Sorry, didn't realise you meant blitzking.
So yes, i did use 55s blitzking in my old .223 with very good results. And the 100gr gamekings in my .243. As above, I don't think you can go wrong with Sierra bullets. Its the make (along with lapua brass and viht powders) I suggest people go with when they start reloading.Not with a howa but when I couldn't get 52gr Amax bullets I used the 55 sieras and they were acceptable. But not quite as good as the amax.
I now have a 1:8 and use the 69grs which are great and I've always used sierra bullets in my .243 and .308. I like they are consistent and always well made.
It is going to be interesting to see how the new sierra bullets with plastic tips shoot. Hope they aren't just in .308.