Either one will do the job, or fail miserably depending on the ability of the end user. The more important factors are which gun fits with your needs, abilities and lifestyle: revolver or semi-auto, large, medium or small? Answer those questions, only then worry about matters that are fairly inconsequential.

I feel sorry for the OP. A simple question and the answers have morphed into advance ballistics theory...

He did ask for thoughts?????

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NRA Cert. Inst. IDPA CSO

I won't volunteer to stand in front of .38, 9mm or even .22 short.

I doubt an assailant is ever going to say, "Ha! You hit me square in the chest. However, your projectile didn't expand and my vitals didn't experience enough energy dump to affect them. so I am undeterred in my will fight."

Over penetration is a non-issue IMO. Most shots will probably miss. If you're concerned about behind the target, probably shouldn't shoot at all.

RC, Mary Ann, Toyota!

I wanted to find out the answer, so I went to the Lucy Gunner site.

38 Special c/o 4.2" Ruger GP100
Top 125gr is the Reminton Gold Saber +P at 989fps.... ME271.

9mm c/o 3.5" M&P C9 with a Standard 9mm loading
Hornady 124gr XTP had a average speed of 1097fps.... ME331.

Is a 38 +P better than a standard 9mm with the same weight bullet?

A lot goes into these types xxx vs yyy threads.

Barrel length is huge as is bullet weight. The big ammo mfg's ammo is anemic at best. I know Ed has done extensive testing over the last couple of years that I followed on this website with the 38spl loads and now the 9mm.

At the end of the day IMHO:
short bbl's (3" or less) & light bullets ='s 9mm
short bbl's (3" or less) & heavy bullets ='s 38spl
4"/5" bbl's & light bullets ='s 9mm
4"/5" bbl's & heavy bullets ='s 38spl
6" & longer bbl's ='s the playing field starts to level with the edge going to the 9mm with lighter bullets
10" bbl's ='s doesn't matter with lighter bullets and anything over 147gr the 38spl really shines.

I have short bbl's 9mm's and use 124gr bullets
I have short bbl'd 38spl's and use 158gr/170gr bullets

I've done a little reloading/testing with both calibers over the decades. Bought my 1st chronograph in 1990, started casting bullets in 1985 & swaging bullets in 1990.

Started reloading the 38spl/357's in 1985. Since then I've tested bullets weighing 90gr to 200gr (lead & jacketed) in 1 7/8", 2, 21/2", 3", 4", 6", 8", 10" bbl's. I have no idea how many different powders I've used/tested, 20+ is being conservative.

Started reloading the 9mm in 1991/1992??? We would re-fit our 1911 38super race guns with 6" bbl'd 9mm bbl's. We used the extra length (38super 5"/9mm 6") of the bbl to get more speed out of the 158gr bullets we were using in the 9mm back then. Since then I've tested bullets weighing 90gr to 158gr in 3.2", 4", 5", 6", 10" bbl's with the same 20+ powders.

This doesn't make me an expert by any means. I'm just saying I've done a little testing in a bunch of different firearms/bullets/powders for over 25+ years. What little I've learned I listed above.

The primary advantage of the 9mm is not so much the ammo but the gun that shoots it. Faster reloads. Less recoil. Easier to shoot.

If I was a cop on the street, even as loyal as I am to the .38 Special revolver, there's NO WAY I would carry one instead of a 9mm semi-automatic.

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Centennial Every Day

Well, I have thought of this question, as basic as the OP question that is. Not the physics and calculations and all that stuff others have put on here, lol. I liked reading it though, some good info!!!

My personal feeling, is that the 9mm and 38 spl CAN be the same, and it seems that depending on manufacturer and bullet used..... they basically are.... just like I can make a 10mm do what a 40 sw does, or make a 454 Cassull do what a 45 acp does. But..... and to me it's a big but... the platforms are different, and so is the technology, imho.

When 9mm became the wonder gun (glock. High cap pistols, etc) technology and marketing took over, hence alot of R&D. The 38 spl hasn't gotten that kind of attention in many years. BUT, its shot out of a revolver,so the platform lends itself to much more versatility, from cat sneeze loads to wopping 170 grain bullets. 9mm, wont cycle action on cat sneeze and hasnt the space for 170 or higher bullets. So I think if you want versatility to shoot effectively, the 38 spl wins. If you want to stick to 125 grain and 147 subs for suppression, go 9mm, and learn those effectively. I've always thought it ridiculous that sub 9mm isnt that common, especially with suppressors being popular. It's kind of like rifles. Auto vs bolt. Want heavy hitter? Like 300 Win Mag. 338 Lapua? Go bolt, not semi auto. Same principal, unless money is no concern....

In the end, doesnt quite matter with self defense, both are proven loads, both would suck to be shot by, etc. My EDC is a SIG p238, pretty common, but I was jonesing for a 938 (380 vs 9mm). Had a buddy, Green Beret selling his p938. I asked why, he said because he can unload his little 380 faster in a tighter spot. And he told me that means more than a lucky shot with full power. Its advice that other people in that "line of work" will tell you. I never bought a p938, and dont plan to. Again as others echoed. Listen to those that have done it, not the proverbial reload, ballistic processors. Just like people that went to college for something vs the ones that've actually done it for years. Experience is worth a ton in this aspect.

Again. This is just my own observation in this debate. Both are efficient. Just different purposes, like any other debate with guns/ammo.

Ginger, Ginger, Ginger...........................

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dd884
JMHO-YMMV

Please don't use such sophomoric responses as the above. Know one wants to get hit by any projection, be it bullet or golf ball. If 22lr were all that was needed then we would all carry that.

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NRA Cert. Inst. IDPA CSO

I'm just highlighting that there's a lot of nonsense surrounding handgun cartridges. Most popular defensive handgun cartridges are awful achieving the mythic "Stopping power." I'm sure most of us have read this story. But if you haven't:

Officer Down: The Peter Soulis Incident - Law Officer

Short story, officer shoots guy who took 22 hits of HP .40, 17 were center of mass and the guy was still fighting.

There's obviously a curve between extremes like 22 Short and 500 S&W Magnum.

The 22 short can easily get all shots on target but not be at all effective, the 500 magnum may be more effective, but irrelevant if you're then deaf, blind and concussed and miss. The power of the cartridge needs to be reconciled with shooter proficiency, capacity and convenience of the platform.