[101Combat Vet]

I have heard rumors of firing 9mm ammo through a .40 just wondering if this is true and what kind of damage if any it would cause???? Thanks in advance-Jason

 

[Mrgrinch233]

I'm no expert, but I wouldn't advise it. Lets see if some of our experts chime in. I'd really like to hear what they have to say.

 

[Dan Burwell]

it can be done. It will not cycle the slide and accuracy sucks (imagine that). I would not set out to do it intentionally but it doesn't seem to harm the gun. The potential is there for a bullet to get lodged in the barrel so again I wouldn't set out to do it intentionally

 

[raz-0]

It has happened on accident. The case usually ruptures, it doesn't sound right at all, and it isn't what I would call accurate. I know of at least one case where some of the gasses vented in a fairly unfriendly manner which did no real harm, but was not pleasant (shooter was wearing eyes and ears as they should).



It is not something that you WANT to do. But it has happened, and in all the cases I know of, both gun and shooter survived without permanent harm.

 

[ClosetCaseNerd]

it can be done. It will not cycle the slide and accuracy sucks (imagine that). I would not set out to do it intentionally but it doesn't seem to harm the gun. The potential is there for a bullet to get lodged in the barrel so again I wouldn't set out to do it intentionally

Do you mean the striker to push the smaller diameter complete cartridge into the barrel, without igniting the cartridge?



Is using the 9mm in a .40 barrel feasible if say, SHTF and you happened upon 9mm ammo?

 

[jackal99]

Extremely advise against trying to do this. The reason the case will rupture is because it is in the chamber unsupported. Yes, a case or cartridge can get lodged in the barrel without ejecting. And it is possible for the weapon to be fired after another cartridge is fed into the chamber. This can be extremely dangerous. It may not appear to visually be any damage to the weapon after it is done but it is not adviseable to shoot the weapon again at least until the barrel can be inspected. It needs to be run through non destructive testing and be xrayed for microscopic cracks that would possibly lead to chamber failure. I do understand that we have all heard about so and so shooting this and that in their gun that was made to shoot xyz and it still shoots good today and has never had a problem with it. Yes that may be the case but they are still a dumbass or someone has lied to you. But whatever you do don't take a chance on harming yourself or someone else. I can hear some of you that are reading this now saying it's not going to hurt me. Well to be perfectly honest if you don't listen to this I really don't care because you were warned what I do care about is the friend, relative, or child that knows nothing about what has happened to the gun and you let them shoot it and fails. Then you have to live with what you done. Just imagine shrapnel being thrown into your face from a chamber failure. Not a pretty image in your mind. Do the right thing. If it's not made for your gun don't shoot it in it. I know that's why we have all sorts of safety and hunter education classes to warn people against such things. Yes I understand that accidents can happen and cartidges can be mixed. Attention to detail my fellow shooters let's not give the anti's more reasons to try to take away our guns.

 

[coltman1985]

If one were to place a 9mm in a .40 it would just run out to the other end of the bar. The danger comes in it not exiting before another round was chamber and fired. I have not done this in my M&P but, my Glock 22 I tried it to see... it just ran out the other end!

 

[luvmy40]

Is using the 9mm in a .40 barrel feasible if say, SHTF and you happened upon 9mm ammo?

If the SHTF and you have time to find 9mm, load a mag & cocknrock, you have time to get the HE!! out or find the right ammo. I would hope that you (we) all take enough time when gearing up to ensure that our spare mags match our carry. JMHO



I understand the original question as it could be fairly easy to accidentally lock a loaded 9mm mag into a .40. And as stated by others. One round probably won't ruin the gun but it can't be especially good for it either.



$.02

 

[ClosetCaseNerd]

Wasn't the SHTF I was thinking of, I was thinking..mad max style SHTF

. Your in a long term survival situation, have run out of .40, but have happened upon 9mm...

 

[luvmy40]

Wasn't the SHTF I was thinking of, I was thinking..mad max style SHTF

. Your in a long term survival situation, have run out of .40, but have happened upon 9mm...

Gotcha, I'll have to leave that one up to the real experts.

But just as thought. Since a 9mm case fits nicely into a .40 case, it would take a good bit of luck for the extractor lock onto the round and hold it secure enough to fire.

 

[Dan Burwell]

I don't think the velocity would be enough to do squat to a human other than maybe put an eye out. :wink:

 

[ClosetCaseNerd]

Thanks Dan, thats kind of what I was thinking.