FBI load in a 10mm?

MADISON · January 19, 2008, 09:50 AM

Years ago, there was a controversy over the safety of the .40 S&W FBI load being safe in a 10mm case/gun.
If I trade a S&W .357 in for either a .40 S&W or a 10MM is the FBI load
[950 180 gr. bullet at 950 FPS safe in a 10MM?

oldscot3 · January 19, 2008, 09:56 AM

I'm not clear on the question, are you asking if you can load and fire 40 S&W ammunition in a pistol chambered for 10mm Auto, or are you asking if a 10mm Auto moderately loaded to 950fps is safe?

Sevens · January 19, 2008, 06:35 PM

I agree--I'm not quite sure what the question is asking.

The "FBI load in a 10mm" is the entire reason the .40 S&W was created in the first place. When the FBI took delivery of their new S&W 10s, they quickly found the recoil, flip, flash, and everything that goes with a hot-as-hell round was too much for their agents to master. So after paying for a huge new pistol contract, they asked the ammo companies to dumb down the round so that it was much more manageable.

They dumbed down the ammo and then S&W realized that if the ammo was going to be dumbed down, they would be much better off shortening the length, because they could then build a ten millimeter diameter round on a smaller platform that didn't have to be overbuilt to handle the scorching original 10mm load.

S&W was so convinced that their new caliber was the best answer that they took their own 10mm pistols out of production. Many agree that the Smith & Wesson 10's were the best 10s on the market, and S&W simply ended them so as not to compete with their own agenda of pushing the .40 S&W.

The fact is, most of the "factory" 10mm ammo on the market today IS that dumbed down light load. Winchester Silvertips are nicely hot, and the stuff Double Tap ammo is the REAL deal, but most other factory 10mm ammo you'll find (and that includes Federal Hydra-shock) is, well, pretty wimpy for a true 10mm.

If you are asking whether a 180-grain bullet at 950 fps is safe in a 10mm, the answer is-- yes, by a country mile. A true 10mm oughta be kicking out a 180-grainer at 1200+ FPS.

You won't match the power of a .357 magnum with a .40 S&W caliber pistol. You can get there with a 10mm, but it's a close race.

crowbeaner · January 19, 2008, 06:41 PM

For a nice practice load in the 10mm try a 175 SWC over 7.5 of SR 4756. If you want power, try some AA#7 with the 180 JHP. Work up and be sure your pistol has a fully supported chamber that encloses the cartridge head for safety (NOT A GLOCK!). CB.

Musketeer · January 19, 2008, 09:26 PM

You can safely shoot the "FBI Load" in a 10mm. In fact, unless you go to Double Tap, CorBOn or Buffalo Bore, they only thing you are likely to get in 10mm is the "FBI Load"

It is NOT SAFE to shoot a .40S&W (shorter case than 10mm) out of a 10mm because the BULLET ISN'T DESIGNED TO FIT THE GUN.

MADISON · January 20, 2008, 09:30 AM

OLDSCOT3:
The .40 S&W uses a smaller case than the 10mm.
When people started reloading the 10mm there was concern over the extra space causes the round[s] to top explode.
Is it safe to load in a 10mm or do I need to buy a 40 S&W?

oldscot3 · January 20, 2008, 12:36 PM

I'm sorry if I still don't quite understand but maybe this will help...

The 10mm Auto came first , its very flexible, easy and straightforward to load, just follow published manual specs. It can be safely loaded from mild to wild.

As mentioned above, the 40 S&W came second, it was basically just a shortened 10mm case which provided all the capacity that was necessary to match the ballistics of the FBI's 10mm Auto load. In addition, since the OAL was shorter, it fit nicely in the 9mm sized pistols which were all the rage then. Manufacturers could quickly get in on the 40 cal. trend without having to abandon their line of 9mm pistols or even have to develop a larger weapon that fit the 10mm Auto size cartridge.

When handloading the 40 S&W you may use up to a 180 gr. bullet, the heavier bullets (200 gr.) which are also longer, may not be used , because when loaded into a 40 S&W case their base extends down to the webbing and causes an external bulge. Also, I'm sure you can imagine, powder space would be very limited. Likely, such a handload wouldn't even chamber, but if it were somehow crammed in, I could foresee problems! Again, just follow guidelines in published manuals.

Hope, this helps, I have weapons for both rounds, load both, never had a problem with either and find both to be highly effective and useful.

Musketeer · January 20, 2008, 12:42 PM

I THINK what he is referring to is a fear that the added empty volume in a 10mm case loaded to only .40S&W levels will have the effect of a light charge with added flame front. The result would be the powder explodes instead of burns.

Is that what you are talking about Madison?

The answer is... Do not worry. Load the 10mm light within the specs of the book and you are fine. The loadings that duplicate the 40S&W are not a problem and were developed using the 10mm before the Short and Weak case was ever developed. The S&W was developed to reduce the frame size of the gun, not make using the lighter load safer.

**Mike Irwin** · January 20, 2008, 12:44 PM

"The "FBI load in a 10mm" is the entire reason the .40 S&W was created in the first place."

The .40 was already well into design and testing by the time the FBI settled on the 10mm Lite load.

S&W saw the potential for a shorter 10mm round while the FBI was still trying to figure out if it even wanted a 10mm or not.

Wildcatters in the mid 1980s had already started the process, even before the Miami shootout that pushed FBI towards the 10mm in the first place, of developing the .40 after reports came out about Norma ammo cracking the Colt Deltas.

N.M. Edmands · January 20, 2008, 04:42 PM

Mike, wasn't there a problem of accuracy and consistency with the powders and projectiles available at the time that helped drive the 40 S+W development?

[in ref to the 10"lite" loadings]

**Mike Irwin** · January 20, 2008, 09:15 PM

"Mike, wasn't there a problem of accuracy and consistency with the powders and projectiles available at the time that helped drive the 40 S+W development?
[in ref to the 10"lite" loadings]"

Not to any great degree. There probably were some issues early on in development, but testing with various combinations of powder and projectiles very likely solved any early issues there might have been.

Remember, the FBI load was offered commercially by at least Winchester and Federal for a number of years with no reported problems.

January 19, 2008, 09:50 AM	#1
MADISON Senior Member Join Date: January 1, 2000 Location: Roanoke, Virginia Posts: 2,678	FBI load in a 10mm? Years ago, there was a controversy over the safety of the .40 S&W FBI load being safe in a 10mm case/gun. If I trade a S&W .357 in for either a .40 S&W or a 10MM is the FBI load [950 180 gr. bullet at 950 FPS safe in a 10MM?

January 19, 2008, 09:56 AM	#2
oldscot3 Senior Member Join Date: July 1, 2007 Location: texas Posts: 997	I'm not clear on the question, are you asking if you can load and fire 40 S&W ammunition in a pistol chambered for 10mm Auto, or are you asking if a 10mm Auto moderately loaded to 950fps is safe? Last edited by oldscot3; January 19, 2008 at 12:22 PM.

January 19, 2008, 06:35 PM	#3
Sevens Senior Member Join Date: July 28, 2007 Location: Ohio Posts: 11,756	I agree--I'm not quite sure what the question is asking. The "FBI load in a 10mm" is the entire reason the .40 S&W was created in the first place. When the FBI took delivery of their new S&W 10s, they quickly found the recoil, flip, flash, and everything that goes with a hot-as-hell round was too much for their agents to master. So after paying for a huge new pistol contract, they asked the ammo companies to dumb down the round so that it was much more manageable. They dumbed down the ammo and then S&W realized that if the ammo was going to be dumbed down, they would be much better off shortening the length, because they could then build a ten millimeter diameter round on a smaller platform that didn't have to be overbuilt to handle the scorching original 10mm load. S&W was so convinced that their new caliber was the best answer that they took their own 10mm pistols out of production. Many agree that the Smith & Wesson 10's were the best 10s on the market, and S&W simply ended them so as not to compete with their own agenda of pushing the .40 S&W. The fact is, most of the "factory" 10mm ammo on the market today IS that dumbed down light load. Winchester Silvertips are nicely hot, and the stuff Double Tap ammo is the REAL deal, but most other factory 10mm ammo you'll find (and that includes Federal Hydra-shock) is, well, pretty wimpy for a true 10mm. If you are asking whether a 180-grain bullet at 950 fps is safe in a 10mm, the answer is-- yes, by a country mile. A true 10mm oughta be kicking out a 180-grainer at 1200+ FPS. You won't match the power of a .357 magnum with a .40 S&W caliber pistol. You can get there with a 10mm, but it's a close race. __________________ *Attention Brass rats and other reloaders:* I really need .327 Federal Magnum brass, no lot size too small. Tell me what caliber you need and I'll see what I have to swap. PM me and we'll discuss.

January 19, 2008, 06:41 PM	#4
crowbeaner Senior Member Join Date: June 4, 2007 Location: Upstate SC Posts: 1,943	For a nice practice load in the 10mm try a 175 SWC over 7.5 of SR 4756. If you want power, try some AA#7 with the 180 JHP. Work up and be sure your pistol has a fully supported chamber that encloses the cartridge head for safety (NOT A GLOCK!). CB. __________________ If you want your children to follow in your footsteps, be careful where you walk. Beware the man that only owns one gun; he probably knows how to use it. I just hope my ship comes in before my dock rots.

January 19, 2008, 09:26 PM	#5
Musketeer Senior Member Join Date: September 12, 2005 Posts: 3,733	You can safely shoot the "FBI Load" in a 10mm. In fact, unless you go to Double Tap, CorBOn or Buffalo Bore, they only thing you are likely to get in 10mm is the "FBI Load" It is NOT SAFE to shoot a .40S&W (shorter case than 10mm) out of a 10mm because the BULLET ISN'T DESIGNED TO FIT THE GUN. __________________ "Religions are all alike - founded upon fables and mythologies." Thomas Jefferson "The way to see by faith is to shut the eye of reason." Benjamin Franklin

January 20, 2008, 09:30 AM	#6
MADISON Senior Member Join Date: January 1, 2000 Location: Roanoke, Virginia Posts: 2,678	FBI 10mm load OLDSCOT3: The .40 S&W uses a smaller case than the 10mm. When people started reloading the 10mm there was concern over the extra space causes the round[s] to top explode. Is it safe to load in a 10mm or do I need to buy a 40 S&W?

January 20, 2008, 12:36 PM	#7
oldscot3 Senior Member Join Date: July 1, 2007 Location: texas Posts: 997	I'm sorry if I still don't quite understand but maybe this will help... The 10mm Auto came first , its very flexible, easy and straightforward to load, just follow published manual specs. It can be safely loaded from mild to wild. As mentioned above, the 40 S&W came second, it was basically just a shortened 10mm case which provided all the capacity that was necessary to match the ballistics of the FBI's 10mm Auto load. In addition, since the OAL was shorter, it fit nicely in the 9mm sized pistols which were all the rage then. Manufacturers could quickly get in on the 40 cal. trend without having to abandon their line of 9mm pistols or even have to develop a larger weapon that fit the 10mm Auto size cartridge. When handloading the 40 S&W you may use up to a 180 gr. bullet, the heavier bullets (200 gr.) which are also longer, may not be used , because when loaded into a 40 S&W case their base extends down to the webbing and causes an external bulge. Also, I'm sure you can imagine, powder space would be very limited. Likely, such a handload wouldn't even chamber, but if it were somehow crammed in, I could foresee problems! Again, just follow guidelines in published manuals. Hope, this helps, I have weapons for both rounds, load both, never had a problem with either and find both to be highly effective and useful.

January 20, 2008, 12:42 PM	#8
Musketeer Senior Member Join Date: September 12, 2005 Posts: 3,733	I THINK what he is referring to is a fear that the added empty volume in a 10mm case loaded to only .40S&W levels will have the effect of a light charge with added flame front. The result would be the powder explodes instead of burns. Is that what you are talking about Madison? The answer is... Do not worry. Load the 10mm light within the specs of the book and you are fine. The loadings that duplicate the 40S&W are not a problem and were developed using the 10mm before the Short and Weak case was ever developed. The S&W was developed to reduce the frame size of the gun, not make using the lighter load safer. __________________ "Religions are all alike - founded upon fables and mythologies." Thomas Jefferson "The way to see by faith is to shut the eye of reason." Benjamin Franklin

January 20, 2008, 12:44 PM	#9
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	"The "FBI load in a 10mm" is the entire reason the .40 S&W was created in the first place." The .40 was already well into design and testing by the time the FBI settled on the 10mm Lite load. S&W saw the potential for a shorter 10mm round while the FBI was still trying to figure out if it even wanted a 10mm or not. Wildcatters in the mid 1980s had already started the process, even before the Miami shootout that pushed FBI towards the 10mm in the first place, of developing the .40 after reports came out about Norma ammo cracking the Colt Deltas. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

January 20, 2008, 04:42 PM	#10
N.M. Edmands Member Join Date: December 2, 2001 Location: Yarnell,Arizona Posts: 48	Mike, wasn't there a problem of accuracy and consistency with the powders and projectiles available at the time that helped drive the 40 S+W development? [in ref to the 10"lite" loadings] __________________ Nat "Some where something incredible is waiting to be known" -Carl Sagan "It aint how good you shoot,it's how cool you look doing it." -Fred Sayre 1994

January 20, 2008, 09:15 PM	#11
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	"Mike, wasn't there a problem of accuracy and consistency with the powders and projectiles available at the time that helped drive the 40 S+W development? [in ref to the 10"lite" loadings]" Not to any great degree. There probably were some issues early on in development, but testing with various combinations of powder and projectiles very likely solved any early issues there might have been. Remember, the FBI load was offered commercially by at least Winchester and Federal for a number of years with no reported problems. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.