10mm to .40 conversion?

[Gamecock]

I am fascinated by the new Dan Wesson Bruin, a long slide 10mm 1911. Will probably buy one.

I'd be interested in being able to convert it to .40 S&W for less serious work.

So, first I'd need a barrel. And probably a lighter recoil spring. Will .40 feed from 10mm magazines?

Any other concerns for conversion?

 

[litenlarry]

I am fascinated by the new Dan Wesson Bruin, a long slide 10mm 1911. Will probably buy one.

I'd be interested in being able to convert it to .40 S&W for less serious work.

So, first I'd need a barrel. And probably a lighter recoil spring. Will .40 feed from 10mm magazines?

Any other concerns for conversion?

Just a guess here, but the magazine would not feed properly the shorter OAL of the 40 cal.. Similar to the mag fed 22 rifles in the 60's, that would shoot 22 long and 22 long rifle but only with an adjustable feed ramp..

 

[robertrwalsh]

Once, just for the heck of it, I put a whole box of .40 thru a 10 mm glock model 20. Fed and functioned just fine, including ejecting and loading a fresh cartridge. From that I would say it is POSSIBLE (not necessarily likely) that it would work with the 10mm magazines. Obviously the deliberate use of the wrong ammo is not something to be encouraged on a regular basis.

 

[DWalt]

It might work OK as-is. It would be better if you found a .40 barrel of the same length that would fit. I'd bet the .40 would probably feed OK from the 10mm magazine, but I have not tried it. For me, the 9mm feeds just fine from a .38 Super magazine in my 1911, same could happen with a 10 mm mag, as the .40 is just a short 10mm. Likely that you will need a lighter recoil spring.

 

[bigggbbruce]

I shoot 10mm, when I want a bunny load I put less powder in my reloads. Cheapest way to go.

 

[Gamecock]

Once, just for the heck of it, I put a whole box of .40 thru a 10 mm glock model 20. Fed and functioned just fine, including ejecting and loading a fresh cartridge. From that I would say it is POSSIBLE (not necessarily likely) that it would work with the 10mm magazines. Obviously the deliberate use of the wrong ammo is not something to be encouraged on a regular basis.

10-4. Several of the automatic calibers are supposed to headspace on the case mouth, but will in fact headspace on the extractor if the chamber is too long.

I have a convertible long slide 9mm/38 Super. Conversion is barrel/recoil spring/magazine. As supplied by the maker. I assumed the different mag is needed, but maybe not. Never tried the Super mag with 9mm.

Sounds like converting the 10mm will be trial and error to determine what is needed. I'll start with a barrel and go from there. I'm looking forward to the project!

 

[sigp220.45]

Before the internet told me it was wrong, I would shoot .40s out of my 1076 pretty regularly. It always worked fine with the stock magazine and stock springs. I'm sure I was courting death and disaster, but somehow I survived.

 

[DWalt]

What happens when you shoot a .40 in a 10mm chamber (or a 9mm in a .38 Super chamber) is that the casing is held against the breech face by the extractor, and will allow it to be fired. Theoretically, that is not a good idea, and is not recommended. However, I have fired lots of 9mm rounds in .38 Super barrels with no difficulties. I have both a Colt GM and an EAA Witness in .38 Super. Both handle 9mm cartridges just fine in their .38 Super barrels using .38 Super magazines. I do use light recoil springs in both guns. But I cannot comment about the functional viability of using .40 S&W in a 10mm pistol and magazine, as I have not done that. I have nothing chambered in either of those calibers, nor do I want anything.

 

[Big E3]

I have 10mm to 40 conversion barrels for my Glock 29 and 20. I use the 10mm mags without any issues. I don't have any issues with the recoil springs needing to be changed out going from 10 to 40 either.

I have also heard that you can shoot 40 in a 10 barrel but have never tried it. I would think relying on the extractor to hold to ammo tight to the breech face could be hard on the extractor over time.

 

[Richard Simmons]

I shoot 10mm, when I want a bunny load I put less powder in my reloads. Cheapest way to go.

I agree. Simply download your 10mm to a lower power factor and pretend it's a .40S&W. Since you're not buying anything and using less powder you'd actually save money rather than spend money to convert.

 

[Gamecock]

I agree. Simply download your 10mm to a lower power factor and pretend it's a .40S&W. Since you're not buying anything and using less powder you'd actually save money rather than spend money to convert.

There is no overlap between 10mm load data and 40 S&W data. You can't load 10mm low enough.

 

[epj]

Once you get a barrel fitted, .40 1911 mags are readily available. I would think feeding would have to be a bit more reliable.

 

[Richard Simmons]

There is no overlap between 10mm load data and 40 S&W data. You can't load 10mm low enough.

Here's an example:



LoadData: 10MM Auto (Oregon Trail Handgun Data Reduced Action Loads) Charge and Load Information/Data for the 10MM Auto (Oregon Trail Handgun Data Reduced Action Loads).

10mm 155 gr at 1,017fps. Standard .40S&W load with 155gr runs from about 1,040 to close to 1,300. Seems like that would work? I realize the link won't allow you to see that specific charge without a subscription but I mean, there has to be loads out there some place.

 

[Gamecock]

Here's an example:



LoadData: 10MM Auto (Oregon Trail Handgun Data Reduced Action Loads) Charge and Load Information/Data for the 10MM Auto (Oregon Trail Handgun Data Reduced Action Loads).

10mm 155 gr at 1,017fps. Standard .40S&W load with 155gr runs from about 1,040 to close to 1,300. Seems like that would work? I realize the link won't allow you to see that specific charge without a subscription but I mean, there has to be loads out there some place.

Not in Speer #14.

 

[DWalt]

You can handload a 10mm to whatever power level you wish. However, why would you want to do that rather than buying .40 S&W ammo? The whole purpose of wanting to use .40 S&W is cheaper and more available ammunition.

 

[DR505]

You can handload a 10mm to whatever power level you wish. However, why would you want to do that rather than buying .40 S&W ammo? The whole purpose of wanting to use .40 S&W is cheaper and more available ammunition.

Your post is confusing. If you are hand loading, you don't buy factory ammo...you make your own. So if one has a supply of powder, primers, 10mm brass, and .40 caliber bullets, one can load them to whatever velocity they choose, within limits. This will still be cheaper than buying another barrel for the pistol AND buying factory ammo.

 

[DWalt]

You assume the OP is handloader, which was never stated. If he is not, then there is the expense of getting the necessary tools, equipment, and supplies. What's so confusing about that?

 

[DR505]

You assume the OP is handloader, which was never stated. If he is not, then there is the expense of getting the necessary tools, equipment, and supplies. What's so confusing about that?

Since the OP was discussing reloading data and referenced Speer #14 Reloading manual, it is a logical assumption to make, no? Hence the confusion engendered by your reply.