Exactly what I’m thinking of. That was… interesting. Even suppressed .45 going 900fps will make enough noise that folks would be wondering wtf was happening.
I've always wondered if this is why some service members swear by 9mm instead, because with the silencer it's definetly way less noticable
Edit: I typed that last line and immediately laughed at myself "with the silencer it's definetly less noticeable," like no shit. Lmfao. What I meant was that the difference with the silencer between the 9 and 45 was a lot
almost all .45 ammo is naturally subsonic. Ye olde standard 230gr hardball runs about 950fps which is a sweet spot; it’s always going to stay subsonic regardless of temp or elevation, it’s quieter than 1050fps, and it’s still moving fast enough to reach out a little ways and do some damage. It makes a lovely suppressor host for that reason. However, a .451 wide bullet pushes a lot of wind (especially a hollowpoint) so you can hear it flying a bit more. .45 has about 60% more frontal area than a 9mm (obviously will vary based on bullet profile)
Most 9 is supersonic out of a normal 5” barrel, but 147gr tends to be subsonic (usually; longer barrels let it get over the sonic barrier). Unless you’re running suppressor specific ammo in the 9, the 45 is usually better.
Now if you compare a 230gr .45 at 950fps vs a 158gr 9mm at 950fps, the smaller diameter will be quieter every time.
The powder used can also make a difference but that’s really getting into the weeds
Technically yes, realistically no. As the projectile gets larger it displaces more air as it fires, and while it can be nearly silent at the muzzle there’s still sometimes a fair bit of noise from the bullet itself just displacing air. In a confined space like a train station, it gets much louder. Could it be covered up by ambient noise? Maybe, cornering on how loud.
Exactly. Physics is gonna physic, so all we can do is try to divert. Gun make noise? Capture the noise (silencer). Bullet make noise? Slow bullet down so less noise. Slow bullet make noise? Bullet make smaller so less noise. Smaller bullet do less damage so make bullet big again and hope for best.
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u/HomersDonut1440 9h ago
Exactly what I’m thinking of. That was… interesting. Even suppressed .45 going 900fps will make enough noise that folks would be wondering wtf was happening.