.300 Win Mag Lapua Case Observations

[SOSNBA]

I just got some Lapua brass in.300 win mag. They are extremely high quality and consistent vs other more common brands. I hear they last longer (primer pockets in particular) so that should offset the higher cost. Besides being heavier by about 15gr , I measured the Lapua H2O case capacity on an unfired brass at 89.2gr. For comparison, an unfired Winchester case was 90.0gr, fired Winchester case in my rifle was 92.2gr. Flash holes and primer pockets look great. The Lapua brass is also a couple thousands bigger near belt and wide portion of shoulder. Given the reduced case volume, I plan to lower my powder charge a bit more than normal to start load development with Fed 215 primer, H1000 powder and 225gr ELDM bullets..

its going to be a while until I can do load development but thought I'd provide these initial observations.

 

[SOSNBA]

Update. I had to back off powder charge by 1.3 grains of H1000 with same 225gr ELDM and 215 primer to achieve same velocity with Lapua vs. Winchester brass. Both fired on same day, same rifle.

 

[FredHammer]

What was the fired Lapua case capacity H2O?
PPU 300WM is fired H20 Capacity 92.5gr ave.
242.5 weight with fired primer still in pocket.

I read on another forum ADG fired is 92gr H2O
I'd like to compare with Peterson too.

 

[SOSNBA]

91.6g H2O fired. IIRC.

5 warm reloads so far (2920fps w/225gr ELD using H1000 in 26" krieger barrel with longer, tighter diameter freebore) and primers are tight. So far so good