This just happened to show up on Google as recommended for me.
Kudos to the author for putting in some serious time and round counts to investigate this and not just jump on board or poo poo the ideas. Also Kudos for the author for being a man who can actually write an article well. Seems like that’s a skill that’s being lost these days.
Of course not even 5 minutes after finishing this article I get on YouTube and the first thing I see recommended for me is Cortina interviewing one of his partners and discussing the importance of super small changes in seating depth, powder charge.
Well, he said it early on in the article; repeatability is the thing you are looking for in a load.
Repeatability at 100 yards for basic load development.
Repeatability of POI for the load; cold barrel and successive firing.
Repeatability at distance of group integrity - 300, 600, 800 yard testing.
Repeatability under changing environmental conditions of temperature, humidity, etc.
I agree with his thought on the COAL being used versus chasing seating depth perfection. Almost all of my handloads are set at the same factory COAL for a given bullet; back to the large sample point of reference, the ammunition companies have fired millions of rounds, so it is logical that the COAL they use for a given bullet / caliber will work across the largest group of weapons designed for that round; not all, but most.
The seating depth question is answered best by the benchrest community; where the consistent winners do adjust the seating depth, and for most it is touching or actually soft seated into the lands. For their discipline, the smallest gains do matter, and with that they, above all other shooters track those incremental differences the most. Other shooting disciplines don’t necessarily win by 1-10 thousandths in aggregate group sizes (like PRS), and it doesn’t come into play really in hunting scenarios. The other factors of knowing your weapon, the ballistics of the round, shooting in the wind, and actually spending time on the system before you launch rounds on animals at distance; are the factors that drive hunting results (see 600 yard gallon jug challenge)
I did notice that in one of his samples, unless I read the data incorrectly, that the charge sample only covered 1 - 1.5 grains in tenths of grain increments, so not sure I would call that a significant enough charge weight change to measure that particular metric; changing by 1.5 - 2+ grains or more for each load would say more.
Good article though and the shooting community is always learning from a diverse set of data.
You bring up several excellent points including the fact that Hornady is not the only company out there making bullets and doing testing. I highly doubt that Barnes, Berger, Nosler, Speer, etc, etc Just Whipped up a bullet design and then did a three shot group and called it good to go. They almost certainly shoot thousands and thousands of rounds themselves. And they all give different advice about how to do things based on their observations.
Barnes and Berger both recommend doing seating depth testing. However Barnes says their bullets tend to like more and more jump while Berger says they are bullets like to be much closer to the lands. They both recommend fairly large seating depth adjustments compared to what you read about on most of the reloading websites or videos. Yet Hornady and Hammer both state their bullets are not jump sensitive.
Agree that more and more testing is needed to be done. And hope that it’s done in a nice and open fashion like this article did where we can actually look at the data itself and make appropriate critiques.
If a rifle doesn’t perform well with a standard bullet/powder combination at a reasonable velocity I think that getting a new barrel (or a new chamber cut) is a perfectly valid option rather than spending a ton of time and components trying to find a possibly imaginary sweet spot; if it doesn’t shoot that standard loading well its also very likely that the rifle just has inherent issues that no amount of load dev will fix. For example, if a .308 doesn’t shoot well with something like 175gr SMKs and Varget for me, is it even worth my time trying to find something that works over a $5-600 prefit barrel? This is especially true as the “standard” combinations of powder and bullet are usually easier to find in stock at decent prices than something more obscure.
I think it might be worth spending a little time in load development. I have a Savage .308 that was shooting 1.5"+ with all the factory ammo I tried. I spent a little time developing a load for the gun and it is now shooting just sub-MOA.
Use a powder known for generating consistent results in a given caliber and bullet weight / design.
Use load data that is referenced by shooting history / references as generally successful.
Change the powder by itself first, either up or down, by .3 - .5 increments to see changes in group sizes.
That often produces a high node and a low node where the barrel is vibrating at a level of consistency reflected by grouping.
The quality of the barrel is a large determiner in the ability of a rifle to produce good, consistent, groupings. Rifles that cost less can produce very good groups, but it may be harder to find that combination, and custom barrels generally are easier to find the right combination…I own both and those are my observations.
Finally, accurate and consistent groups are an aggregate of a lot of factors, and no single step, item, or technique will guarantee results in a rifle, and definitely not across different rifles. I still have a target I shot 10 years ago; had a new custom barrel put on a factory stock, action, and trigger; made 10 hand loads, changing the powder by .2 -3 grain increments, and the rifle shot 10 x 5 shot groups in a row that were .650 or better. I have never had another rifle of lesser or greater value repeat the same level of accuracy as that system. It is a challenge to find a certain level of accuracy in a rifle sometimes.
Good luck