*UPDATE* Adding MTS to Shield Plus Carry Comp

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*SEE MY REPLY FOR UPDATE*

Hey everyone!

My first post here, although I've been on various forums for many things throughout the years.

I've made up my mind about needing a manual external thumb safety as a first time carry person and I absolutely love my 13390 SPCC. Downside of course is that it does not have a TS.

That said, I know my options are to buy a separate shield plus frame with existing safety and swap (this is neither cost effective nor fun since I live in NJ and would require another purchase permit), but does anyone know if it's possible to add it to the existing frame with minor modification? I've watched this video and can't tell if the aftermarket TS will fit directly on the SPCC FCG and the only other requirement is to cut the frame.

[ame]https://www.youtube.com/watch?v=Z1wtpKg39_o[/ame]

Would appreciate any insight.
 
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Side note: this is all a moot point if you are looking to purchase a new gun since the SW model #14410 is the shield plus carry comp with a MTS.

*****

Alright, since no one seemingly has done this before, hopefully this update will answer the question.. which is a resounding no. At least not without frame modification.


I took the $ risk of ordering the manual thumb safety lever, spring and detent (links below) to try and see if adding this to be 13990 Shield Plus Carry Comp was possible.

1) The pieces do fit the sear housing (rear assembling housing). Meaning, you can easily add the manual safety lever onto the housing and there is already a port/groove in the housing to install the spring and detent. From my observation the sear housing likely is the same as other shield plus models. Install was a cinch.

2) Now here's the problem. The polymer lower frame is molded to accommodate the sear housing without the lever, so the inner diameter is naturally smaller. When installing the new thumb safety lever, it increases the width of the sear housing by 1mm or so on each side, which presents a problem because I am unwilling to machine the housing myself to get it to fit. My concern is if the milling/grinding is not completely flat, it will cause complications with the entire gun and i'm just not willing to do that.

So that's it, the end of the saga is that installing a manual thumb safety is certainly possible to a model 13990 shield plus carry comp, but it would take precise/flat machining (or someone with steady hands, a dremel and brass balls) to get the rear housing to fit with the additional width of lever. Goodluck to anyone who's scoured the internet for this information.

safetyS&W M&P Shield 1.0 M2.0 Plus Manual Thumb Safety Lever Frame 9mm 40S&W 30sc 2.0 | eBay

Safety detent spring Smith & Wesson M&P Safety Detent Spring: MGW

Safety detent Smith & Wesson M&P Safety Detent: MGW
 
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I respect your DIY attitude. I do all my own trigger work and repair/maintenance on my own firearms.

My question is on this one.. have you thought of contacting S&W and tell them what you’re trying to do? They may…either offer to send a new firing block or.. have you send it in for this mod, done correctly…

I have zero issue with a little filing and polishing of parts for better fit/function, but this one.. no thanks from me…

This is my personal opinion, and mine only. I’m a fan of MTS on Hammer fired, like my 2011s. I’m not a fan of it on striker fired.
 
I respect your DIY attitude. I do all my own trigger work and repair/maintenance on my own firearms.

My question is on this one.. have you thought of contacting S&W and tell them what you’re trying to do? They may…either offer to send a new firing block or.. have you send it in for this mod, done correctly…

I have zero issue with a little filing and polishing of parts for better fit/function, but this one.. no thanks from me…

This is my personal opinion, and mine only. I’m a fan of MTS on Hammer fired, like my 2011s. I’m not a fan of it on striker fired.

I haven't contacted SW directly but I've done enough research to see a few have already tried to do so with no success.

Understood on the safety vs no safety discussion. I am half and half on it, meaning I have small children and the extra peace of mind is worth it to have it on. I know everyone on the internet has their own strong opinion on it, but that's mine.
 
I don't recall seeing your original post else I would have mentioned the safety cutout.

A few models of poly framed M&Ps have cutouts in the frame to accommodate a thumb safety. The variants without the safety simply have small blocks to close the opening. Installing a safety simply requires the parts and removal of the blocks. Since nothing is permanently modified, reversal is just as easy.

The Shields and the Metal frames are different. The Shields have the safety recess formed in the polymer frame when manufactured. The non safety Shields do not. The metal safety frames are machined with the slots. The non safety Metal do not have the slots milled.

So converting a non-safety to a safety requires some "machining". This would clearly void any warranty. A bad goof up could ruin the regulated frame. Worse yet, you could be liable for any malfunction arising from your "modification".
 
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