In my 338 Lapua Imp I use N570.
I use the same load as 2225/Retumbo but N570 gave more speed.
I use Lapua brass as it can take more punishment.
I have a 33.5" barrel & looking at the brass I push a wee bit hard.
The primers still fit nicely.
I get 3080-3100 with 300 Scenars.
I have tried the Gen1 Bergers & the SMKs but haven't got the results I would like.
I may do more testing or wait until the Gen2s get over here
It is very accurate & I have shot it out to 1370 with first shot hit as well
It is a fairly light weight rig with an AICS stock & a Nightforce.
If I put it in a Mc Hunter edge stock & MK4 it weighs under 11lbs a nice hunting weight.