Bullet seating depths; VLD Berger Hunting question...

[19mad81]

Hello gents, I have a question for you reloading gurus as it pertains to bullet seating depths.

I have a .300 Weatherby Mark V, Custom Shop and found what I believe to be a descent load using the Berger 185gr vld hunting bullets. I am now trying to close in on the groups I have by adjusting the seating depths per the Berger book.

My question or problem I have came across is the weatherby freebore is substantially long and I am not able to get close to the lands as suggested. The book suggest to back off the lands .010, .050, .090, .130 until one load shows the potential your looking for...then to adjust accordingly.

My bolt face to land measurement, measured out at 4.010 and the COAL Is 3.560, that being said subtracting the suggested measurements from 4.010, I end up no where close to the COAL. it also suggested that the weatherby rifles prefer the jump over the jam...what methods have you guys used or what suggestions do you guys have for adjusting the bullet seating depth so I can tighten my groups up.

Freebore gap is .361
Bolt face to lands 4.010
COAL 3.560

 

[Hookturnr]

I have had success in the past with running the same seating depth test starting at max. mag length and moving in until I found a sweet spot. You don't have to jam Berger VLD's, in fact they prefer some jump in some rifles. Go ahead and run the seating depth test starting at max mag length and getting shorter using the same protocol as if you were jamming the lands.

 

[19mad81]

I appreciate the advice, sounds like a game plan. Other than seating a test round and making seating adjustments, do you have another way of determining the max mag cartridge length...