What is your definition of a +p load. Is it the max load in the manual or slightly above? Or based on pressure, velocity, or other?

quote:

Is it the max load in the manual or slightly above?

NO!

Your loading manual will (or should) identify these loads specifically as +P loads

They are higher pressure for firearms that can handle the higher pressure. The .38 Special is a good example as is the .257 Roberts.

You MUST know that your firearm is capable of handling the higher pressure loads.

Google SAAMI specs & you'll see a listing of their +P rated rounds. It's rated by pressures above what they deem std. There is no way to determine how much over pressure you are, if at all, by exceeding loading manaual data. It's why it's recommended to not exceed industry data.

+P loads are just that...+ Pressure! Loaded for better performance from a specific cartridge, but not so heavy that they will destroy a good-quality firearm, if used sparingly.

A good manual should give you accepted +P loads.

I don't need to feel like I have touched off a WMD, so I load what my brother in law terms "hot .38-mild magnum" loads in my .357 all the time. Probably close to what some of the old timers used in their 38-44 revolvers, with complete satisfaction. Accurate, & pleasant to shoot, and no slouch when it comes to "stopping power".

+P Loads do not exceed SAAMI spec. They bump right up to the edge, and conform to load spec for the specified caliber.

ANY gun chambered for the specified caliber will safely shoot +P loads. But if you shoot +P in cheap, or light weight, alloy guns the heavier loads tend to stretch frames and "shoot loose" the gun.

But ALL guns shoot loose eventually. That's basic mechanics. It's the best argument for buying quality guns and not opting for "light" guns in things you plan to shoot on a regular basis.