Are the 32 S&W and the Colt 32 the same round. I have an old Marlin .32 rimfire with the center fire firing pin. The gun came with both firing pins when manufactured abut 100 years ago. The Colt round shoots well in this old gun. Anybody have this experience?

NO! The .32 S&W and the .32 Colt NP are the same. Larry

Which Smith & Wesson and which Colt? The 32 S&W is NOT the same as the 32 Short Colt but the 32 S&W Long is the same as the 32 Colt New Police. Then there’s the Colt 32 And Colt 32 Long to consideralso.

Cartridges of the World, 16th Edition, page 185, 32 Long (Center Fire): “...the Marlin Models of 1891 and 1892.....The 32 S&W Long or 32 Long Colt will work in most old rifles in this chambering.”

As Roy Jinks says - I hope this helps.

Despite what "Cartridges of the World" says, the 32 S&W long and short will not come close to chambering in my particular Model 92. I use the outside lubricated 32 Short Colt or the inside lubed, hollow based, 32 Long Colt. I reload the Short Colt without resizing, using an 82 grain heeled bullet.

The 32Colt and the 32 S&W orig used the same bullet dia.
However, the 32 Colt was loaded with a heeled style bullet.
The 32 S&W is loaded with an inside (the case) lubed bullet.

That difference in bullet style made for the Colt round use a caseing with the same dia as the bullet itself.
The heel of the bullet being the inside dia of the case and the way it is held in the case. Just like a .22rf round.

So the 32 Colt round brass case is smaller in dia than the 32 S&W round using it's more common inside lubed bullet.

The 32 S&W round should not chamber in the early Marlin lever actions made with the two sided firing pin for 32 Rf or CF . These are chambered for 32 Colt using the smaller dia brass case.

To further muddy the water, the 32 Colt round was later loaded with an inside lubed bullet as well.
The case was not changed in any way.
So the bullet was reduced in dia to that of the heel of the orig heeled bullet round. The new inside dia lubed bullet 32Colt round now has a bullet dia of approx .291/293.
You can see a problem already shooting that throug a .312/.314 bbl.
A short hollow base in the bullet was added with the idea that the base would upset upon firing to fill the bore dia of the bbl and provide a sealed bore.

Some of the early 'Boys Rifles' that you may find in 32RF caliber are also factory made to be convertible to 32CF. By using a second link pin attachment hole to vary the breechblock placement, the firing pin can strike either CF or RF.
Again in those rifles the 32CF round that interchanges with the 32RF is the 32Colt round,,not the32S&W round with it's larger dia case.

(Many are gunsmithed by simply rechambering the smaller dia 32Colt chamber so they do infact accept the 32S&W round.
The conversion a simple thing to do on a single shot mechanism.
The use of 32RF is usually not important due to it's cost and rarity of quality ammo.)

This entire healed bullet transition to an undersized hollow based inside lubed bullet in the same case
also occured in the 41Colt rounds history of mfg as well.

The 'New Police' tags on Colt 32 and Colt38 pistol ammo were/are Colts way of marketing 32 S&W Long and 38 S&W w/o using the 'S&W' name.
32Colt New Police is a flat tip bullet edition of 32 S&W Long
38 Colt New Police is a flat tip bullet edition of 38 S&W.