CS40 Conversion To 10MM

[Big Shrek]

Just for fun, last night I installed my 1006 top end on my CS40.

Why?

I wanted to find out if a CS45 magazine would feed 10mm cartridges without any modifications.

You all know by now that CS40 and CS45 magazines and top ends interchange, don't you?

I hand cycled the entire magazine through the action.

I think this means there is no need to mangle CS40 mags.

I've had a CS40 for a very long time, and as much as I enjoy mods to pistols, the CS40 to 10mm conversion is one I would not do for two reasons.

1) The CS40s were the lowest production of the CS models.

2) Even with a buffer, the 10mm cartridge unmercifully batters the aluminum frame.

But hey, they're your CS40 pistols to modify and I commend you guys for taking the initiative.

John

That brings two questions to my mind...will a standard 45 mag
hold the 10mm cartridge without issue during firing?
Definitely testable. Needs to be tested, in fact.

Second, would then, by extension, the 10mm mags fit in a CS40 or CS45??
Nope, because there are two tabs on the 10mm mags that prevent them
from being fully inserted. And the 10mm mag has a double mag catch...

And then there is another question about Frame Battering.
For those that have had theirs converted for awhile, can you take
a few pics of the frame stops and show us if there is any issue thusfar?
And roughly how many rounds have been fired so far??


Frankly I think it calls for a torture test of a "Beater" CS40 frame,
we need to find one that's cosmetically been abused and slap a 10mm slide
onto it and then literally fire it until the frame stops fail.
That would alleviate all questions about whether or not the aluminum
frame can handle those full power 10mm loads.

Sounds like a project that would work well with the next meetup of
3rd Gen worshippers...do we have those??
Everyone bring a box of 10mm for use in the torture test

 

[Big Shrek]

Of course, if S&W would simply "Nut Up" and produce
the M&P 2.0 10mm...in both full size & compact...
none of this would be necessary

 

[TTSH]

Sounds like a project that would work well with the next meetup of 3rd Gen worshipers...do we have those??

We need to work on that!

 

[TTSH]

Their inventory is obviously not live. You can put in an order for 1,000 of them and the order still processes... ... but I doubt they have that many. I wonder how many they do have?

I think I better call them first thing Monday morning!

Confirmed by phone what I guess we already knew: They are all sold out.

 

[tlawler]

Found a local smith (over the phone) that told me he could ream my barrel. He wanted to know the details and I gave him all the info on the gun. He told me that "The gun will be worthless if it works! It will be a snub nose 41 and the barrel for a 40 S&W can't handle that abuse."
I told him about the info on here and he said "The internet hurts or kills people every day." I told him I'd take my chances, just ream the barrel and I'll take responsibility.
Dropping barrel off next week.
Hope a few of you got in on the $25 mag deal.

How is the conversion coming along? I'm getting all the pieces and parts together for mine.

 

[oldman10mm]

referring back to post#61,a torture test for a CS40 converted to 10mm ??? A totally unrealistic test. Once it's built,tested, & proven,it's only gonna be a defensive and /or seldom used weapon. If you want to shoot 10mm at the range,use a 10xx series or some other manufactured for 10mm.

 

[tlawler]

referring back to post#61,a torture test for a CS40 converted to 10mm ??? A totally unrealistic test. Once it's built,tested, & proven,it's only gonna be a defensive and /or seldom used weapon. If you want to shoot 10mm at the range,use a 10xx series or some other manufactured for 10mm.

I wish the OP and others would weigh in on how they have held up. I would be ok with just shooting light loads in it for practice and carrying it with full power, hoping I would never have to use it. I just like the idea of a single stack 10mm pocket rocket for concealed carry.

 

[armorer951]

While I'm not an engineer, I believe the difference in the SAAMI max pressure specs: 10mm @ 37,500, and the .40 S&W @ 35000, are close enough that the heavier pressure of the 10mm can be accomodated by the smaller frame of the CS series and the 4053/4054 by beefing up the recoil system to the point where the slide doesn't batter the frame. These pressures will still take a toll on the frame and other components, but I believe can be tolerated if a regimen suggested before was strictly adhered to......light loads are used for practice, and the heavier self defense loads are carried, but used infrequently. Of course, close attention would have to be paid to proper cleaning and lubrication, which would also tend to mitigate wear and tear.

I've not noticed contact battering or damage on my 4053 10mm conversion, but I've only fired hardball, or what most people consider factory "range" ammo, and I'm using a very aggressive recoil spring combination. I can't really comment on what a steady diet of defense loads would do to to the frame and internal parts.

 

[oldman10mm]

SAAMI pressure for the 40 is 35,000,37,500 for the 10. Most,if not all,conversions have a heavier recoil spring install. A light/reduced load for practice with a heavier recoil spring might not have full cycle to allow proper full ejection.
And where would you get that 'light load' or are you talking about all the 'watered down' 10mm loads currently on the market. The original ammo for 10mm was made by Norma and it was hot. All the currently available 10mm ammo from the majors like Winchester and Remington are weak(stronger than 40 but weaker than the original Norma ammo). I think Federal came out with a true 10mm hot load. I reload so I can load a 10 down to 40 power or up to 'nuclear'.

 

[toddstang]

referring back to post#61,a torture test for a CS40 converted to 10mm ??? A totally unrealistic test. Once it's built,tested, & proven,it's only gonna be a defensive and /or seldom used weapon. If you want to shoot 10mm at the range,use a 10xx series or some other manufactured for 10mm.

I agree but wish that some original conversion people would update.

 

[Big Shrek]

I agree but wish that some original conversion people would update.

Amen to that, with Pics.

 

[mitchjt]

This has been a good discussion on converting 40s to 10mm. I made two of these conversions about three years ago, one for me and one for my son. We have had fun shooting and showing off these pistols. One of the posters above commented about matching up a 4010 slide with a 4516 frame. I tried that and it went together just fine. The 4010 magazine would not go in the frame because of the bumps on the side of the magazine. I had a 1066 magazine laying around that I removed its bumps for using in the 4010. This magazine would go into the 4516 frame but would not securely latch onto the magazine catch because it is a little too narrow. I may attach some sort of shim to the one side to thicken it up and press it to the side with the catch. Any one try this?

 

[JohnHL]

I have found that the 45 magazines will hand-cycle 10mm cartridges through a 10mm slide mounted on a 45 frame.

No live fire tests.... yet.

John

 

[TNZ71]

Just for fun, last night I installed my 1006 top end on my CS40.

Why?

I wanted to find out if a CS45 magazine would feed 10mm cartridges without any modifications.

You all know by now that CS40 and CS45 magazines and top ends interchange, don't you?

I hand cycled the entire magazine through the action.

I think this means there is no need to mangle CS40 mags.

I've had a CS40 for a very long time, and as much as I enjoy mods to pistols, the CS40 to 10mm conversion is one I would not do for two reasons.

1) The CS40s were the lowest production of the CS models.

2) Even with a buffer, the 10mm cartridge unmercifully batters the aluminum frame.

But hey, they're your CS40 pistols to modify and I commend you guys for taking the initiative.

John

It's been fun reading this thread over the past few months. And today I found a two tone CS40 and put it in layaway. Now where can I find magazines. And I probably won't convert it.

 

[James&theGiant1911]

I agree with the post above, ya'll have found a new way to develop a live hand grenade. I would not want to use this everyday, have any of you all ever looked at the 10xx Smiths closely?

they are built like tanks. this is a bad idea.

 

[oldman10mm]

The S&Ws' that are 'modifyable' to 10mm are built like tanks,the CS40,4013,4014,4053,4054. They start with barrel blanks for the 45 platform and then only being opened up for 40,very heavy wall results. Only issues to address are the recoil spring,buffer,and magazine mods.

 

[BLUEDOT37]

Hey, that's my picture!

I forgive you.

.

4013 vs 4013TSW barrel, breach view

(-01a)

.

4013 vs 4013TSW barrel, muzzle view

(-02a)

.

 

[oldman10mm]

Yes,your picture,sorry. I needed the text changed.

 

[JohnHL]

The S&Ws' that are 'modifyable' to 10mm are built like tanks,the CS40,4013,4014,4053,4054.

Sure.

If tanks are made of aluminum.

John

 

[JohnHL]

I posted this message in another thread.
It goes into greater detail about my objections to the CS40 10mm conversion:

Brother colt_saa, thanks for your comment and the opportunity to express my objections to the CS10 conversion.

I am happy to defer to your greater experience in this area as I have not only "failed to re-spring the gun as specified in the various conversion threads here on the Forum", I have completely neglected to make the CS40 to 10mm conversion in its entirety.

Please be assured that I would love to do it because I love multi caliber conversions (I've converted my 40s to 357Sig).

And my efforts with the 357Sig conversion coupled with experiences and observations have persuaded me that the upside of the CS10 conversion is somewhat outweighed by the downside.

My first concern is that S&W never chose to build a 10mm on any alloy frame, much less such a light one. (Yeah, I know. Nobody had ever landed on the moon before. That didn't make it impossible.)

My second concern is the 10mm cartridge itself.
Relative to diameter, it's a long cartridge so a lot of the powder burns outside of the short barrel.
So I'm not so sure there is much of a ballistic advantage.
It also out pressures the the 40s&w round by 3000psi (35k vs. 38k).
But it's not so much the peak pressure but where in the pressure curve that peak comes.
Being a pistol cartridge with fast powder, the pressure peak occurs early in the curve when the pistol is transitioning from locked to unlocked. (Remember the CS40 has no locking lug on the barrel.)

This brings us to the recoil spring you mentioned earlier.
The standard CS40/45 recoil spring is rated at 17 lbs. (by my measurement).
The 1006 spring is 22 lbs. with a heavier (read higher inertia) slide.
Either way, the springs are not at full resistance so early in the recoil cycle.
In my experiments with the 357Sig (40k psi) during unlocking, I found the barrel smacked the alloy frame of a 4003 hard enough to leave a mark even with the 22 lb Wolff recoil spring installed.
I therefore only install my 357Sig barrels on Steel frame pistols like the 4006.
So the requirement for a "shok-buff" to protect the CS40 frame hardly fills me with confidence.

Then there is the issue of the slide rebounding at higher than normal velocities off of the aforementioned recoil buffer and accelerated by the "hyper-spring" back to smash hard into the slide stop.
A common place for cracks to develop on these alloy frames is the thin area above the slide stop shaft hole on the left side of the frame.

My final objection is the relative scarcity of these pistols and their associated components.
The CS40 was produced in the fewest numbers of all the CS models and for the shortest period of time.
And they ain't makin' no more of 'em!

Ream that chamber and that barrel will never be original again.
Rip that spacer out of the magazine, ditto. (Although some quick and dirty testing seems to suggest that CS45 magazines will feed 10mm cartridges.)
Excessively peen or (heaven forbid) crack that frame and the CS40s still out there become even more rare.

Bottom line is, these are your guns.
Modify them how you like.
I envy your CS10.
I simply can't justify the conversion.

John