9mm vs .357mag
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fisherman66
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The 2" .357 speaks louder.
It is true that the 9mm is a good bit hotter than most folks give it credit for, but the .357Mag is going to be able to out-do it. You've got a lot more room for heavier bullets and even with a short barrel it should be able to outperform the 9mm.
You might be able to get comparable performance if you compare light bullet 9mm+P loads out of a 4.5" bbl with comparable weight bullets out of a .357Mag snubbie (especially since it's not uncommon to find that .357Mag SD loadings aren't pushing the top limits of what the caliber can do), but a glance at the ballistic figures from some of the "boutique" ammo sellers will convince you that once you get up past 125 gr bullets the .357 is going to come out ahead, even from a short bbl.
You might be able to get comparable performance if you compare light bullet 9mm+P loads out of a 4.5" bbl with comparable weight bullets out of a .357Mag snubbie (especially since it's not uncommon to find that .357Mag SD loadings aren't pushing the top limits of what the caliber can do), but a glance at the ballistic figures from some of the "boutique" ammo sellers will convince you that once you get up past 125 gr bullets the .357 is going to come out ahead, even from a short bbl.
I get 1204 fps out of my 360PD with Corbons 125 grain HP's.
brassfetcher got these results with:
So, yes, with 125 grain bullets, 9mm can be faster then the same weight bullet out of a snub. However, if the snub has a 3-4" barrel, the game seriously changes:
As you can see, the longer barrels move the 180 grain bullets 100 fps faster then the 9mm 125's, and, the 125 grain speer hps 400 fps faster then the 9mm...
brassfetcher got these results with:
So, yes, with 125 grain bullets, 9mm can be faster then the same weight bullet out of a snub. However, if the snub has a 3-4" barrel, the game seriously changes:
Below are buffalobores tests of their products:
As you can see, the longer barrels move the 180 grain bullets 100 fps faster then the 9mm 125's, and, the 125 grain speer hps 400 fps faster then the 9mm...
chris in va
New member
I was wondering that as well, thanks.
BTW anyone know the velocity of say...9mm HydraShok out of a carbine? I was told ~1600 but can't really confirm that.
BTW anyone know the velocity of say...9mm HydraShok out of a carbine? I was told ~1600 but can't really confirm that.
Yes you can indeed get performance similar to that of a snub .357 from a full-sized 9mm with hot loadings. Most "normal" 125grn .357 Magnums will exit a 2" barrel at 1200-1300fps which is also the typical muzzle velocity of the hotter +P and +P+ 9mm loadings in the same weight range from a 4-4.5" barrel. The advantages of the Magnum come into play when using a full sized revolver or using heavier bullets. A typical 125grn .357 Magnum will exit a 4" barrel at 1400fps or more and even out of a 2" barrel, a typical 158grn .357 will achieve velocities near or exceeding 1100fps. Likewise, manufacturers like Buffalo Bore and Double Tap load the .357 Magnum to significantly higher velocities with Buffalo Bore's heavier loadings still achieving 1476 fps from a 3" barrel and 1603 from a 4" barrel while the 9mm does not have as much margin for hotrodding with Buffalo Bore's hottest 124grn 9mm loading achieving only 1330fps from a 4.6" barrel.
#18indycolts
Moderator
if I needed a gun, any caliber....just give me either...really I don't care.
~1500 for a 115gr load would probably be more realistic. Most semi-auto pistol cartridges really don't get much benefit from the carbine length barrel. The .357 Magnum on the other hand is a different story. ~2200 fps for a 125gr load is probably "typical" and Buffalo Bore offers some loadings they claim are notably hotter.
CarbineCaleb
New member
If it's a real hot 9mm round like a Double Tap or a Buffalo Bore, versus a normal .357 Magnum round, I believe it.
If you are talking about a real hot .357 round though (which might be unusable from a small light snubbie), then the .357 looks like it still wins:
Double Tap makes about the fastest production ammo:
Double Tap 9mm, 124gr: 1310fps from a G17
Double Tap .357Mag, 125gr: 1425fps from a 1&7/8" J-Frame
Now I wouldn't want to shoot that Double Tap .357Mag stuff out of a J-Frame though.
If you are talking about a real hot .357 round though (which might be unusable from a small light snubbie), then the .357 looks like it still wins:
Double Tap makes about the fastest production ammo:
Double Tap 9mm, 124gr: 1310fps from a G17
Double Tap .357Mag, 125gr: 1425fps from a 1&7/8" J-Frame
Now I wouldn't want to shoot that Double Tap .357Mag stuff out of a J-Frame though.
CarbineCaleb
New member
Not much happens with "slower" rounds like 9mm, 40S&W or .45ACP in a carbine barrel. They just aren't accelerating very hard in the first place, and the tight barrel rifling imposes drag on them too, so something like a .45 can actually go slower from a longer barrel. You may pick up something like +100fps in the better cases with a 9mm.
.357, .41, and .44 Magnum cartridges are another story though. They will pick up a lot of extra speed.
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The reason that Magnum revolver rounds perform so much better performance in carbines has to do with both powder burn rates and case capacity. The autoloader rounds are usually loaded with faster burning powders as guns in these calibers typically have 5" or shorter barrels. The revolver rounds, on the other hand are commonly shot in guns with 6" and longer barrels and thus often loaded with slower burning powders to take advantage of these longer barrels. Because of this, the auto rounds often reach a point of diminishing return in carbine barrels as they burned all their powder and thus the extra barrel is only causing friction against the bullet and no more velocity gain is made. When handloading, the revolver rounds are more easily tailored to longer barrels as their larger case capacities and higer pressure limits allow more slow burning powder to be used while still maintaining safe pressures.
Here's an interesting site I'm probably the last one to see. Some of the .357 Mag. velocities seem a little slow in the shorter barrel lengths, but what do I know?