Got my buddies .303 P14 fininshed (.308" groove diameter). He'll be loading up his new brass with IMR4320 and 220gr. Hornady .308" RN's and we'll test this weekend. The chamber has minus .003" shoulder headspace on new Federal brass. Bolt drop is easy as the brass moves this .003" without protest. Reason I chambered it this way was to prevent any stretch at the web upon initial firing.

The factory reamer, which is ground for headspacing on the rim, cuts a chamber with at least .020" headspace on the shoulder. No wonder .303" brass is known to separate in just a couple loadings. Keith's bras should last 20 to 30 - maybe more, depending on how he loads it.

So - due to the shortage of good 215gr. bullets for the .303 here, buddy keith now has a rifle that shoots factory .303 perfectly yet also handles .308" 220gr. RNs - it was made for them.