I'm glad this thread came up again. "+P" ammunition can be successfully used in Smith & Wesson M&P revolvers made before the assignment of the model numeral "10" in 1958.

For how long...

no one knows.


How they could fail?

Let us count the ways.


I recently dusted off the chronograph to revisit a fairly extensive selection of .38 Special ammunition, both factory loads and handloads in 38 Special revolvers in each of five different barrel lengths I have on hand. I also tested some Buffalo Bore +P 158 grain ammunition (really amazing stuff, Buffalo Bore) and some SuperVel but may post the results over in the ammo section.

Here's some data for the revolver with the 5-inch barrel.


Handload: 158 grain round nose lead /3.8 grains Bullseye

MV 804 fps
ME 227 ft./lbs.
ES 51
SD 20

Independence 130 grain FMJ round nose

MV 888 fps
ME 228 ft./lbs.
ES 32
SD 9

Remington 148 grain hollow based wadcutter

MV 727 fps
ME 174 ft./lbs.
ES 20
SD 7

Winchester +P 158 grain lead SWC-HP (in gray box)

MV 922 fps
ME 298 ft./lbs.
ES 69
SC 26

Winchester +P 158 grain lead SWC-HP (in older white box)

MV 949 fps
ME 316 ft./lbs
ES 72
SD 32

Remington +P 158 grain lead SWC

MV 964 FPS
ME 326 ft./lbs.
ES 72
SD 32

Sellier & Bellot 158 grain FMJ flat point

MV 778 fps
ME 212 ft./lbs.
ES 36
SD 13


This 5-inch M&P was made before 1958. With a serial number of 502XX it was made long before that time in about 1904. Its finish has seen better days. In fact, it could be charitably described as ugly. There is little investment tied up in it and it has no value. Its outstanding mechanical condition and clean bore is positively antithetical to its surface condition. It has languished in the bottom of the Smith & Wesson collection for some time.

I've been threatening to put the old M&P to the test for some time but wanted to chronograph the results. I don't have a lot of common sense but did limit the test to only lead bullet loads. The old revolver was also not tested with Buffalo Bore.

It appears to have come through the tests with flying colors and is none the worse for the wear. It fired a total of 30 rounds of +P 158 grain ammunition. Of course the very next round could have opened up the cylinder but I suspect it wouldn't have. Most +P ammunition is a tempest in a tea pot, Buffalo Bore and SuperVel not included. A small benefit is gained by use of +P, especially in the heavier bullet weights, but it is no terror.

Primers appeared normal and extraction was effortless. Of the entire test conducted that afternoon, only the SuperVel exhibited any flattening of primers. This wasn't bad but did occur to some extent in all of the revolvers.


Of the +P lineup tested, only the gray and white Winchester 158 grain loads and the Remington 158 grain loads were tested. All others were kept out of the old M&Ps cylinder.