Quote:

---

I got the CH4D neck sizing insert die and squeeze the .303 British necks down to hold a .304 180 gr. Hawk Bullet. I used beginning load data for a 180 Gr. Sierra bullet and loaded 3 rounds.

Went out to the range this afternoon and fired the three rounds.

No problem. No pierced primer, no head separation. Brass fired, extracted and eject easily.



When I got home I tried to insert a .311 bullet into the fired case necks and it would not go.

Now to build some loads for the this gun.

---

Wow!
Those ordinary .303 British 174gn FMJ must have had a long ogive, enough to just chamber DD.
They must have raised the pressure quite substantially to say the least!
For some reason I just can't grasp why the first cases almost separated; these last lot don't appear to have protruding primers or show excessive headspace.........what am I missing here?
Great to see that you have it going mate, no wonder you were chaffing at the bit!