I've been mulling this since the original thread and am not sure I've got any answers. Previous posts are certainly all good info, but when a double shoots into two inches and then a bit later is shooting into eleven inches with vertical dispersion, with what we assume was the same load, I assume that it has come off-face in between. A Jeffery boxlock .475 No. 2 that was left with a friend and I to develop a load for didn't shoot worth a damn the first trip to the range. Going over the gun carefully, I discovered that it was slightly off-face. J. J. put it back on face and then it shot just fine. Sure cured the vertical dispersion.

Emory said that J. J. found that the rifle was off-face. Hmmm. Westley built this rifle on a PHV-1 action "bought in" from Webley & Scott (this one isn't of the typical Westley C-type). In a discussion with J. J. about another rifle a while back, he indicated that he rarely sees rifles with this action off-face. I can remember seeing one that had been re-jointed, but have never seen one that was actually off-face. Maybe I'm wrong, (interested to hear observations of others) but my impression is that this action is particularly resistant to the development of this condition. The "bulged" chamber is either bulged due to a violent overpressure load, or has been honed. If due to an overload, that might help explain how this piece got off-face.

Handloading isn't required to get an overload that violent. In all of my double rifle shooting over the years (I've almost always shot only my own handloads), I've encountered overloads violent enough to really scare me just twice. FACTORY ammo both times. We're talking purple-stripe double proof stuff of the fragmentation variety here guys. Ammunition of both makes is still in the marketplace and I know of one nearly new .500 Nitro that was blown up with one of them. I no longer shoot factory double rifle ammunition, unless it comes out of a red and yellow box that says "Kynoch" on it.
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