I'm reloading very carefully and unfortunately the velocity standard deviation and velocity extreme spread varies inconsistently from 7.5 fps to 60 fps - it's just all over the place and unpredictable.
I'm sure you'll want details so here ya go.
cases: new or once reloaded Hornady
bullet: .223 Rem Nosler 70 gn RDF
powder: Reloader 15 and Ramshot TAC
primers: Federal GMM
procedure:
sort cases by weight
resize cases with Hornady Lock N Load Match dies with 0.254 neck bushing
measure and trim cases as needed to 0.002"
light chamfer mouth inside and out
uniform flash holes
prime case
dispense powder from RCBS Chargemaster
confirm weight on beam balance scale
load powder in case
seat bullet to 2.26 COAL to fit in AR mag, although the mag goes in a MVP LR
Then measure the case to ogive and seat every bullet by that measurement to within 0.002"
Check/set concentricity to no more than 0.002"
Imagine after all that, getting SDs all over the place from 7.5 fps to 60 fps - completely unpredictable
The gun is a Mossberg MVP LR with (and without) a Liberty Triumph suppressor - suppressor on or off doesn't seem to make any difference.
I thought maybe the bullets are getting set back by chambering, so I very carefully hand loaded 3 sets of 5 rounds into the chamber and closed the bolt . I saw no difference.
What in the world am I doing wrong?
Many thanks for your help and thoughts!
I'm sure you'll want details so here ya go.
cases: new or once reloaded Hornady
bullet: .223 Rem Nosler 70 gn RDF
powder: Reloader 15 and Ramshot TAC
primers: Federal GMM
procedure:
sort cases by weight
resize cases with Hornady Lock N Load Match dies with 0.254 neck bushing
measure and trim cases as needed to 0.002"
light chamfer mouth inside and out
uniform flash holes
prime case
dispense powder from RCBS Chargemaster
confirm weight on beam balance scale
load powder in case
seat bullet to 2.26 COAL to fit in AR mag, although the mag goes in a MVP LR
Then measure the case to ogive and seat every bullet by that measurement to within 0.002"
Check/set concentricity to no more than 0.002"
Imagine after all that, getting SDs all over the place from 7.5 fps to 60 fps - completely unpredictable
The gun is a Mossberg MVP LR with (and without) a Liberty Triumph suppressor - suppressor on or off doesn't seem to make any difference.
I thought maybe the bullets are getting set back by chambering, so I very carefully hand loaded 3 sets of 5 rounds into the chamber and closed the bolt . I saw no difference.
What in the world am I doing wrong?
Many thanks for your help and thoughts!