40S&W to 357Sig conversion: safe both ways?

[Green Rabbit]

I recently bought a 357sig barrel for my HK P2000SK, originally made in 40S&W.
Was about going to the range with it, but a friend of mine told me that 357sig has higher pressure, so such conversion may be not safe

I found that many 357 guns are coming with an extra 40 barrel, while the opposite is not that common

Is the 40->357 conversion safe? any other parts (but the barrel) may need to be upgraded?

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[cyclesarge]

Any gun that is sold in both calibers should be good to go. I just picked up a .357 P239 and am thinking going the other way. I think you may run into problems with going .357 conversion in a polymer frame .40 that was never designed for .357.

 

[Green Rabbit]

Well, that gun does exist for both calibers. The 357 barrel is original one, not aftermarket

Does 357 have significantly more recoil than 40, which makes it needed different frame?

While the pressure is higher, the bullet is also lighter - so I would be surprised if the slide gets much more backward momentum than with .40S&W round

 

[SDR]

Read this...

http://www.recguns.com/Sources/IIIC2g12.html