Technique for seating VLDs

[El Matador]

Getting ready to load up some 215 Bergers in the Win Mag that I haven't shot for a while. I measured some existing ammo with my comparator, and to my surprise there's 3-4 thousandths of variation in CBTO length. These were loaded with a standard seating stem, so I figure I need a VLD stem to minimize this.

Now I'm thinking about what the best way to get consistent seating depth would be. Or does a regular VLD stem do a good enough job? I made my comparator sleeve to match the bore diameter of a .308 barrel. On the Redding die the seating stem is .308" diameter. So the closer the stem gets to touching the critical area of the bullet the thinner the wall of the seater becomes. Do you guys have good luck with the Redding VLD stems or is there a better way to get consistency?

I'm using a Redding competition seater.

 

[ELR LVR]

Getting ready to load up some 215 Bergers in the Win Mag that I haven't shot for a while. I measured some existing ammo with my comparator, and to my surprise there's 3-4 thousandths of variation in CBTO length. These were loaded with a standard seating stem, so I figure I need a VLD stem to minimize this.

Now I'm thinking about what the best way to get consistent seating depth would be. Or does a regular VLD stem do a good enough job? I made my comparator sleeve to match the bore diameter of a .308 barrel. On the Redding die the seating stem is .308" diameter. So the closer the stem gets to touching the critical area of the bullet the thinner the wall of the seater becomes. Do you guys have good luck with the Redding VLD stems or is there a better way to get consistency?

I'm using a Redding competition seater.

Drill the stem I.D. close to the same size as your comparator hole
this will help consistency
the further back on the bullet Ogive that the stem makes contact the better
over making contact closer to the tip
--------------------------------
Be sure the tip of the bullet is not bottoming out inside the stem

 

[Link]

Same with me with my 6br. 108 Bergers. First, we anneal. I have gone to a larger bushing and using a mandrel, I give em a stroke with a brass brush to clean the inside of the neck. I think neck tension is the culprit. I go back and shorten the longer ones and use the shorter ones for sighters. I;m going to change seating dies next.

 

[Bill Norris]

Drill the stem I.D. close to the same size as your comparator hole
this will help consistency
the further back on the bullet Ogive that the stem makes contact the better
over making contact closer to the tip
--------------------------------
Be sure the tip of the bullet is not bottoming out inside the stem

Drilling the I D of my seating stem cured the issue with BTO variances.

 

[moondog]

Besides fighting bullet variation, different neck tension while seating will definitely mess with you.

 

[JFrank]

I just seated and checked 20 Dasher rounds only to find a select few that varied .0005, so It can be done.
I also had some brass that had been annealed that I was pretty disappointed with the seating consistency.

Go figure..

 

[Bill Norris]

Besides fighting bullet variation, different neck tension while seating will definitely mess with you.

Agree varying N T will play tricks on the seating die.

 

[Bill Norris]

I just seated and checked 20 Dasher rounds only to find a select few that varied .0005, so It can be done.
I also had some brass that had been annealed that I was pretty disappointed with the seating consistency.

Go figure..

I found if I try to anneal after every firing seat depth feel is not as consistent as I would like it to be.

 

[Straightshooter1]

Getting ready to load up some 215 Bergers in the Win Mag that I haven't shot for a while. I measured some existing ammo with my comparator, and to my surprise there's 3-4 thousandths of variation in CBTO length. These were loaded with a standard seating stem, so I figure I need a VLD stem to minimize this.

Now I'm thinking about what the best way to get consistent seating depth would be. Or does a regular VLD stem do a good enough job? I made my comparator sleeve to match the bore diameter of a .308 barrel. On the Redding die the seating stem is .308" diameter. So the closer the stem gets to touching the critical area of the bullet the thinner the wall of the seater becomes. Do you guys have good luck with the Redding VLD stems or is there a better way to get consistency?

I'm using a Redding competition seater.

Sort the bullets using a comparator that touches the ogive at the same place the seating die does. This can produce very consistent "seating depth" within each sorted batch. Just don't expect a typical CBTO measurement to be as consistent as the eating depth.

If you're seating VLD, it's a good idea to have a seating stem that's designed for them, or . . . do as Bill Norris suggests, "drilling the I D of my seating stem". Even then, sorting as I suggest should be followed.

 

[Jason D Hostetter]

Seat a third of the way, spin the round in the shell holder 180 degrees, seat the rest of the way, spin it again, run it back in the die again. Helps consistency and runout. If you're ocd.

 

[NCVarhtr]

Use a mandrel after sizing so the inside dimeters are consistent....Then a Use a VLD Seating stem,,....Never had a problem....

 

[JFrank]

Two of my favorite tools for seating consistency, a cordless drill for brushing and the accuracy one comparator, I only use the Hornday comparator to set the dies initially, after that the A-1 comparator will confirm the depth when I adjust the seater.

 

[El Matador]

Many thanks for all the great info! I'm going to try going a little tighter on my neck bushing and then expand with a mandrel. I will also brush my necks and modify the seating stem...or make a new one. Projects like that are good practice on the lathe.

 

[Clancy]

annealing, cleaning case necks with a nylon brush and using an arbor press will yield almost zero variation.

You do need a VLD seating stem.

 

[Cory porter]

Same with me with my 6br. 108 Bergers. First, we anneal. I have gone to a larger bushing and using a mandrel, I give em a stroke with a brass brush to clean the inside of the neck. I think neck tension is the culprit. I go back and shorten the longer ones and use the shorter ones for sighters. I;m going to change seating dies next.

What size bushing and mandrel are you using? Neck turned or factory brass?