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Squarbridge - most of what you're doing will keep you out of trouble. Unfortunately, reloading is a technical undertaking and one should learn about pressure, what makes it, how to read and measure it and proper ctg. 'fitting' to stay out of trouble.

Your quote above shows you don't understand what is happening when primers back out of the ctg. case (as long as you aren't talking about case head and /or primer pocket expansion causing loose primers). Primers don't back out of the case because of too high pressure. They back out of the case due to an excessive headspace problem, either due to excessive headspace in the chamber or excessive headspace caused by the loader. This is caused by the loader due to improper die setting in the press, usually from setting the dies to touch the shell holder. With the .30/06 and the 7x57, you do not have to touch the shoulder with the die - ever. Partical FL sizing is all that is necesary for proper fitting ammo. Both the 7x57 and .30/06 have relatively long necks for holding the bullet securely and only need all but a 1/16" of the neck sized (actually less neck sizing than this is necessary) Adjust your dies so you can visibly see a false shoulder in front of the case neck/shoulder junction and your primer backing out will should stop with normal high medium loads.

When the firing pin hits the primer, it pushes the case forward in the chamber if there is room to move. The powder burns and pressures exerted on the case walls hold the ctg. in this forward position, but the primer backs up against the bolt face while the bullet departs. If the pressure is high enough, it overcomes the brass's ability to adhere to the chamber walls and pushes the ctg. back against the bolt, reseating the primer, flattening it somewhat and the brass stretches forward to the shoudler of the chamber filling that empty space all this while the case is fully supported by the bolt face. This is what is supposed to happen the first time the round is fired. If the pressure is not high enough to cause the case to stretch, expand and fill the chamber, the primer alone is pushed back against the bolt face, with shows up as a protruding primer. Reducing the pressure further is not the cure. Because the pressure was too low to re-seat the primer, increasing the load to generate normal pressure is the solution to primers backing out.

Reducing the load when you see a primer backed out, will not get you into trouble, but will cause you to load very much sub-standard ammo. Pressures in the relm of 35,000PSI generally don't re-seat the primers. The '06 and it's childred are fully capable of handling and do handle pressures in the 55,000PSI to 63,000PSi range - this is normal. Factory ammo is loaded to these levels and the handbook data generates these pressures with top-end loads.

Every handloader should have his/her own chronograph in this day and age. They are cheap and are a valuable tool used in conjunction with other tools, michrometer, calipers, etc in loading good, safe ammo. Learn to use the chronograph to properly access your handloads - more problems than solutions occurr with lack of knowledge or disinterest in that handloading knowledge. For people who don't want to know what is actually necessary to know, I suggest factory ammo.

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Daryl

"a gun without hammers is like a Spaniel without ears" King George V

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