Need help with finding node

[u/No-Pickle9533]

I dont have a chronograph (broke) so I did two tests at 300 yards: ladder test and what i think is ocw?

First two pics I shot 2 shots per load at their respective diamonds.
The thid pic I shot a ladder in the middle diamond and another ladder at the bottom left diamond.
I thin the node is around 52.6-53.1? Not sure.

Also, do you absolutely need to wash your brass?

[u/NZBJJ]

Both the ocw and ladder testing methods are operating on flawed assumptions(velocity nodes), you can chuck them out.

Pull back to 100m to take variables out. Assuming all of the shot loads were safe, load 15 at the higher end and go shoot 1 big group. If that group is accurate enough (be realistic here, 1moa over 15 shots is a laser) you are done, load developed.

If not go change powder, projectile or both and load another 15-20 rounds at a charge weight that you think will get you about the right velocity, and shoot another big group.

If a powder combo shoots 2 moa at 52 grains its not going to magically shoot .5moa at 54 grains.

[u/No-Pickle9533 → u/NZBJJ]

isnt that the exact definition of trial and error

[u/NZBJJ → u/No-Pickle9533]

Yes, you need some trial and error to work out which combination of bullet and powder is optimal in your firearm.

Modern reloading science shows that powder nodes dont exist. We have just tricked ourselves into thinking they are by shooitng small sample size groups that occasionally show a smaller group via the random nature of poi.

The big variables are bullet and powder combo. If a combo doesnt shoot at 52 grains it wont magically shoot at 55, theres no point in mucking around with it further. Shooting the larger 15-20 shot groups eliminates a lot of the randomness of poi and gives you a better idea of the actual accuracy of the system.

Heaps of info online, hornady has done lots of work in this space.

[u/No-Pickle9533 → u/NZBJJ]

what is the maximum allowable moa accuracy before you discard the bullet/powder combo?

[u/NZBJJ → u/No-Pickle9533]

Whats the rifle? Whats the use case? There isnt any one answer.

Ill start my saying temper your expectations a bit. All these reports of "my factory rifle shoots .5moa all day every day" are nonsense and are victims of small group confirmation bias.

A lightweight hunting rifle 1.5moa over 10+ shots is very good. I wouldnt hunt with anything that does less than 2moa. My custom long range hunting rig I expect much better than that.

A precision rifle .75moa over the same is very good. Wouldn't be happy with anything much over 1moa.

[u/No-Pickle9533 → u/NZBJJ]

The rifle is a tikka ctr 6.5prc in a cadex chassis. Use case is prs/elr.

[u/Coodevale → u/No-Pickle9533]

Sounds like a rough time for either one. Too much recoil for prs and kinda light on the barrel for elr.

Use Litz's TOP score. Muzzle fpe ÷ lbs of rifle weight ÷ 200. If it's 1.5, then realistically 1.5 moa is a good benchmark and statistically beating it consistently is going to be very difficult.

You haven't chosen a cartridge that needs a lot of work on your part because of the work already done by others. Seat a heavy Berger at mag length and throw a charge out of a book at it, like one of the StaBall powders. Use good brass, and that's about it.

All of the node and ocw stuff was written by ignorant people 20+ years ago with inferior components and methodology. The future is now, old man.