The Firing Line Forums - View Single Post - .38 special 200 grain bullet 1000-1200 ft per second

Wrangler5 · February 2, 2006, 06:49 PM

Since I have an energy calculator in a spreadsheet I decided to look at the comparative energies you'd be talking about. A 200g bullet at 1000fps has an energy of 444 foot pounds, while at 1200fps it would be 639 ft#. (Energy is a function of the square of velocity - a 20% increase in velocity brings a 40% increase in energy.)

Using the data from my Accurate powder data book, the hottest 38 Special +P load is a 158g XTP bullet at 900 fps, energy = 284 ft# and chamber pressure is 18,500 psi, the industry maximum for +P. A hot 357 Magnum load uses a 180g XTP @ 1196 fps, energy = 572 ft#, pressure = 27,000 psi (I'm extrapolating here, my book gives 38 data in psi and 357 data in CUP.) This is twice the energy of the hottest 38 Special +P, lands right in the middle of the energies you're looking at, but generates almost 50% more chamber pressure. (You can push this bullet even faster with other powders, but pressures go to the 33-34,000 psi range.)

There's a reason we can buy 357 magnum guns and ammunition - they're designed to take the energies a 357 mag round generates. I can't imagine wanting to run 357 Magnum pressures in 38 Special brass in a 38 Special chamber. Even if others may have gotten away with it.

February 2, 2006, 06:49 PM	#22
Wrangler5 Senior Member Join Date: September 18, 2005 Location: Missouri Posts: 326	Since I have an energy calculator in a spreadsheet I decided to look at the comparative energies you'd be talking about. A 200g bullet at 1000fps has an energy of 444 foot pounds, while at 1200fps it would be 639 ft#. (Energy is a function of the square of velocity - a 20% increase in velocity brings a 40% increase in energy.) Using the data from my Accurate powder data book, the hottest 38 Special +P load is a 158g XTP bullet at 900 fps, energy = 284 ft# and chamber pressure is 18,500 psi, the industry maximum for +P. A hot 357 Magnum load uses a 180g XTP @ 1196 fps, energy = 572 ft#, pressure = 27,000 psi (I'm extrapolating here, my book gives 38 data in psi and 357 data in CUP.) This is twice the energy of the hottest 38 Special +P, lands right in the middle of the energies you're looking at, but generates almost 50% more chamber pressure. (You can push this bullet even faster with other powders, but pressures go to the 33-34,000 psi range.) There's a reason we can buy 357 magnum guns and ammunition - they're designed to take the energies a 357 mag round generates. I can't imagine wanting to run 357 Magnum pressures in 38 Special brass in a 38 Special chamber. Even if others may have gotten away with it.