[Snagglepuss]

I was looking at at 10mm mags on the Tripp website. They list their 10mm mags as 10mm/.40S&W. Maybe a stupid question but does this mean my new 10mm CBOB can shoot .40S&W as a .357 revolver can shoot .38 specials?:scratch: :scratch:

 

[Chevy_Guy1977]

I'm not sure but...

I'm not quite sure about it since I don't have any 10mm gun, but I have read that revolvers chambered in 10mm can chamber and fire .40S&W. But it might be different in an automatic. I would think that if your pistol will feed the shorter round, and the extractor rim are the same, I dont see why they couldn't be used. I'm pretty sure the .40 is just a shorter 10mm case, used because the 10mm was usually loaded "down" anyway and the shorter case allowed it to fit in a smaller platform. One thing you'll definately want to check is if the .40 operates at a higher pressure than the 10mm.

But definately don't take my word for it, as I'm not sure about it. Do a little a research online, and hopefully someone with more firsthand knowledge will comment.
Chevy

 

[Iggy]

I think the general consensus is you can, but you shouldn't.

Both rounds headspace on the case mouth. Thus the only thing holding the 40 against the breach face is the extractor..

Not terribly good for extractors not to mention the bullet jumping from the shorter case to the rifling...

Somebody please correct me if I am wrong...

 

[Gary1911A1]

I believe you are 100% correct Iggy. I believe the same would be true of some pistols in .45ACP might be able to fire the 45GAP, but for the reasons you mention it would not be a good ideal.

 

[waffentomas]

Igg's right, but...............

I've fired thousands of .40s, through my Glock 20 & 29, and just bought a Kimber Eclipse. It only has 400 rounds through it, but 100 of them are .40s.

I understand the physics of why it may not be a good idea to do this, but I'm going to try and break my 10mms doing it - I don't care, I have lots of them.

Those darn gun rag writers write stuff like that without any empirical evidence that the extractors will actually break. They say "shouldn't", but I have never read an article where they actually managed to break one. They already hate the caliber, by and large, so what incentive do they have to say anything positive about it. May as well trash it some more.

I say shoot .40s in the 10mm.

Wow, that was a rant.

Tom

 

[Peter M. Eick]

An other issue to consider is that if you look at your 10mm down the barrel you will see a chamber edge or step that you headspace against. Now your 40's are too short. Thus the bullet has to jump the distance from the end of the loaded cartraige (1.135 if I remember right) to the end of the chamber (1.255 again if I remember right).

So what do you think the odds are that the bullet is going to land straight on?

My worry in doing this is the potential damage to the 10mm chamber edge.

If you are still unsure, pull out your 357 mag and look down the cylinder and then compare to your 10mm barrel.

As a buddy at work always says "no good can come from this".

 

[Deadmarsh]

Mags?

In your seach to fill up the grip space of your DW, don't overlook MetalForm. IMHO, they are the best and only magazine for CCW. At the range, who cares. FWIW, the MetalForm round follower, welded baseplate are bulletproof...good luck


Dead

 

[Dave Severns]

Iggy's correct. While it can theoretically be done, it's not a smart idea. One thing that hasn't been mentioned here is that accuracy also suffers. The cartridge was designed to headspace off of the case mouth, and not dangle off the end of the extractor hook.

Careful with promoting "breaking" your guns around here, waffentomas! We promote gun safety here. BTW, extractors do break, and more often than one might think. Period.

 

[10mm_Bob]

I have a friend who does it by seating the bullets higher in the .40sw case (thus, removing the gap). I think it's a bad idea, even though he has had no problems to date.

I am firmly in the "don't do it" column on this one. If cost is a concern, then I suggest learning to reload. I shoot 10mm reloads for less than $7 per box. I'm not going to open the "to reload, or not to reload" question on this forum, but I think in this case it's a safer alternative than shooting the wrong ammo in the gun to save a few bucks. JMHO. Be safe. If you choose to reload, then PLEASE learn from an experienced reloader how to do it right. The NRA offers classes if you don't know anyone. Just visit their website at www.nra.org to find an instructor in your area.

Bob

 

[El Hombre]

I think the best solution is to get a barrel in 40 and change it out when you want.

 

[HiVelSword]

I think the best solution is to get a barrel in 40 and change it out when you want.

Well said.

I thought EVERYONE has heard of the term, "better safe than sorry". You would think that would apply to firearms experimentation too.

 

[Snagglepuss]

Thanks everyone, it appears my question is anwered, I will stick with 10mm. Do you think I can use a .40 mag in the 10mm if it is not posted so. I have had a lot of success with CMC powermags but they do not list 10mm. I would like to stick with CMC. If not what do you think of Cobra Mags?

I ordered some 10mm from Lancer Custom Ammo, very inexpensive, will let you know how they work out. Got them for the range.

 

[Cyclone]

I know CMC makes 10mm mags - ShootingStar version I believe.

 

[Snagglepuss]

Yeah, I have found those but I am partial to the powermags. Thanks

 

[10mm_Bob]

I think the best solution is to get a barrel in 40 and change it out when you want.

Not sure it's this simple. I think with 1911s it requires the entire slide assembly in most cases. Hopefully, Dave can answer this for sure. It's definitely not like Glocks. Everything needs to be fitted.

 

[Noklue3]

I have to admit I do not understand this whole thing. If you want a .40 then buy one. If you want a 10mm then buy that.
Why push the limits of the design by trying other calibers that are marginally able to be shot with the pistol ...abit unsafe as stated by some that are in the know.
I have a Blackhawk that I use .357 and .38's but that is a different story than trying to use what has been suggested here. In a revolver, the problems noted are not an issue as it is with an auto as I am sure you all know.

Guess I am just missing the point.

Take care,
Art

 

[HiVelSword]

Not sure it's this simple. I think with 1911s it requires the entire slide assembly in most cases. Hopefully, Dave can answer this for sure. It's definitely not like Glocks. Everything needs to be fitted.

You can swap barrels. If they were fit to the slide it would be more accurate but drop ins work. a 10mm 1911 can shoot .40 S&W, .357 SIG and 9x25mm Dillon. Four barrels and one slide. The 10mm magazines will work with the 9x25. .357 SIG will work in the .40 S&W mags. Yes, springs need to be swapped too.

Why four barrels and one slide? Because the breach face is the same for all four cartridges.

If you have a .38 Super you can swap barrels and mags and be able to shoot 9x23, 9mm, 9x21, .356 TSW, .38 supercomp, 9mm supercomp etc.

If you have a .45 ACP you can swap barrels and mags and shoot .400 Cor Bon, .45 Super (doesn't actually require a new barrel, just minor tweaking), .40 Super, .460 Rowland and .38 Casull etc.

 

[Gary1911A1]

I too load .40S&W long to use 10MM Mags and to have better feeding in a 1911, but I do it in a 1911 with a .40S&W barrel. 10MM Bob, I think your friend still has the .40S&W cases being held by the extractor so when the firing pin hits the primer the round it still goes forward putting strss on the extractor. Tell your friend to buy a .40S&W barrel.

 

[servarw]

You can but IGGY is right, don’t. To make a long story short it has to do with the headspace dimension on the case mouth in reference to the barrel chamber. You can get away with using 10mm mags in a 40, “sometimes”. If ou want to shoot 40's have another barrel fit.

Thanks,
Bob
DWF/CZ

 

[Chevy_Guy1977]

I believe you are 100% correct Iggy. I believe the same would be true of some pistols in .45ACP might be able to fire the 45GAP, but for the reasons you mention it would not be a good ideal.

Actually, the two .45's are a completely different case. The extractor groove is way different, and the case is for higher pressures. If you have the chance to see the two side by side, you'll see they are quite different.
Chevy