308.....you probably would have solved it by going taller rather than wider.........you have to get flue warm/hot so it draws air/smoke up it...hot air rises,cool air goes wherever the heck it wants.......just about every open fireplace Ive ever seen that smoked was fixed by rolling a sheet of corrigated iron and poking it down the chimney hole to increase height by 6' ish....turns a smokey dull fire into a roarer... the modern hats on logburners are designed to SLOW down the airflow....thats why the older kent type fires went like crap when they were fitted,,,,,,fire just cant vent smoke fast enough to draw properly,take the hat off and put older more open type on and fire goes properly again.
Bookmarks