Moving from Winchester to Lapua .308 Brass in F-Standard

[AlanBT]

Hi All,

I am switching from Winchester to Lapua Brass in my .308 F-Standard Rifle.

My Winchester brass weighs 154.4-156.0gns across 300 cases and I'm moving to Lapua at 173.4-174.7gns across 400 cases.
I currently use 45.3gns of AR2208 for about 2930ft/sec (yes I know it seems a high velocity for that much powder, but that's what the Chrony tells me)

Logic tells me I should be loading lighter in the heavier brass for the same velocity due to higher case pressure.

Does anyone have a rule of thumb or equation that would tell me what sort of load I should try in the Lapua or do I just: a) load it the same and go with it, or b). Do the whole load testing thing again?

Thanks

Alan

[jasmay]

If you know your velocity why don't you just load up a spread and measure until you get the same?

There is no hard and fast rule of thumb, I did this and had to add .2gr when moving from lap to Winchester.

[AlanBT]

Thanks Jasmay,

This is useful.

Alan

If you know your velocity why don't you just load up a spread and measure until you get the same?

There is no hard and fast rule of thumb, I did this and had to add .2gr when moving from lap to Winchester.