Ancient.2hand,1hand swords

[cmo]

Hello, i have question regarding 83 lvl SOS of shillen knight and ancient sword (berserker 2 handed), it shouldnt give additional 100 critical rate from SOS ? Because if switch to normal weapon (not ancient) it gives me additional 100 critical rate.(f.e. Gram and Heaven's Divider). They are both counted as sword's but only heaven divider gives critical rate. Is it bug or it should be like that?