Does anyone see any problems with a takedown in both .275 Rigby/7x57 and .318 Westley Richards?

The case head is similar enough. I already have a quantity of .318 WR brass, believe it or not. But .30-06 brass can also be used I believe.

I would think the cartridge length would be similar enough. But the length of a .318 WR with 250 gr projectiles. how different would that be?