Thread: What would have this felt like?

Greetings ,
A bit more detail. The headspace dimensions of some of the rifles and dies and chambers I have encountered may be of interest. Cases FL sized in recent Redding dies move the shoulder back 0.3mm (0.012") from fired position in my and a friends. For my M38 and a friends Ruger it is 0.45mm (0.018"). With an older set of Lyman dies it is even worse at 0.4mm (0.016") and 0.55mm (0.022"). Unfired Lapua cases are a good match for my Tikka. So the problem exists in the US. Somewhere along the line US die makers started using dimensions that were too short and this was only partly corrected when the 6.5 became a SAAMI cartridge.
This means that even with the tighter T3 chamber cases sized with the die hard down on the shell holder headspace will be grossly excessive, especially with older dies. When a cartridge is fired in these chambers the firing pin fall plus the primer igniting forces the case to the front of the chamber with the primer backed out hard against the bolt face. As pressure rises the case is forced back over the primer flattening it as shown in the photos. This happens even at some start loads.
Around 60 or so years ago Julian Hatcher wrote in American Rifleman that primer appearance was practically worthless for judging pressure. Others have repeated this over the years based on their experience. I am with them on this one.
Regards Grandpamac.