Corrosive Ammo

:madsmile::banghead::surrender:I stand properly chastised

Just adding, re. Berdan Primers;

The .250" one for the "classic" Brit / Commonwealth .303 case is the RWS 6000. Beware age cracking and mercuric "degradation" in these cases. One reload is good, Two or more is a miracle. Good for "bush ammo". The post-war FN 303 with the smaller Berdan (.217") is good for quite a bit of use, especially if you occasionally anneal and trim. I lost many more in the weeds than ever failed structurally.

If you are using OLD Brit or European big-bore metallics, or several of the European military cases, the .256" RWS 6504 is the go. Bizarrely, some of the steel-cased Russian? 5.56 x 45 "export" ammo also used this size.

Beware of the shallow-cupped version, number unknown. These are meant for reloading European-style SHOTGUN cases ONLY, and will probably not like the back-pressure from a full-house 7.62 x 54R load. I picked up a couple of packets (CBC) quite a while ago. "Trade goods" only, now.

It has been at least seventy years since a lot of the "old ones" were originally made. Unless you have barrels of that stuff, MODERN, Boxer brass and primers is the way to fly. MAGNUM primers, which have an "enhanced brissance" to ignite large quantities of slow-burning propellant, may be useful in "bigger" cases.

An old bloke at a clay club I used to shoot at would occasionally bring along his old, black powder 8 bore fowling piece. He used to put a tiny bit of smokeless powder in each cartridge so that it would shoot cleaner. He never claimed it would stop the corrosive salts, but he said it reduced them to a level where he could leave it longer before cleaning it.
I once saw a nice shiny new Beretta 92 barrel that had been destroyed by shooting a mag full of corrosive Eastern bloc 9mm ammo. It had been left a week before cleaning, and it was "toast".

I have heard this before.. to be honest I am wary about mixing powder types at the best of times, and unless I had a pressure test barrel, would stay well away from these practices. Interestingly this is the direct opposite of normal practice, where GP is used in large nitro cartridges to ensure good and even ignition. Typically the primer magazine down the centre of a Quick Fire case is filled with gunpowder and bag charges have gunpowder filled pads on the ends to pick up the flash from the tube.. The US 175mm Howitzer had a chamber around a meter long and the bag charges had a polythene tube filled with gunpowder running down the centre to ensure all the powder got lit. Much of this is to do with the US obsession with using single base, granular powder whereas "proper" people used Cordite!

...but to reiterate, it is the primer that caused most of the problems with corrosion, not the main propellent. Proper gunpowder residue is not that corrosive, and a good squirt of any water displacing fluid such as WD40 will keep the rust fairy away for a few days.. That said, some of the GP substitutes such as Pyrodex contain potassium perchlorate which does produce corrosive chlorine compounds and needs the hot water and washing soda treatment PDQ after firing..