sti spartan 40 cal conversion

[ironman5669]

I have an sti spartan in 9mm and would like to convert it to 40 what would I need to do?

[Cy Soto]

I have an sti spartan in 9mm and would like to convert it to 40 what would I need to do?

You probably will need a new slide and barrel since the 9mm breach face is slightly smaller than the .40S&W.

If this is the case, it might be cheaper to purchase a whole new pistol.

[Whitefish]

I stand corrected on this if I am wrong, but I believe the 9mm Spartan is an unsupported 9mm barrel and not the common fully supported Wilson/Nowlin cut used on the STI 40 cal competition guns like the Trojan, etc.. You would not want to shoot a regular diet of 40 cal loaded to major through an unsupported barrel. We learned that the hard way back in the early days of using 40 in USPSA. Ask me how I know.

So . . . you would also want to have the frame cut for a new fully supported barrel made for a Wilson/Nowlin or Clark Para cut. As Cy indicated, a new slide would be necessary in addition to the barrel. By the time you add up all the parts and fitting, you would almost certainly be further ahead to look at a gun already made specifically for shooting 40 at major power levels, like the STI Trojan or one of the Springfields. Once all this work is done, your 9mm top-end would no longer work on the lower and you could not switch back.

[sfinney]

9mm slides can very easily have their breach face opened up slightly to 40 size. Just have to find a gunsmith willing to do it. At that point you would need a .40 barrel, and as pointed out most .40 barrels are ramped, so you would need to get your frame cut for a ramped barrel, fit the barrel, and get some .40 mags. That should about cover it.

[STIGUY]

Know anyone who can or will open the breechface to accept .40 cal? Just wondering.....

[twodownzero]

By the time you add up all the parts and fitting, you would almost certainly be further ahead to look at a gun already made specifically for shooting 40 at major power levels, like the STI Trojan or one of the Springfields. Once all this work is done, your 9mm top-end would no longer work on the lower and you could not switch back.

Except that the Springfields and Kimbers are no longer available in .40, so you'd be in the same boat, unless you wanted a Spartan.