Subsonic vs Supersonic 9mm FMJ for self-defense

[RadekSkylark]

Hello, everyone!

I'm about to buy myself a 9mm pistol for self-defense. I'm from Latvia (Europe) and we're not allowed to use any type of expanding bullets for self-defense (Geneva convention, probably), so I'll need to carry an FMJ round.

One of the brands readily available locally is Sellier & Bellot. They have 9 mm FMJ rounds either supersonic or subsonic. The main thing I have about carrying FMJ is overpenetration. For that reason, I carry wadcutters in my revolver (minimizes the problem as well as lower energy/recoil).

I don't understand a lot about ballistics, but to me it seems a good idea to carry subsonic 9 mm rounds, especially considering that the options from Sellier & Bellot have a flatter nose than the supersonic "round nose" FMJ. One of the subsonic is more like a semi-wadcutter, and the other is more like a round nose bullet, but with a flatter nose. Subsonic semi-wad cutter has 20% less energy than the usual subsonic FMJ. To me, it seems that it should also minimize the problem with overpenetration at least a bit.

If that is not the case and I should stick with supersonic for whatever reason it seems that the best bet is to go with the one that has the least amount of energy (again, looking at Sellier & Bellot its their 124gr, not 115gr FMJ round).

With regards to semi-wadcutters, do these usually work fine with pistols (I'll be buying G19 Gen 3 and USPc)?

Would you agree with my conclusions? Are there any other things I should take into account with regards to subsonic rounds and semi-wadcutters in pistols?

Thanks

 

[Ethan Verity]

What is the bullet weight on the subsonic rounds? I'm guessing 147gr?

If so, then overpenetration with FMJ would still be a problem, because of the higher sectional density of the round. A light 9mm subsonic not so much, but then it probably won't cycle the action reliably anyway.

I would go with the subsonic rounds since they are flat nose, that's probably your best option. I carry 147gr 9mm for defense, however they are JHP rounds (Federal HST).

Whatever you choose, be sure to run a few boxes through your gun first to confirm reliability.

 

[JTQ]

Speed allows the hollow point to open up, which slows the round and reduces penetration.

Sub-sonic rounds are typically designed for silencers.

For a personal defense round, especially with a relatively small/light bullet, speed is generally to your advantage.

Over-penetration is near the bottom of my concerns. I'm not LE, and chances of me shooting somebody is small, and shooting somebody, in a defensive situation, in a crowd is even smaller. Using the Kyle Rittenhouse ( https://en.wikipedia.org/wiki/Kenosha_unrest_shooting ) shooting as an example, he was marginally trained, he had a rifle, shot folks in a crowd, while under duress, and only shot those he intended to shoot. Nobody was struck by an over-penetrating round.

Edit to add: I overlooked "FMJ" - as mentioned above, in FMJ the heavier round would probably penetrate more due to greater mass and sectional density.

 

[JJFitch]

When choosing loads for self-defense practice ammo, I look at the manufacturers data for similar bullets. For example, if Winchester is showing 1050 fps for a 124 grain FMJ JRNFP bullet I would load a similar bullet close to that velocity. This is especially true for half jacketed or hollow point bullets. The manufacturers have done lots of testing to get the best performance from their bullets. Also the POA/POI would be close for fixed sights.

Note: As a retired LEO I'm using "duty" ammo in my self defense firearms!

"Lucky Gunner " has ballistic charts that show penetration and expansion data/photos for most common handgun cartridges and bullets

Smiles,

 

[RadekSkylark]

Thanks for the replies, guys. Just to say it once more - I'm talking ONLY about FMJ rounds (in Latvia expansive loads, either soft point, jacketed or usual hollow point or any other round that is designed to expand at impact is not allowed).

The particular S&B subsonic rounds are 140gr for semi-wadcutter (https://www.sellier-bellot.cz/en/pr...on/pistol-and-revolver-cartridges/detail/284/) and 150gr for the round nose (with the relatively flat nose - https://www.sellier-bellot.cz/en/pr...on/pistol-and-revolver-cartridges/detail/283/)

Please, teach me a thing or two (if possible) about terminal ballistics.
1) If, for example, we have two rounds with the same bullet weight and the same initial speed (thus same energy), the one with the higher ballistic coefficient (that is, the one which has worse "aerodynamic" probably because a "flatter" or in other way "bulkier" front end) will penetrate less than the one with a lower coefficient (thus, more aerodynamic shape)?
2) If, for example, we have two rounds with the same energy, but different bullet weights (which I presume influences their ballistic coefficient), but the same exact bullet shape (thus, the one which is lighter has higher velocity), then both should penetrate the same, shouldn't they (I presume the one that is heavier would be more stable in its trajectory if it would hit a hard object, but in an ideal GEL, they'd perform the same, wouldn't they)?
3) if, for example, we have two rounds, one with 100% relative energy, but the other with 80% energy, and this one is with a higher ballistic coefficient (thus, less "aerodynamic" shape), this one should penetrate less, shouldn't it?

Anyways, maybe all this even on such a "principal" basis is not as simple as I'm trying to make it just to figure out the "relative" performance between FMJ rounds.

Just to add, when I'm talking about over-penetration I'm not only concerned about my backstop, but also the amount of energy dumped into the target (I'm aware of the fact that with rifle rounds even with overpenetration the higher the velocity the more damage, but if I'm not mistaken the same does not apply to relatively low velocities of handgun rounds, correct me if I'm wrong, of course).

When looking at subsonic 9 mm rounds I'm not hoping that they'll eliminate the overpenetration problem, but hopefully will reduce it.

 

[Mycin]

Firstly, higher ballistic coefficient is MORE aerodynamic, not less. I've not given it much thought, but I suspect that a higher-BC bullet would penetrate more, everything else being equal (which it seldom is).

If I had to use non-expanding bullets for self-defense, I'd want it to have the flattest meplat (nose) possible. Handgun hunters have long found that flat nose bullets produce wound channels significantly larger than bullet diameter, whereas rounded nose profiles don't. I'd also want the bullet to be as light as possible -- the cavitation from flat nose bullets increases as velocity increases and a lighter bullet is generally less likely to over-penetrate.

Of the two S&B rounds you linked above, I'd definitely go with the 140gr "semi-wadcutter". It should penetrate less and also create a larger wound channel.

 

[Hartkopf]

Doesn't S&B make a soft point 9mm load? I would test those by shooting clear gel (or water jugs) and see if the point flattens/deforms any at all. If they do, and function reliably, I'd carry those. There might be other, better rounds but I've seen S&B sell something like a soft point.

 

[.455_Hunter]

Fiocchi and PPU both load a sub-sonic 9mm 158 gr FMJ. I sure would not feel unarmed with those for defensive purposes.

 

[RadekSkylark]

Firstly, higher ballistic coefficient is MORE aerodynamic, not less. I've not given it much thought, but I suspect that a higher-BC bullet would penetrate more, everything else being equal (which it seldom is).

If I had to use non-expanding bullets for self-defense, I'd want it to have the flattest meplat (nose) possible. Handgun hunters have long found that flat nose bullets produce wound channels significantly larger than bullet diameter, whereas rounded nose profiles don't. I'd also want the bullet to be as light as possible -- the cavitation from flat nose bullets increases as velocity increases and a lighter bullet is generally less likely to over-penetrate.

Of the two S&B rounds you linked above, I'd definitely go with the 140gr "semi-wadcutter". It should penetrate less and also create a larger wound channel.

Yeah, you're correct, a higher ballistic coefficient indeed means a higher capability of overcoming resistance (I edited it vice versa in my previous post for others that'll chime in).

Oh, so, with two identical, for example, semi-wadcutter bullets you'd prefer one that has a higher velocity (more energy) than the one with a lower (considering the same bullet weight, thus, lower energy), which you're saying would result in less overpenetration? Or would you make such a choice only if the energies would be the same (that is, lighter, the faster bullet would over-penetrate less than a slower, heavier bullet if the energy would be the same)?

Doesn't S&B make a soft point 9mm load? I would test those by shooting clear gel (or water jugs) and see if the point flattens/deforms any at all. If they do, and function reliably, I'd carry those. There might be other, better rounds but I've seen S&B sell something like a soft point.

S&B does make soft-point, but as I understand they also do expand, so I'm not allowed to carry such around. I cannot test them, cause we don't have a possibility to buy gelatin here locally to do our own tests.

 

[Mycin]

Oh, so, with two identical, for example, semi-wadcutter bullets you'd prefer one that has a higher velocity (more energy) than the one with a lower (considering the same bullet weight, thus, lower energy), which you're saying would result in less overpenetration? Or would you make such a choice only if the energies would be the same (that is, lighter, the faster bullet would over-penetrate less than a slower, heavier bullet if the energy would be the same)?

A lighter bullet will usually be faster and I'd prefer a faster bullet because, for a given meplat size, more velocity gives a larger wound channel.

If the velocities are the same, a lighter bullet will be less likely to over-penetrate and will also have less recoil, making follow-up shots quicker/easier.

All this goes against my normal inclination toward bigger, heavier bullets. My standard 9mm defensive load is a 147gr HST hollow-point -- expands big and drives deep. But for non-expanding 9mm defensive rounds, flat, light and fast makes the most sense.

Another idea is something loaded with the Lehigh Xtreme Penetrator bullet (https://lehighdefense.com/355-caliber-115-grain-xtreme-penetrator-lead-free-bullets.html) or the Black Hills HoneyBadger (http://www.black-hills.com/shop/honeybadger/9mm-luger-hb/). I don't know if anything like these are available to you there, but they're non-expanding and by all accounts make impressive wound channels.

 

[RadekSkylark]

@Mycin, thanks for explaining. Basically, for me, that means finding the bullet with the biggest meplat and then choosing the fastest one, basically, of if there are few options with the same meplat and velocity, choosing the lightest one. Considering this, it seems that using wadcutter in my revolver is probably the best thing I can do (or maybe semi-wadcutters with higher velocity would be even better)?

Unfortunately, the rounds you've mentioned (Lehigh and Black Hills) are not available here. To be honest, nothing besides usual FMJ rounds is available. Maybe if I'd be ready to buy sick quantity by myself I could get something ordered from the manufacturers represented locally (including Hornady, Federal, Magtech, Geco, Barnaul, S&B, CCI, Fiocchi).

 

[CapnMac]

Please, teach me a thing or two (if possible) about terminal ballistics.

Someday I hope to actually know anything about the topic.
I have to admit to relying upon video sources, like Lucky Gunner, and the like on You Tube for having the time and patience to compare and contrast different kinds of ammo.

Now, the "views" are mostly going to be of HP and similar "defensive" ammo, so, most reviewers will focus their attentions (and videos) there.

It's easy to get caught up in the details, the minutia, of ammunition. And, shot placement tends to be far more important than the "what with" of the shooting.

There's not that much different between a 115gr at 1150fps and a 130gr at 1040fps, not at under 30-50 yards' range. Flat point versus ogive FMJ probably more about how they feed than terminal effect.

US Emergency Room doctors tell us that, generally they can only tell "bigger" or "smaller" than about .38/9mm caliber from wounds (and that 5 of 6 GSW p/ts survive, if they make it to the ER).

So, were I in that situation, I'd use what fed best and most reliably in my chosen firearm.

Over-penetration is always a worry--all of the responsible shooting community will keep Rule 3 in mind as a reflex. And there's just not a lot of real-world data to rely upon, either.

 

[Mycin]

@Mycin, thanks for explaining. Basically, for me, that means finding the bullet with the biggest meplat and then choosing the fastest one, basically, of if there are few options with the same meplat and velocity, choosing the lightest one. Considering this, it seems that using wadcutter in my revolver is probably the best thing I can do (or maybe semi-wadcutters with higher velocity would be even better)?

Stay with your wadcutters. They have a much larger meplat than the semi-wadcutters. Faster is better for a given meplat size, but a bigger meplat is better still, in my opinion.

 

[jak67429]

First make sure the rounds cycle in your gun. Some guns will not cycle or feed the subsonic ammo.

 

[reddog81]

Try a couple different weights, bullet types, brands and get some experience handling your new gun while doing it.

Which ammo shoots most accurately in your gun?
Which ammo functions reliably?
Which ammo is easiest to control and allows for follow quick up shots?
Which ammo is priced most reasonably so that you can afford to practice with it as needed?
How many angels can dance on a pin head?

All more important considerations than which type of 9mm offers least risk of overpenetration.

 

[N555]

Can you get swagged soft lead bullet ammo there?

 

[9mmepiphany]

Thank you for the links to the bullets available to you. It really helps as most of us aren’t familiar with those offerings.First I’d like to say that S&B is a highly reputable company well known for making high quality ammo…they are a NATO ammunition provider.

Of the two bullets you have to choose from, I would go with the 140gr FN loading. That bullet design/profile is very similar to that proposed when the US armed forces adopted the 9x19mm round for their service weapon…ours was 124grs. That round demonstrated very good accuracy in several pistols. It also fed very reliably.

Generally speaking, heavier bullets will penetrate further than lighter bullets. However, it has been proven over time that shot placement is often the deciding factor in defensive shooting. If the round is reliable in your pistol, you should be fine with the FN bullet. I can’t imagine you’d encounter feeding issues with either the Glock or the H&K

 

[RadekSkylark]

Try a couple different weights, bullet types, brands and get some experience handling your new gun while doing it.

Which ammo shoots most accurately in your gun?
Which ammo functions reliably?
Which ammo is easiest to control and allows for follow quick up shots?
Which ammo is priced most reasonably so that you can afford to practice with it as needed?
How many angels can dance on a pin head?

All more important considerations than which type of 9mm offers least risk of overpenetration.

You're most probably right that the reliability, accuracy, recoil as well as price are much important overall factors than the possibility of bigger or smaller (but most likely still) overpenetration.

Can you get swagged soft lead bullet ammo there?

Nop, there are non available here.

Thank you for the links to the bullets available to you. It really helps as most of us aren’t familiar with those offerings.First I’d like to say that S&B is a highly reputable company well known for making high quality ammo…they are a NATO ammunition provider.

Of the two bullets you have to choose from, I would go with the 140gr FN loading. That bullet design/profile is very similar to that proposed when the US armed forces adopted the 9x19mm round for their service weapon…ours was 124grs. That round demonstrated very good accuracy in several pistols. It also fed very reliably.

Generally speaking, heavier bullets will penetrate further than lighter bullets. However, it has been proven over time that shot placement is often the deciding factor in defensive shooting. If the round is reliable in your pistol, you should be fine with the FN bullet. I can’t imagine you’d encounter feeding issues with either the Glock or the H&K

As for S&B I probably can get anything they offer, as this is one of the most sold brands here (few shops stack them).
Thanks for the input on the design for the 140gr subsonic round, very interesting information.

 

[C-grunt]

If those were my options I would go with the 140 for the wider meplat profile. It's not going to make much of a difference in the wound channel but it should create a slightly larger wound channel. In reality the difference might be more in theory than practice. I highly highly doubt the outcome of a defensive encounter will come down to the bullet profile of a FMJ round. That being said I dont see a downside of going with the flat nose profile. Actually that profile might do better at angled shots on bone where the more rounded profile may deflect off.

As far as overpenetration goes, both will do it handily. Any full power 9mm FMJ is going to have a good amount of penetration. In my experience 9mm ball ammo usually completely penetrates a person, easily.

 

[film495]

interesting question. I tend to carry 115 grain fmj in 9mm, but mostly just because I got a bunch of it cheap, and I know it works with no issues.

 

[TransAmConvert]

Maybe some members from New Jersey could comment, they're not allowed hollow points either.

The best thing 9mm has going is capacity. If it's me, I'm not worrying about which bullet but rather that I have a lot of them.

As I think about it, maybe FMJ is a good choice right now in Latvia. Never know if your assailant could have armor on. Stay safe.

 

[9mmepiphany]

Thanks for the input on the design for the 140gr subsonic round, very interesting information.

I’ve shot thousands of round of 9mm loaded with the RMR 125gr Matchwinners which share the same -profile as the 140gr bullet you’re considering.

It feeds very well through all my pistols and has outstanding accuracy. I’m driving them around 1050fps

 

[wcwhitey]

I like the look of the flat nose on the 140 grain bullet, sharp shoulders help with solid bullets. However, as suggested before try a box of each bullet. Most 9mm’s are designed for 124 or 115 NATO rounds and sights adjusted accordingly. See what functions and shoots to the sights the closest. Factor in recoil and the choose the best shooting bullet with the flattest least rounded nose profile. Hope this helps.

 

[trackskippy]

Given your choices, I wouldnt get too concerned what the bullet was and would just shoot focus on knowing what to shoot and being able to hit what you were shooting at, quickly and on demand.

People get way too wound up in what the bullet is supposed to do, and think it will make up for their lack of skills. Turn that around 180* and you'll do better with anything. If you cant quickly, accurately, and repetitively place your shots, the bullet isnt going to make a whole lot of difference.

That said, if you have the choice between FMJ and a true SWC, Id choose the SWC, as long as they function reliably in your gun. The SWC is the better choice for what you want it for, but reliability is more important than bullet choice.

 

[Ethan Verity]

As I think about it, maybe FMJ is a good choice right now in Latvia. Never know if your assailant could have armor on. Stay safe.

Wouldn't matter either way if they have armor on.