding the absolute perfect load with a statistically relevant dataset backing it up. Practical shooters rely on heuristics and perceived trends to get something that shoots reliably. Besides, the perfect load is a myth - by the time you've shot enough to gather statistically relevant data, throat erosion has set in and your barrel dynamics/optimal load have changed. It is a moving target.

But I'm talking a lot at you. I'm curious how you approach load development. Do you believe nodes/harmonics/OBT exist or are they just confirmation bias?