A friend of mine has a Howa in .223 Rem. A light barreled gun. It will put 3 shots at 100 yards around 1/2", with handloads using the 40 grain VMax, pretty consistently. The other few Howas I have seen have shot quite well. None were even remotely as inaccurate as yours is.
On the other hand, his heavy barreled Savage FVSS in .223 will do slightly better, or I should say did, around .300", until his grandson put 250 rounds of Wolf ammo through it. After that, the best it would do was slightly over 3" groups at 100 yards, with the same handloads. He's still working on cleaning the bore and trying to get it to shoot well again. Needless to say his grandson won't be borrowing any more of his rifles.
Maybe your problem with the Howa is of a similar nature. It could be if it was a used gun.
