The OP is referencing powder charge. Is that a part of the guns tune? If you believe the target the bullet gets there for about 28" internal and how ever many hundreds of yards external. I would say this makes it a bit hard to tell what is making the difference.
I would agree, but would think it would not make a difference even for those shooting .1X groups at any distance to realize.
Erik talks about how good John is but will not share the info to public.
Absolute pressure is preferable to me. The rest are simply modifications to best understand what it means.
I see it the same and I think smaller numbers are worth using too, in regard to pressure. Most station reporting centers can give station pressures to more resolution than the Kestrel. I'm still learning this aspect too but I've tested a fair amount. I just prefer not to claim anything as fact yet. I do think we can get really close to tuning by likely temp and pressure, combined. Thing is, I think it'll be very close most of the time anyway...4-5 marks on my tuner but there's still variables that I haven't pinned down enough to say that 1 mark equals x degrees at x pressure, sort of thing. Since you're close anyway, I'm not sure how much there is to gain but it might be enough to worry with, if the program can be refined to the point where it's of significant benefit, consistently.
IME, tuning is maybe 100% about exit timing and muzzle position. I think if one way works, so does the other because both are ultimately doing just that, affecting exit time with muzzle position. There is more to it than that and that's an oversimplification, especially in regard to load workup.
Smokeless powder turning from a solid to a gas is a chemical reaction. ALL chemical reactions are somewhat temperature dependent. This isn't internet gossip but science. So, using only pressure can't be done becuse it's only one variable. If there are only two, temp and pressure, then yes, getting very close is doable but you're gonna have to do it based on the effect of temp on various powders, over various temp swings and in various cartridges..because all of those things matter to how powder burns, too. Been there and done this for several years now. There is no easy button yet. Handloaders have been trying since we started loading for accuracy, I would guess.
Tuners are not a fad. They've been around and have numerous world records and national championships...and the science does support the results. But there's also a lot of bad info out there and they are often misunderstood and used improperly. They're really very simple to use but but all too often, they are moved wayyy to far at a time or similar and without a truly methodical approach. That's the key right there. Settle on one that the maker can walk you through every detail with, in regard to setting them as well as the whys and what fors. There is absolutely no doubt whatsoever in my mind that they are for real. None, nada! There's also no across the board generic way to use every tuner on every gun and that leads to confusion when people want a simple and easy solution to everything. In other words, you can't necessarily use instructions for tuner A with tuner B, and so forth, even if the instructions are good for one or the other. So people google up the "simple" answer for setting their tuner and can get mixed results, which makes it a bit of a challenge if that's how you get your info. Again, just settle on one that the maker can and will walk you through well and you'll likely be very happy and wonder how we ever made it without one.
Would DA not affect external ballistics more than internal ballistics?
Then simply move on there skippy. Just skip on by next time. Tuning by da or whatever is still tuning. If it works for one method, it'll work for the other and adjusting by DA isn't new, so I'm not sure what you meant by "next great thing." Either way, gain something, share something, or move along. No harm intended on my part from my post and the op implied that he's familiar with tuners in a previous post but it might've been missed when he said, "so it wasn't down and out." I knew exactly what he was referring to and I answered. And yes, that's tuner related. Are you looking for an argument? I'm not.
John shot F-Class
There's also another John Myers. I think the spelling is different. One shoots short range group and score and might dabble in some long range as well. The one I'm referring to is I think in Indiana, near the Ohio border somewhere. I may be wrong but I think he has mentioned to me, him tuning using DA. Maybe he'll see this and reply. I might be incorrect but there are two and I don't know which the poster was referring to. He's a good shooter
The one Erik refers to comes from a racing background and related his testing methods from there to the tuner as well.
