Time to chat some BR

Lawrence W. said:
Hello Dave.

I beg to differ. If I had been shooting score and as I had less than 1 bullet in vertical, I would not have played with the seating depth and I would have centered the vertical over the dot. The tune in the 1st group would have been sufficient to shoot a 250-25X with somewhere around 10 wipeouts. The final tune would have produced a 250-25X with around 15 wipeouts.
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This might be true IF you don't have to move the rifle but when one has to move the rifle around a score target other variables enter into the picture. The first two 250-25's were shot with a 6 PPC by Dennis Collins, I believe. I don't think there have been many, if any shot with a 6 PPC since then but the current record of wipeouts is held by Al Weaver with around 20. It ain't as easy as it looks or there would be a lot more 25's and would have been a 25 wipeout long before this and ther are a number of HOF Groupers who shoot Score with some regularity.

All of that aside, why would a lad settle for any vertical if they could take it out?
 
Pete Wass said:
All of that aside, why would a lad settle for any vertical if they could take it out?
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I agree with you. That vertical was driving me nuts all weekend and I had tried to get rid of it with powder. It took me 3 aggs before I tried changing the seating depth. Just wanted to remind everyone about the impact a small change in seating depth can have.
 
To add to what Pete said in Post #21, I believe Al Weaver had a 250, 25x & 21 WO'S. I just spoke with Al this past Sunday about this.
 
A thin coat of Prussian Blue is what I use to find "just touching".

Take a Q-tip, and reach up in and smear a thin coat in the throat area, seat the loaded round. Move it in a few thousanths at a time till you see nothing. That's pretty close.
 
Worked out the logic on this a long time ago. Given that I refuse to shoot with difficult bolt closure (unless forced to) I start with a case the has tight neck tension and seat a bullet far enough out to make the bolt hard to close. I then adjust the seater until the bolt closure becomes just barely tolerable. From there, I only have one direction to go and let the rifle tell me where to stop.

One thing for certain. It's plain wrong to believe that there is a "standard" seating depth.
 
Just my 2 cents...

I use a split neck case. One that will hold the bullet, but doesn't have enuf tension to make it stick in the lands. I seat it long so that the rifling pushes back the bullet, and of course I close the bolt. This measurement should be where the lands start. This is the way I start my seating depth when tuning, and then of course I go out .003 at a time.

.003 I agree is a large change in seating depth especially with the 4-groove cut rifle barrels. I don't recall .003 seeing as much of a change in the 6-groove button rifle barrels. I could just be trippin' tho. :D Just my 2 cents.

Matthew S Keller
 
It amazes me

Exact seating depth hasn't been a standard part of Benchrest loading for all this time. I guess when one looks at how long folks figured thrown charged were "Good Enough", the seating depth thing would be below that somewhere. We have been fortunate to find barrels that will shoot anything we throw together to shoot in them.

In my opinion, folks have placed too much emphesis on their brass. Prepared Brass is simply a container for the things that truly matter, the exact amount of fuel and bullets presented to the lands exactly where they need to be.

Another issue is Seating Stems. Some bullets shoot better then others, usually because they have a more uniform Ogive slope length. It makes no sense to have seating stems touch the bullet far from where the bullet will touch the lands. Seating stems need to be construcetd so that they engage the bullet just above where it will touch the lands. If we could get them, folks would find that a lot more bullets would shoot a lot better than they did before.
 
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