The .380ACP and 9mm guns from Bersa (also sold as the FireStorm by SGS - compact models) are a bit different.
The .380 being of lower operating pressure only requires a simple blowback action to safely shoot. The 9mm usually requires some type of delaying process before the slide opens up. (There are exceptions, of course, like the Hi Points which are also simple blowbacks for the 9mm as well as .40 SW and .45ACP. They achieve safe operation by stronger recoil springs and heavier slides.)
For the .380, the barrel is fixed to the frame and is immobile during recoil. Whereas the 9mm usually have some type of barrel/slide lockup that delays seperation of the two until pressures in the chamber reduce to a safe level at which point they come apart. Another exception are gas retard actions like the HK PSP/P7 where the pressure of the gas is actually used to keep the slide closed to the fixed barrel until pressures drop. For the Bersa/FireStorm 9mm, it is like any other linkless cam that the barrel follows.
Besides operation, the .380 andd 9mm Bersa/FS guns are different in many ways. The safety for the .380 is slide mounted and the 9mm frame mounted. Disassembly, due to the different operating processes, are different.
You can review the differences from their manuals at Bersa's and SGS's site,
http://www.bersa-sa.com.ar/bersa.asp
http://www.firestorm-sgs.com/
Personally, I've never tried a .380 Bersa, should have got and 85 before the high cap ban but let that slip. They have, from what I've read, generally good reviews. The only thing closest to the Bersa 9mm in terms of price and build quality is Ruger and Taurus for a little more in price. For even slightly more is the more renowned CZ75.