What common calibres are in the UK?

[Mortblanc]

And do remember that in GB you have the benefit of having all your firearms proofed during production. Every firearm has been tested and proven to stay intact when fired using a cartridge overloaded from the MAX standard by 30% and in some cases even more.

When you are using a shotgun that is rated for 3" magnum loads and you are following load data that is for 2 3/4 light field shells a slip up is still way inside the safety margins of your shotgun.

Much of the "book data" produced today is also very conservative due to liability issues. I have some old Speer and Seria books from the 1950-60 era that list loads for center fire rifle that are 20% over max loads in today's data publications.

Even in the more recent publications the data varies between publishers. My Lyman and Hornady books show max load for a 115gn 9mmL bullet with a 20% difference in charge of the exact same powder. Even then the truth is that they are both well under the military load in the same caliber.

I own one rifle that offers the same receiver chambered for every cartridge between .223 and .338 Lupea magnum. Should I really be losing sleep over a slight overload in .223?

The chances of one blowing their firearm up are somewhere between slim and none if you are using good sense and loading conservatively in a survival situation. Most reloaders are aware of their risks and taking the necessary precautions with each pull of the reloading lever. It is the guys with the automated units pumping 600 rounds per hour that I worry about!

I have been shooting for a lifetime and reloading for 50 years and I have only seen one firearm blown up while firing a reload. It was a Star Starlite BKS, a 9mmL built on a .380 frame. The feed ramp on the barrel required undercutting for the longer cartridge to fit and left about half the 9mmL brass case unsupported in the chamber. Every case fired in this gun ballooned on the bottom until one case finally gave up and totaled the pistol.

I have found .22 rimfire ammo incredibly tough over the years. I have used old worn out .22 rifles that allowed the cases to swell, have examined guns with chambers that left part of the case exposed during firing and have fired .22 rounds through many things that were not intended to be guns.

If you are old enough to remember the old fashioned telescoping car radio antennas that were made from brass be aware that a .22 shell is a perfect fit in the largest of the tube sections, and 1/8" iron water pipe holds one perfectly too as well as 1/4" stainless steel automobile brake line. (just reference information that hopefully is never needed in that world of suspended legalities.)

Yes I have fired .22 rim fire through all those things, and lived to tell the tale.

And our component shortages over here have forced me to use many powders I never knew were available just a few years ago. I have been forced to experiment and improvise, using proprietary shotgun powders for reloading pistol and light rifle rounds, comparing burn rates and tracing charge volumes for comparing unknown powders to ones I am familiar with. Doing estimations and comparing pressure signs on fired cases has always been a standard action for me and I have spent the money for a chronograph which I never expected to own just a few years ago.

In a survival situation would I break down a 20 gauge shell, transfer the primer/powder/shot to a 12 gauge hull using newspaper for wadding and use it to feed my family or defend them???

In a single heartbeat I would!

Would I break down a .308 shell to rebuild one for my 30-06 or a .303 shell for my .308?

Yes, in the same instant.

Even with all this info floating around in my head I will probably never pursue reloading the Berdan primers. I keep standard boxer cases just to avoid that, however I do have a great deal of Russian military steel case ammo using that system.

Yes, I will save the cases. If you flatten them with a hammer, leaving the case mouth open, you can trim them with tin snips and make fantastic broad-heads from them! They fit a 5/16 arrow shaft very well.