How old is you Dad's 223? I ask because newer Savage 223s have longer throats than say 15-20 years ago. I have two Savage 223 rifles, one purchased in the early-90's, and one this year. The new one has a throat 0.050" longer than the old one.
Best and cheapest way to find out is to make up a dummy round with about 1/2 of the neck sized, start a bullet in it, and chamber it hard to seat the bullet into the case by the lands. Measure the length and deduct 0.010" or so to get a max length, then deduct your 0.020" from that.
The 0.010" deduction is an arbitrary number to allow for depth the bullet was forced into the lands, which you will be able to see on the bullet. It might be more, or less, depending on the angle of the reamer at the lands starting point. If you measure those marks on the bullet, and deduct that amount from the original reading, you will have a OAL that is just barely at the lands. Might even be lightly touching them.
Bookmarks