Correct. I'd buy bullet sample packs and change bullets as soon as the dispersion is "outside limits". You gonna know this inside 12-15 rounds.
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More or less. Some additional steps
Adjust expectations of what "good precision" is
Consider using a better measure for your precision (not entirely necessary if you shoot 10+ round groups)
If you want good precision, stack the odds in your favour and get a good system (rifle/scope) to begin with
If you want good precision, use the best components.
I had done that I thought tho I think I may have used too fast a twist barrel....So I have replaced it and am keen to find a good load with minimal round count on the relatively short barrel life of the chambering.
Ironically the best precision shooting rifle I currently own is also the cheapest I own ...Factory Howa bought second hand for 700 bucks shooting cheap gamekings and vmax.
TLDL: (if I listened correctly)
Seat bullet 25 - 35 thou off lands (although this not really important)
Choose bullet appropriate for your purpose (maybe have second and third choice)
Choose powders that will push bullet at MV required to do what you are trying to do
Shoot 10 shot groups with your bullet of choice but with different powders
Choose best groups, shoot 20 shot groups of each.
If still unhappy, change bullet, repeat.
If still unhappy, change barrel or change expectations.
That is an interesting article. I've just been to a conference where most of the papers presented focused largely on statistical methods. Statistical analysis requires a good dataset, and a sample size of 30 is where statistics start to become reliable and meaningful. It also empties wallets and bruises shoulders, potentially introducing a new source of higher standard deviation! However, there is still the cold bore shot that will deviate significantly from subsequent shots, and a sample if 30 of those will also be needed to fully understand that too.
Practically, you don't need big sample groups, if you only desire minute of pie-plate groups to knock down a deer at 100m. While you may not be getting the absolute best out of your rifle, it will meet your needs just fine. If you have OCD, or are a precision shooter, then statistics opens up a world of challenges!
Sort of. I would amend to say - test the bullet you want to use with the powder most likely to work, and if the result is acceptable - stop there and use it. "Best" or optimisation approaches are Sort of a waste of time and resources compared to an approach of just looking to meet a required standard.
I agree with Gimp.
With my flintlock I chose 3F powder and the bullet was round soft lead. I got it going at 1800 feet per second and can shoot three inch groups at 100. These were my premeditated standards - when I achieved them I accepted them. It took three shots. (It's a flintlock. That took an afternoon.)
A Russian taught me a saying once: "Perfection is the enemy of good enough."
You will notice in Benchrest there are a small number at the pointy end and a spread in the middle then a small number at the tail end.
While everyone "tunes" by adjusting powder, seating depth and neck tension some are better at it than others and some are better at reading the wind than others, and some barrels and rifles are better than others, also some bullets are better than others.
Given the "blunt" 6mm bullet all Benchrest shooters use, the wind does affect them and it's quite often you will see a 4&1 group with the 4 in a small hole and the 1 quite a ways away from the other 4. wind, handling errors etc can affect the group size.
Over the last couple of years I have seen where the winner shot a .5agg and the largest agg was 1.3", yes conditions, wind, rain etc do make a different to the results.
But with a good Benchrest rifle when tuning you can see the difference in powder, seating depth and neck tension by firing 3 shot groups and it's repeatable.
This is harder to see with factory rifles and a consistent .5moa out of a factory rifle is really good
As you say the records are outliers, but they aren't that far off the average winning aggs.
Most only believe what they want to believe, the best way to find out what a good Benchrest rifle does shoot like, and the difference seating depth & powder make is to experience it over several competitions.
Sums up my process too. If I dont get the velocity I want and accuracy Ill change projectiles rather than stuff around looking for some magical thousandths of an inch or .1gr of powder.
I used to think I was charmed as my rifles always shot as well or better than my mates who spent hours working this stuff out. Turns out I am probably just part of the noise.
I suspected Santa wasn't real