Subsonic 9mm question

[mofo1111]

Lighter bullets traveling faster produce more muzzle energy than heavier bullets going slower. It's just math. Muzzle energy=velocity x velocity x mass. Since velocity is squared, it has a higher impact on muzzle energy.

Heavier bullets "seem" to soft softer. PCC shooters may tend to like heavier bullets, like 147 grain bullets.

Some PCC shooters like to stay subsonic from the muzzle. That way the bullet does not get disrupted by passing through trans-sonic velocity. If you never go supersonic, the bullet never passes through trans-sonic velocity. This changes with different parameters, like temperature, humidity, altitude, etc. Let's say you are a PCC shooter and you have a 100 yard shot. If the bullet leaves the muzzle at super sonic speeds, but at 50 yards starts to go sub sonic, your once super accurate hand load may suffer past 50 yards.

Try using shooterscalculator.com and use the Ballistic Trajectory Calculator. It will create a chart and when a super sonic bullet will transition to sub-sonic and at what yardage(if you inout the correct parameters). You can select the range, and the increments of measurement.

If I shoot a PCC gun, I prefer a slower bullet. It tends to malfunction less with a heavier bullet vs a 115 bullet at same power factor, if the power factor is relatively low. This is just MY personal experience.

If it is a self defense cartridge, then I prefer a lighter, FAST bullet. I don't see myself shooting through car doors and such, in a self defense scenario.

[Sailormilan2]

It used to be the "mantra" that one should have at least 1000fps, at the target, for hollow points to reliably expand. The 147 gr doesn't even start out at that. It's actually not much better than the old "police" 38 Special load that had a bad reputation for being a "man stopper".
After the FBI Miami fiasco, and the "failure" of the Silvertips they were using, the FBI, and then many others, went to a heavier bullet. My Department did as they wanted "penetration". I was not impressed. Two homicide detectives from back East, Evens and Marshall, had done studies with regarding to how well different calibers did in shootings. They felt that the 147 gr 9mm would be less effective in "incapacitation" than the standard 9mm loads. IIRC, and it's been a really long time since I read the article, they came up with a figure of 10% less effective than standard 9mm loads.
IF I were to carry a 9mm for SD, my preference would be 124 gr JHP, then the 115 gr. I would use the 147 gr only if I couldn't find anything else.

[p7m8jg]

Standard 147's usually have less recoil or perceived less recoil due to the longer dwell time vs a faster and lighter round. More of a push than a snap.

Make sure it can cycle your handgun or PCC unless you're running a suppressor.

Maybe that's why I always liked shooting and seemed more accurate with 147 gr JHP subsonic ammo. Or so I thought.

[BrokerB]

Such a dam shame no suppressors for indoor use in Kalifornia

[deckhandmike]

Shoot what your gun runs well. You’re overthinking this.

[rodralig]

Shoot what your gun runs well. You?re overthinking this.

@deckhandmike has a point!


Just train with what you have... Many people can't shoot, regardless of whatever they have; and that includes ammo. 115gr VS 147gr...? Recoil...? It's a 9!!!



_

[walmart_ar15]

Lighter bullets traveling faster produce more muzzle energy than heavier bullets going slower. It's just math. Muzzle energy=velocity x velocity x mass. Since velocity is squared, it has a higher impact on muzzle energy.

Thus, since lighter bullet tends to lose velocity quicker than heavier bullet, impact KE will be lower at distances.

There is always a compromise. So really boils down to the application. Using a PCC would suggest your expected engagement to be > 25 yards.

Attached are data from the web. Basically, showing heavier bullets provide more impact at distances and better with longer barrels.

What's interesting is that at certain distances > 25 but less than 100. There will be a distance that performance will equal between the weights. So again, boils down to the application. What is your expected engagement distance?

[OlderThanDirt]

Several of my handguns like +P ammo with light bullets. My Shield performs best using a NOVX 9mm 65 GR/1,800 FPS/468 FT-LBS. For my PCCs, 9mm +P+ Winchester Ranger T-Series 127gr JHP works well.

In the end, any ammo you can get will suffice. Even crap ammo can kill if you need to defend yourself.

[sigstroker]

It used to be the "mantra" that one should have at least 1000fps, at the target, for hollow points to reliably expand. The 147 gr doesn't even start out at that. It's actually not much better than the old "police" 38 Special load that had a bad reputation for being a "man stopper".
After the FBI Miami fiasco, and the "failure" of the Silvertips they were using, the FBI, and then many others, went to a heavier bullet. My Department did as they wanted "penetration". I was not impressed. Two homicide detectives from back East, Evens and Marshall, had done studies with regarding to how well different calibers did in shootings. They felt that the 147 gr 9mm would be less effective in "incapacitation" than the standard 9mm loads. IIRC, and it's been a really long time since I read the article, they came up with a figure of 10% less effective than standard 9mm loads.
IF I were to carry a 9mm for SD, my preference would be 124 gr JHP, then the 115 gr. I would use the 147 gr only if I couldn't find anything else.

I believe in Marshall/Sanow's stats, 115 gr (Federal 9BPLE) which is +P or +P+ was the best 9mm. That could also be because 124 gr is not used as much.

[sigstroker]

Maybe that's why I always liked shooting and seemed more accurate with 147 gr JHP subsonic ammo. Or so I thought.

Note that Federal's "official ammo of the USPSA" 9mm Action Pistol is 150 grains.



They used to have a 160 gr load that was their "PCC" load, iirc.

[audiophil2]

I've been doing more reading on what type of ammo to use for carry and for a PCC.

I have tons of 115gr 9mm because it's cheap. But now, I see that many people prefer shooting 124gr and 147gr. Any reason why?

I have Hornady 115gr Critical Defense as my current carry, but I've been wondering if switching it to a subsonic 147gr round would possibly be better for carry and for the PCC.

The idea of firing a round that is subsonic "sounds" more pleasant for the ears, of course I'd rather lose my hearing than die due to an underperforming round.

Thoughts?

Seeing that we can't have suppressors in this state for home use, nor is it practical for carry, I figured saving 20 decibels would make a big difference.

I've always gone against the recommendation. My carry guns use the same FMJ I use to hobby shoot. Simply because my personal gun range has targets out to 150 yards so I shoot pistols out to that distance. If I use different ammo for practice vs carry I have to remember many more dope graphs. Plus I don't want to waste the money making sure expensive JHP cycles perfectly. I know which higher end FMJ works and I can dump a carry mag that might have month old ammo in it and just add in fresh. I doubt many guys cycle through a lot of JHP. I've seen customers with years old ammo that has gone through years of temperature and humidity cycles.

For carry I prefer 115gr quality made FMJ. It is faster and lighter so easier to carry 20+ rounds and shoots flatter. Fiocchi, Sig, Geco, Magtech. No WWB, Remington, or Federal.

I like the heavier bullets for suppressors and usually run Fiocchi 158gr 9mm. It is relatively cheap and only a little louder than my 165gr 9mm ammo. Out of a suppressor in the right gun like a SIG P226 or HK it is exceptionally quiet. Without a suppressor you deal with the muzzle noise of the gasses escaping. I know a few friends that have forward blast devices that drastically cut that noise down. Pretty much a reverse comp. The supersonic crack is further away from the gun and not really painful to hear even in 223 when suppressed.

There is a lot of hot 147gr ammo so it is not all subsonic. Federal is too hot to be subsonic in my experience. (On the opposite end, Federal subsonic 22lr is so weak it just drops like a rock at 100 yards. Gemtech subsonic .22lr is my favorite 22lr ammo.) It is a low quality brand so I don't use it. The red and blue tipped stuff they have is better but overpriced. I prefer Fiocchi, Geco, and Magtech. None is bulk. Just 50 round boxes. Bulk ammo goes back to my 150yard target issues. All bulk has inconsistent powder charges so while you will get good groupings at typical gun range 7-15 yards it is junk past 20 yards. Not an issue in self defense of a human but I have had to shoot dogs in the desert and 20+ yard accuracy is important on an already smaller target area. I carry 20+ in the desert just for dogs. Around town I just have 6.

[BucDan]

I really appreciate the input and discussion guys!

Nothing wrong with an open discussion. I just found it interesting that some folks just preferred heavier.

I know the deal with heavier rounds and distance, less wind drift etc. And I know lighter bullets fly faster, etc. But then again these pistol differences are likely within 25 yards, so I'd think not much of a difference in the end.

[mooster]

I switched to 147mm primarily because of logistics. I use 9mm M&Ps and have a suppressed, 9mm SBR that uses the Stern M&P/P320 adapter. The SBR is the very fun with subsonics. Rather than juggle/track M&P mags with 115 and 147gr, I just standardized on the latter.

[sigstroker]

I bought a mother buttload of 124's because it's hard to find 147's, and when you do find them, they're expensive. There are lots of 124 loads at or under 1100 fps.

[plumbum]

I used to shoot a bunch of 147 LRN 9mm thru my Hi-Point 995 and it shot great with them; a different impulse than the 115 fmj. Did have a small stash of 147 +P gold dots that were excellent and I'd certainly load up on an equivalent if I were setting up a PCC.