Simple test: Size a case, just seat a bullet into that neck (1/16" or so) so it doesn't fall out, put jiffy marker around the 'fat' part or ogive of the bullet, chamber this case. Extract it and see if the bullet has gone further into the case with rifling marks on the marker or if it is the same as when it went in.
If there are no marks on the bullet, the throat is too long and this is the best that rifle will shoot...until it gets even worse.
The easiest solutions is to have the barrel set back so that a new chamber can be cut with a much shorter throat.
For max accuracy, the bullet must fully engrave in the lands BEFORE the ogive portion of the bullet leaves the case neck. If the bullet has to jump any distance, that is what I call freebore and it guarantees mediocre accuracy. You might get more velocity but you will rarely get tight groups.
Give that a check before spending anymore time with this rifle. If the throat is short, definitely look at bedding and free floating. Some factory barrels just don't shoot that well.
Jerry
