finally learning the importance of seating depth

[Mikecr]

You don't need to shoot beyond 100yds to do Berger's full seating testing. I'm confident those who have actually done it have seen how it opens/closes grouping, and that it's very easy to discern better/worse -at any distance.

 

[gohring3006]

You don't really 'tune' with coarse seating. You tune with powder.
That is, you can't just pull a powder charge out of your butt, and tune the gun with seating alone. In contrast, you can fully tune a gun with powder, regardless of seating.
Yet, seating can open and close grouping way way more than powder. Anyone who's ever done FULL SEATING TESTING (Berger's recommended) has seen it.
And this shows seating and powder being separate and different.

Best coarse seating is prerequisite to best results. If you're not in tune while at best seating, then overall results won't be the best possible. This is usually obvious.
But if you're not at best seating while at tune, you may think you're results are best possible. Problem being, there is a chance that it's not.

Again, finding best coarse seating is not tuning. In fact, it's best done as far from tune as possible. Seating testing is for clearing a detrimental condition -that is bad seating for the bullet/throat. Change either one, bullet or throat, start over to find best seating.
This, having nothing to do with powder.

20+yrs ago I argued this with BR folks who insisted that VLDs had to be in the lands to shoot. I tried to get them to understand that best seating could anywhere else. They just needed to do full seating testing to see it. And while everyone claimed they did seating testing, and that everything shot best in or near lands, the truth was that they never did full seating testing -ever.
What they were doing was pulling a starting seating out of their butts(assuming it needed to be close to lands), then tuning with powder, and tweaking seating in a narrow sense while at that tune.
Well tune is an amplified condition, and tweaking seating much from that serves to cause a falling out of that condition. Something always seen as going in a bad direction. So within ~20thou of seating they had tuned at, they gave up, declaring BS on my notions. After all, 20thou seemed a huge way to go with seating, and things never got 'better'.

I realize that for ~100yrs everyone tuned with powder, and tweaked seating for shaping. And all of them had guessed about initial seating to begin. Relatively few did a broad, full seating testing to begin.
I couldn't get anyone to do it.
It wasn't until Berger put out a seating testing procedure that the light bulbs started coming on. But some bulbs are just not lighting I guess.
So I suppose Berger will have to explain to folks what seating is actually doing, before more folks understand what I've been saying for decades..

That's why I always start with seating first then powder. I've been in arguments with several people including people in this site, saying my method is wrong. All the while, Berger's seating method is posted here in a sticky. Lol

 

[rockwallraider]

Lets be sure we get our decimal places correct, 0.150 or 0.0150. I think we all know what you meant. A friend reloader likes 0.010 off the lands for his Hornady bullets in his RPR.

Meant .150

 

[Mike 338]

started reloading about a year ago and have never really messed with the seating depth of bullets, i typically just left them 20 thou off the lands and if it I did not find a good load would assume did not like that bullet. Yesterday I was doing the same for my 6.5 sherman short and for fun decided to try bergers suggestion on seating depth with the 140 vld bullet. glad i did. this particular barrel like the .150 off the lands. No telling how much time I have wasted as I would have never pushed the bullet in that far in the past.



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My questions would be are most bullets this sensative to seating or are the vld's that much more extreme?

Thanks for pointing that out. Most folks never develop a load to it's potential because they believe they have to be close to the lands. IMO, "most bullets" are a big unknown. You just never know till you test them. I do a rough seating depth test very early on in load development, right after determining max-charge weight.