Thread: 6.5 cm case capacity

Started load developing for my tikka strata 6.5cm. Using Berger 135 classic hunters. Using Norma brass.
Berger website load data says they're getting 49.8 gn of reloader 26 in the case, 105% case capacity and thats giving them 2977 fps. I started loading but can't get past 48.0 grains and the compressed load is too much to hold the projectile.

Seeing if any of the knowledgeable lads out there have any suggestions as its not quite the speeds I'm after at 48 grains.
Have herd that sometimes Winchester or Lapua brass can give better case capacity as its thinner walled? Can anyone confirm this? Any ideas are welcomed with open arms hahahah.