I am loading 308 and am trying to step up a notch in terms of accuracy so am developing a load with Lapua brass and the 155gr Scenar.
Making dummy bullets to check consistency of my process.
My process is:
Nudge the shoulder back by 2 thou with Redding full size die and a redding 6 thou shellholder
Back to normal shellholder
Decap and initial necksize with Lee Collet die.
Trim with Lee hand trimmer, Debur and chamfer
Lube and neck size half the neck with RCBS neck sizing die and a 336 bushing
Clean and check neck runout on RCBS gauge.
Seat bullet with Forster Benchrest die
Check runout at 1) bearing area infront of neck and 2) half way down ogive.
OK
So made 2 bullets (! its not scientific but it highlights my problem perfectly)
#1 Case Neck runout 1 thou Bearing runout < 1 thou Ogive runout 1 thou
#2 Case neck runout 1 1/2 thou Bearing runout 4 thou Ogive runout 9 thou (reseated bullet and this reduced to 5 thou)
So:
What runout tolerances should I expect to achieve given this process?
I have had this inconsistency before and can't isolate it, what should I look at?
How sensitive is the seating process in one of these dies to initial bullet/case alignment?
Where should I measure runout?
Thanks
Andy
Making dummy bullets to check consistency of my process.
My process is:
Nudge the shoulder back by 2 thou with Redding full size die and a redding 6 thou shellholder
Back to normal shellholder
Decap and initial necksize with Lee Collet die.
Trim with Lee hand trimmer, Debur and chamfer
Lube and neck size half the neck with RCBS neck sizing die and a 336 bushing
Clean and check neck runout on RCBS gauge.
Seat bullet with Forster Benchrest die
Check runout at 1) bearing area infront of neck and 2) half way down ogive.
OK
So made 2 bullets (! its not scientific but it highlights my problem perfectly)
#1 Case Neck runout 1 thou Bearing runout < 1 thou Ogive runout 1 thou
#2 Case neck runout 1 1/2 thou Bearing runout 4 thou Ogive runout 9 thou (reseated bullet and this reduced to 5 thou)
So:
What runout tolerances should I expect to achieve given this process?
I have had this inconsistency before and can't isolate it, what should I look at?
How sensitive is the seating process in one of these dies to initial bullet/case alignment?
Where should I measure runout?
Thanks
Andy