Srp vs lrp.

[SouthLoganCountyShooter]

Picked up some Peterson 308 srp. Did a velocity test with srp and srmp. Using tac and 124hh. 47g with cci200 and starline brass I'm at 3250fps.
I loaded 47g tac with the Peterson brass with cci srp and srmp. Velocity was just over 3000. is this normal. Srp 3007 -3015 srmp 3009- 3016.
Do you usually loose that much velocity?

 

[wldcat]

My first thought would be the difference in brass? I am guessing the star line brass is thicker and therefore less capacity and in turn more pressure leading to the higher velocity. I haven't tested large vs small primers in the same cartridge before though, so hopefully someone else chimes in that has tested this.