Sub1100fps (or) Subsonic Ammo

[D K]

So, as a soon-to-be can owner, now’s time to start stocking up.

While a number of 147gr 9mm rounds indicate being subsonic, there are far greater options if shopping by rated speed.

Is it a safe bet that a round rated at 1000fps (which a number of them are) will perform as well as a subsonic-rated round (from a noise perspective)?

It would seem that a solid marketing tactic would be to label rounds under 1116fps as subsonic, but that doesn‘t appear to be the case.

 

[Creedmoor]

So, as a soon-to-be can owner, now’s time to start stocking up.

While a number of 147gr 9mm rounds indicate being subsonic, there are far greater options if shopping by rated speed.

Is it a safe bet that a round rated at 1000fps (which a number of them are) will perform as well as a subsonic-rated round (from a noise perspective)?

It would seem that a solid marketing tactic would be to label rounds under 1116fps as subsonic, but that doesn‘t appear to be the case.

I don't think you will find any standard 147 grain factory loads that aren't subsonic.
Its not printed on the box, because I would bet most buyers don't know the difference.
Maybe Andrew, will chime in.

 

[gmcttr]

Most sub ammo will go supersonic in my 8.3" barreled AR9. The exception to this Federal 150gr Systech. It stays sub sonic in the longer barrel

 

[edwea]

You will find that there are bullet weights that are known to be subsonic within certain cartridge offerings. For example, no one buys 115 gn 9mm expecting subsonic performance but everyone buys 147 (and heavier) 9mm expecting subs. With 300 blackout, 110,125,147 are all supers while 200 gn and above are assumed to be subs.

 

[AllenM]

The best results I have seen in sub sonic 9mm are with 165gr rounds. Almost dead silent with my liberty can and very quiet in a Silencerco 9K

 

[edwea]

The best results I have seen in sub sonic 9mm are with 165gr rounds. Almost dead silent with my liberty can and very quiet in a Silencerco 9K

Do you cast these yourself or buy?

 

[Aszerigan]

Do you cast these yourself or buy?

9mm 165 RN

9mm 165 RN

www.xtremebullets.com

 

[AllenM]

You can buy loaded ammo in 165, I load with Extreme plated bullets

 

[AllenM]

9mm 165 RN

9mm 165 RN

www.xtremebullets.com

I am burning through some excess VV powder and get very good results

 

[Aszerigan]

Is it a safe bet that a round rated at 1000fps (which a number of them are) will perform as well as a subsonic-rated round (from a noise perspective)?

It would seem that a solid marketing tactic would be to label rounds under 1116fps as subsonic, but that doesn‘t appear to be the case.

To the OP's question - manufacturers use the word "subsonic" as a marketing tool. Winchester white box 45acp is a naturally subsonic round, but they also sell "Super Suppressed" black box 45acp with a cool logo. It costs a good bit more. Why? Because most people (OP excluded, he understands the laws of physics) don't know that the 45 is subsonic anyway. Note: I've seen improperly loaded supersonic 45acp with a 230gn ball. It does destroy the host firearm.

To further complicate things - subsonic at sea level isn't the same loading data as subsonic at 4000 ft. Subsonic at 90 degrees F often isn't the same load as 20 degrees F. (There are temperature stable powders, but that's a can of worms for another thread.) Also, the speed of sound is different at higher elevation than it is at sea level. When the air is thinner, there is less resistance (i.e. cold, higher elevation) so rounds on the cusp of the sound barrier will break that magic number.

Why don't manufacturers call 9mm 147gn subsonic ammo? My guess is that they can repackage the same ammo, put it in a much cooler and "tactical" box and sell it to unsuspecting people for more money.

The thoughtful answer is that they never know the barometric conditions / elevation of the shooter using their products, and that can change the performance of a round. The real world answer is people shell out a lot more money for ammo in cool boxes.

 

[Aszerigan]

And one more note - barrel length can affect subsonic / supersonic performance too. A round that is subsonic from a 8" barrel might be 1100fps+ from a 16" barrel. Back to the point that the manufacturer never knows how the end user will use the ammo.

I'm guessing the "super suppressed tactical evil black box silver writing mega suppressor awesome costs more ammo (did we mention it's for suppressors") ammo might be downloaded slightly to guarantee it's subsonic from a longer barrel. That again assumes ammo manufacturers aren't money grabbers from the tacticool crowd, and we all know that IS the case.

 

[Aszerigan]

Most sub ammo will go supersonic in my 8.3" barreled AR9. The exception to this Federal 150gr Systech. It stays sub sonic in the longer barrel

Another argument for loading your own. You can make almost anything subsonic if you want to.

 

[Aszerigan]

For example, no one buys 115 gn 9mm expecting subsonic performance

 

[edwea]

Nearly anything is possible for the handloader but I gathered the op was referring to factory loads.

 

[STFU]

...<SNIP>... The real world answer is people shell out a lot more money for ammo in cool boxes.

^^^ Spot on! ^^^

 

[way2good4u95]

Barrel length is the big thing. With those fps ratings, have to check length of barrel they shoot from. I've had good luck with Freedom Munitions ammo despite what some people think. I can buy their 147gr 9mm and it's subsonic through my CZ Scorpion. But if I had a 16"+ barrel 9mm rifle, I'd probably opt for their "subsonic load" due to it being rated at an even lower fps and better chance of it staying in subsonic fps ranges through the longer barrel even though it costs much more.

 

[BigNyaKelly]

So, as a soon-to-be can owner, now’s time to start stocking up.

While a number of 147gr 9mm rounds indicate being subsonic, there are far greater options if shopping by rated speed.

Is it a safe bet that a round rated at 1000fps (which a number of them are) will perform as well as a subsonic-rated round (from a noise perspective)?

It would seem that a solid marketing tactic would be to label rounds under 1116fps as subsonic, but that doesn‘t appear to be the case.

Yeah it's always worth mentioning that the subsonics tend not to take into consideration PCCs with long barrels! - I have a 16 inch AR-9 that basically turns anything into supers.