Converted my Shield .40 to 9mm

[robkarrob]

I checked the measurements of both barrels very carefully and could only find two differences between the 40 and 9 barrels: the bore and the tang/tab width at the peep hole. The 40's tab width is .425 and the 9mm is .399, for a difference of .026. This means to make the 40 tab width exactly the same as the 9mm, .026 needs to be removed.

My opinion would to be grind .010 off one side of the tab. Measure to make sure you have it at .415. Then grind .010 off the other side making the width .405. The easiest way would be to grind off material using the side of a bench grinder wheel. This is only .020 removed but it may work as there is some side to side movement with the 9mm barrel in the 9mm slide. It should fit at this width, but may be a little tight. Check the fit in the 9mm slide. If it fits in then assemble and test racking. If it racks OK, then see if it feeds OK. From there is range testing. If it doesn't fit right, then take .002 off each side in a similar way as above. This way you are keeping the tab centered.

With my ability to compare the dimensions of the two barrels, I see no reason that the 40 barrel into the 9mm slide would not work. It should work just as well as the 9mm barrel into the 40 slide, except that the width of the tang/tab must be reduced a bit. The 9mm slide has a slightly narrower width for the tang/tab of the 9mm barrel to fit in. The 40 barrel just needs a little material removed from this tang/tab, to allow it to fit into the 9mm slide. All dimension indicate it would work fine and be just as accurate when shooting.

You would still need the 40 magazine, as the 40 cartridges don't fit in the 9mm mags.

Bob

 

[Dikinalaska]

Ok so I'm getting serious about this. I won't be able to do it til after the new year, holidays and such. But anyway, I know the issue had been beat to death talking about it the other way, but it was proven the smaller 9 casing is still able to be grabbed by the ejector because it's not that much smaller, but I don't remember hearing and I couldn't find out if the ejector was the same part, or just worked because the 9 isn't much smaller. If they're not the same will the larger casing put extra strain on it? I doubt it because of it being such a small difference, but I don't really know the mechanics of the ejector so someone that understands it a little better might have a better guess.

 

[Smitty357]

The ejector in the 40 and 9mm are the exact same part number on the full size and the C models. So IMO, i would expect it to also be the same with the Shield. I dont see why it would differ, if the others have never differed.

 

[Dikinalaska]

The ejector in the 40 and 9mm are the exact same part number on the full size and the C models. So IMO, i would expect it to also be the same with the Shield. I dont see why it would differ, if the others have never differed.

Exactly what I needed to know. Looks like a new project is in order

 

[robkarrob]

This is what needs to be reduced in size on the 40 barrel, so it will fit into the 9mm slide. I would only take off .010 from each side of the tang/tab. That should be enough to allow it to fit. You do want the side to side play to be similar to the play you find with the stock 9mm barrel in the 9mm slide.

All else should be fine, except for needing the 40 magazine.

Bob

 

[Dikinalaska]

Ok so thinking about this a little more, the 9 barrel fits in the 40 slide because the 9 tab deals are smaller. So would this leave wiggle room for the 9 barrel, and if so does it matter? I ask because, just exploring all options, would it be worth exploring the idea of widening the 9 slide itself to fit the 40 tabs? If so, would it have an effect on anything when using the 9 equipment? If it doesn't matter either way, which of the two between barrel and slide are softer material. Which would be easier to grind down?

 

[Dikinalaska]

Nevermind. After getting back home and looking at it, it wouldn't make sense to grind the slide. Mark that off as dumb question

 

[robkarrob]

You thought about and figured it out. You could grind the slide opening larger to get the 40 barrel to fit, but then you have messed your resale value and caused extra clearance for the stock 9mm barrel fit into the 9mm slide. Grinding the 40 barrel will only affect the value of the barrel, if any. Your only removing a very small amount, and only from the tang/tab.

No the extra barrel side to side play does not have any issues. I originally thought it might make the 9mm barrel less accurate due to more side to side play. This would only affect windage (left or right). Since both barrels lock into breach exactly the same (which controls elevation), there should be no problems in elevation. My shooting groupings were almost exactly the same with the 9mm barrel, as with the 40 barrel, within 3 inches at 15 yards. This is why I feel the swap od 40 barrel into 9mm slide is better, because you will not end up with the extra clearance, it should be the same or slightly closer.

I took some more measurements. The opening on my 40 slide is .433 wide. The 40 barrel tang is .425, which leaves .008 clearance. The 9mm barrel tang is .399, which should give .034 clearance, but it is only .025 clearance. This is less as the barrel can not move any more as it rests against the side of the slide and not the side of the tang/tab. Therefore the maximum side to side difference between the two barrels is .008 for the 40 and .025 for the 9mm, a difference of .017 (1/64 inch). This did not cause my 9mm grouping to disperse any more than with the 40 barrel.

Bob

 

[Dikinalaska]

You thought about and figured it out. You could grind the slide opening larger to get the 40 barrel to fit, but then you have messed your resale value and caused extra clearance for the stock 9mm barrel fit into the 9mm slide. Grinding the 40 barrel will only affect the value of the barrel, if any. Your only removing a very small amount, and only from the tang/tab.

No the extra barrel side to side play does not have any issues. I originally thought it might make the 9mm barrel less accurate due to more side to side play. This would only affect windage (left or right). Since both barrels lock into breach exactly the same (which controls elevation), there should be no problems in elevation. My shooting groupings were almost exactly the same with the 9mm barrel, as with the 40 barrel, within 3 inches at 15 yards. This is why I feel the swap od 40 barrel into 9mm slide is better, because you will not end up with the extra clearance, it should be the same or slightly closer.


Bob

Ya this Is what was going through my mind, just took a roundabout way of getting there. I was thinking of widening the slide to make the 40 tight, but wasn't getting the big picture. You're right going with grinding the 40 barrel will mean both barrels fit snug into the 9 slide and a better outcome overall.

 

[bigned]

Ho Ho Ho Santa sent me my 9mm barrel and 2 9mm extended mags, it came in the mail, at 5:00 last delivery for today. There is a Santa, I must have been a good boy. Yes it fits like a glove and works great in my 40 Shield.Now I got 2 guns for the price of 1, thanks all for all the input on this subject. Merry Christmas to all and be safe out there, Remember watch out for the other guy. Ned PA.

 

[Smitty357]

Ho Ho Ho Santa sent me my 9mm barrel and 2 9mm extended mags, it came in the mail, at 5:00 today there is a Santa, I must have been a good boy.

Merry Christmas to you and your family, glad to see he still delivers to us older folk, haha.

And welcome to the Converted Shield Club.

 

[Dikinalaska]

Ok so since I was ignorant and got the 9 first since I didn't know about the conversion, I decided to rectify it. Was browsing and my big-name gs had a .40 on the wall. I was a bit tight on funds from the holidays, so I just threw it on layaway til I recoup a little. So I'll have both size barrels and mags. I'm still going to get another 9 and .40 barrel because the original 9 is the girlfriends. It was the longest way of going about it, but now I guess we'll have 4 guns for the price of 2!

 

[Smitty357]

Ok so since I was ignorant and got the 9 first since I didn't know about the conversion, I decided to rectify it. Was browsing and my big-name gs had a .40 on the wall. I was a bit tight on funds from the holidays, so I just threw it on layaway til I recoup a little. So I'll have both size barrels and mags. I'm still going to get another 9 and .40 barrel because the original 9 is the girlfriends. It was the longest way of going about it, but now I guess we'll have 4 guns for the price of 2!

Kinda what I did to start with. Except i just bought both the 9mm and the .40 on the same day since they were both staring me in the face. After testing the 9mm barrel and mag in the .40 for a few months, i decided id buy a designated 9mm barrel and mag for my .40. This way I was able to give my original 9mm Shield to my ole lady for her EDC. And thus, allows me to be able to bring the .40 and designated 9mm barrel to the range with me.

I guess i kinda have a .40 and 2 9mm's in a sense, lol. But it all works out and I dont think any of us Shield owners can complain about how easy s&w made this conversion.

 

[robkarrob]

Those of us that bought the Shield 40 thought we had the best of both worlds. With just swapping out the 40 barrel with the 9mm barrel, we would then also have a 9mm Shield. Since I purchased the 9mm barrel from Guns and Gear, I have found that those with the 9mm Shields can buy a 40 barrel, and also have the Shield 40.

The only problem with the 9 to 40 swap is that a very small amount of material (.010 inch per side) has to be removed from the top rear tab on the 40 barrel. The side of the tab is only 1/8 inch wide by 3/16 inch high. It would be easy to remove this material with any type of grinder. I would use a 6 inch or larger bench grinder, using the side of the wheel to grind the .010 off. Very easy and fast, as .010 is a very small amount. It could also be done with a hand grinder or dremel. The 40 barrel will then drop into the 9mm slide. Then all that's needed is a 40 magazine.

Bob

 

[seattle911]

I can't take all the credit for it. I'll just take credit for giving video proof, lol.

As for Guns and Gear, i swear someone else mentioned that in another post somewhere on here. Maybe it wasnt directly stated towards the Shield, but im sure i seen it somewhere. So I called them and asked if they had 9mm barrels and mags. Lucky me, they had some so I went with it from there.

I'll gladly take that sales commission from them though. After all i did show proof it would work, and I did post pics of my new barrel and mag, lol.

Something told me I was starting an epidemic when I posted that original video back in September.

You saved me more than $300 buying another Shield (instead spending just $75 plus shipping), so I feel like I owe you a commission

 

[Smitty357]

You saved me more than $300 buying another Shield (instead spending just $75 plus shipping), so I feel like I owe you a commission

Good deal man, glad I could help you out.

Maybe I should go into promotional business for their company. I'll just go around promoting their products and showing what u can do with them. Sounds like an easy job for me lol.

 

[XxLaloCuraxX]

So has anyone tried the 9mm to 40 cal swap yet? I'm willing to give it a try but having a hard time trying to find the .40 cal barrel and mag.

 

[bobnieder]

No, not the 9 to .40 conversion. Just another .40 to 9mm conversion. I added a 9mm 4.25" barrel and mags to my Full Size M&P last August, and tomorrow I pick up a .40 Shield, which has a 9mm 3.125" barrel and an 8 round 9mm ext mag waiting for it in my safe (thank you, Smitty & Bob, and Judith Szczygiel of Guns and Gear). If the weather clears up, I'll take them out Sunday to run some .40 and 9mm ammo through the Shield, and check the sight alignment and see how she shoots!

 

[LiveorDie]

Just spoke to Chris at Guns and Gear. He said he has ordered Shield 40 barrels. He said he does not know when he will get them, as his supply of barrels from S&W has slowed down. He said he is currently out of the 9mm barrels. He now has both the 9mm and 40 barrels on order and is waiting on S&W to ship them.

 

[DonB]

You can not convert a 9 to a 40. The 40 cartridge will not fit the breech face of the 9mm slide.

Don