.38 Super in M&P 2.0 40 S&W...

[DocRock]

So, it turns out this is possible. But I strongly recommend against it...

Had a strange report on a round that was 3” or so outside a group and seemed “odd”. But it ejected and chambered the next 40 S&W and there was nothing to see when the mag was removed and the chamber cleared and a rod pushed down the barrel to check for obstruction.

However, look what I found when picking up brass.




(Fiocchi .38 Super Brass on left, misloaded spent .38 Super case fired in the M&P 40 S&W in the middle, Winchester 40 S&W fired case on right)


Reloads using Berry’s plated bullets with very similar profile in both (.38 Super left, .40 S&W right)


A rather annoyingly stupid mistake that reinforces the need to always be vigilant.

 

[fxvr5]

I'm surprised it fit in the 40 S&W magazine.

 

[Zaydok Allen]

I don’t see a problem.

 

[bannockburn]

DocRock

Can never be too careful while reloading or sorting out your ammo.

 

[silvermane_1]

I'm surprised it fit in the 40 S&W magazine.

Well a 38 Super case is only 1mm longer than 40 S&W.

 

[jmr40]

I did the same once when I mistakenly stuck a loaded G19 magazine in a G23. The 9mm round chambered and fired, but missed the target altogether, but did not cycle. I realized my mistake when I manually ejected the empty brass.

 

[JTQ]

I did the same once when I mistakenly stuck a loaded G19 magazine in a G23. The 9mm round chambered and fired, but missed the target altogether, but did not cycle. I realized my mistake when I manually ejected the empty brass.

I'm surprised this doesn't happen more often (well maybe it does and it's just not reported) with folks often having so many different models, and in different calibers, and all those mags basically look the same.

 

[Walkalong]

I see .40s fired in .45s and 9MMs fired in .40s at the range occasionally, they are not hard to spot. I splt a .41 Mag case in a .44 Mag revolver once. My older son has done the 9MM in a .40 thing.

 

[fxvr5]

Well a 38 Super case is only 1mm longer than 40 S&W.

Case length is irrelevant. Cartridge overall length is what matters and determines what will fit in the magazine.

 

[FlSwampRat]

DocRock
Can never be too careful while reloading or sorting out your ammo.

Nope! Back when I actually had the time in the evenings to reload I even shut off the radio during powder measuring. I only reloaded .357 so there was never a mixup on bullets, cases, etc. I just didn't want to accidentally double charge a case.
Once the cases were properly recharged with powder the radio went back on. Hard to accidentally put two bullets in one case.

 

[sparkyv]

I don’t see a problem.

except for reloading

 

[Zaydok Allen]

except for reloading

Just resize it and throw a little scotch tape around the case. I'm sure it'll chamber.

 

[Plan2Live]

Back when I was teaching concealed carry classes it was not uncommon to see someone load 9mm in their .40 caliber pistol. The first clue was usually the keyhole imprint on the target as the 9mm tumbled downrange.