Tom painted the ends of several springs to identify them during the testing phase. Once testing was complete and the units started shipping, Tom only used one spring, the "orange" spring. The springs were no longer painted after that.
Every spring that has shipped is the "orange" spring.
With the A bolt, you’re absolutely correct.
From the beginning, recoil springs for every M–11/9mm W bolt ever produced used the “silver” springs sourced from MPA. shortly after the first 100 bolts sold, I had just over 400 recoil springs custom wound, but they didn’t work correctly with the M-11/9 W bolt and no bolts were ever shipped with this spring. Wonder springs... I wondered what I was going to do with a box full of them.
Perseverance and a little luck led me to the “orange springs’ and initially I sold them as an optional Super Slow, (SS) spring for use in the M-11/9 W bolt. During development of the A bolt, the “orange spring” was used and proved to be very capable performers. Consequently, every A bolt ever produced, no matter the configuration, has shipped with this spring. This is not an OEM style recoil spring and while it may be possible to use with an OEM Cobray style bolt, I would recommend against it for this application. I’d imagine the recoil impulse to the rear of the receiver would be quite harsh and possibly compromise the rear receiver welds.
A couple of forum members have stated they’ve been able to get the A bolt to run reliably with .380 ammo in the large magwell M11-A1 using the wonder spring. I have not tested this combination and don’t ship assembled A bolts or support this configuration’s use. I simply don’t have enough first hand data about the purported reliability to ship these without my own testing. I will offer the spring independently, but you’re 100% on your own.
Only later generation A bolts will run reliably with .380 ammo or are 100% reliable with an M-11/9.
Generations are designated by the font size/type.
I don’t count total coils, never have.
Most of the information being requested is already posted here in the forums or on the Vegas SMG FaceBook page including ROF numbers.
Actual sellers of used products should be the ones answering questions about their goods.