45 load spiting

[Aguila Blanca]

Originally Posted by Jeryray

Also I tried 4.3 g BE, was pretty good,once in a while a spat of soot would wind up on the glass on the red-dot.

Several years ago I was testing a new 1911 that came from the factory with a holographic sight on it. It was a 9mm and I wasn't loading for 9mm back then, so all I had was factory ammo. After about 100 rounds the sight was so black you could hardly see through it.

[Unclenick]

Originally Posted by Marco Califo

That is insight for lead bullets...

I think if you give it a moment's refection, you will see the minimum pressure that can deform a bullet is the limit you can expose it to and still expect to meet its accuracy potential, regardless of what it is made from.

The reason velocity is meaningless without additional information is revealed by considering barrel length. If you take a handgun bullet, plated or cast, that has been assigned a velocity limit of, say, 1200 fps, and load it to that number for your handgun, then fire it in a carbine rifle, it will not experience any more stress in the carbine than it did in the handgun because the peak pressures are the same. But it will exit the muzzle moving faster without any Ill effects it didn't display in the handgun.

[Marco Califo]

But if you fire plated bullets in the carbine and exceed the speed rating there is a possibility the plating and lead core will separate.
What I meant, in my quoted post, was that Berrys copper plated bullets resist blow-by and deformation better than bare lead. The copper plating is rather tough. And can be loaded to higher velocities than cast.
Hodgdon's reloading data center does list some 45 200 lead (not plated) up to 1100 fps (CFE Pistol).

[Unclenick]

I agree the plating is tougher than swaged lead or most cast bullets, allowing for the pressure to get higher without introducing a problem. But it is not as tough as jackets (though I don't think jacketed bullets are normally subjected to pressures high enough to cause their bases a problem).

As to velocity, assuming the pistol and the carbine have the same rifling pitch, forces won't do anything to the bullet structure inside the carbine that they don't do inside the handgun. Speed itself doesn't damage the bullet, forces do. Everything that happens to the bullet past the length of the pistol barrel is happening at dropping pressures and dropping resulting forces. Stripping, where it occurs, is at its worst when a bullet is subject to peak pressure because that is when the most force is applied to the bullet base resulting in the greatest linear and rotational acceleration. That peak occurs inside both the handgun and carbine barrels when the bullet is still near the throat, so it is no greater in the carbine.

The only thing speed itself does is cause the bullet to experience higher air pressure (resulting in drag force) on its nose when it leaves the muzzle blast sphere. It varies with BC, but is maybe on the order of 1 lb vs 1.5 lb or so. You can push on even a soft swaged bullet with your thumb harder than that without deforming it.