Fmj vs subsonic fmj question

[AKarms]

So I’m not super knowledgeable on cans and ammo, I’m shooting 115 and 124 blazer brass fmj in my micro normally. I just got some s&b 150g subs. I don’t hear any difference through the can whatsoever. I did a test mag with 5 blazer then 5 s&w subs. Absolutely no difference in sound…. Thoughts ? I wasn’t expecting alot but when I say no difference I mean NO difference

And to be clear I’m not saying the subs are loud, it seems maybe the blazer is quiet ? Barrel length of micro not allowing 115 to go supersonic ?
I guess I was expecting subs to be quieter than they are in comparison

 

[navgunner]

They’re probably all subsonic out of that short barrel. The speed of sound is 1127 ft./s at standard atmosphere pressure and temperature.

CCI Blazer publishes their velocities for 9 mm at 1145 FPS for the 115 grain and 1090 FPS for the 124 grain.

Yeppers, I’m willing to bet money that if you chronograph your setup, you’ll see that everything you’re shooting a subsonic

 

[AKarms]

They’re probably all subsonic out of that short barrel. The speed of sound is 1127 ft./s at standard atmosphere pressure and temperature.

CCI Blazer publishes their velocities for 9 mm at 1145 FPS for the 115 grain and 1090 FPS for the 124 grain.

I’m willing to bet money that if you Krono you set up, you’ll see that everything you’re shooting a sub sonic

Makes sense. Thanks

 

[ericthered]

In the hot wether, your 115's could be subsonic in the right barrel. The main factor in my opinion for reducing sound level is less powder. Which in my opinion is the main factor in subs noise level. If i am reloading I worry bout those things. But dont sweat it when buying ammo.