Internal Lock Removal

greatzippy · Feb 4, 2009

AS WITH ALL TECH TIPS YOU FIND ONLINE USE AT YOUR OWN RISK. YOU AND YOU ALONE ARE RESPONSIBLE IF YOU BUGGER IT UP

I have an internal lock on my 40FS and it's always bugged me. The M&P40 was my fist gun and I got it before I realized it can with or without it. I mainly picked it cause it was the one that felt the best in my hand. I just hate it being there, I'm sure S&W made it so it "shouldn't" lock on you when you need your firearm most but that fact that it could has always been in the back of my mind.

I now it's been mentioned that the internal lock can be removed (granted I found that out after I just did it) but I didn't see any instructions on how. Since I actually managed to remember to take some pics before I put it back together .........

First you need to remove the rear roll pin with a punch. It really help if you use a vise to hold the frame while doing this.

Then you need to pull up on the rear sear block to remove it from the frame. Once you get it moving you'll want to pull the trigger to ease the tension on the trigger bar.

On the side of the block the key insets into you'll see a round "washer" holding the internal lock pin in place. This will pop out allowing the pin to fall out.

Turn the block over and look for the other side of the lock pin, this is where you need to place your punch. Place the block in a vise, it takes a bit of force to get the washer to pop out but it will. Take it nice and slow, when the washer does pop out the spring under it will want to take off or cause the washer to take flight like it did in my case. So you may want to place a small bag over it to catch it.

Once that's done hopefully you still have all the parts

Not sure if you need to replace the washer or not but I did. I just placed the washer over the hole and used the vise to press it back in. If you replace the washer, when you reassemble if you are having trouble getting the block back in you may not have pushed the washer in enough .... a few taps with a small hammer did the trick for me.

Replace the roll pin and your done.

One more thing .... while your working take care not to let the pin holding the sear or sear disconnect to come out.

jasonuscg · Jan 30, 2011

mig1nc' post='286070' date='Jan 30 2011 said:
DOH! I was google-slapped!

Good to know, honestly those are cheap enough that I would just buy the new unit.

I had no hostile intent in that post.

AFAIK Brownell's only has the one sear housing block.

SSS does have the holy grail without both locks for $30, it's on page two of this link.

http://www.speedshooterspecialties.com/cat...arts&cnt=12

Here is the direct link.

http://www.speedshooterspecialties.com/cat...%20mag%20safety

The Fish · Feb 8, 2011

Just removed my Internal Lock and then tried to install the Apex Ram Kit.

The RAM arm would not go all the way thru.

Discovered the reason was that I had created a tiny burr at the beginning of the hole when punching out the lock from the right side.

Suggestion;Using a 1/8 in. punch make sure you are centered on the lock assembly so that you don't hit the body of the sear block right around the hole and create a burr in the first place.

If you do create a burr,use a 1/8 in. drill bit to open up the hole and remove the burr.

This technique was OK'd by Apex and worked for me.

doubletap13 · Mar 7, 2011

Those of you who did remove your lock, I assume you have since test-fired and confirmed that what you did worked?

SMMAssociates · Mar 7, 2011

doubletap:

Over the month since The Fish posted the last message in the thread, you'd think somebody would have tried it

....

However, since I don't really know how the Hilary Lock works (I'm guessing it forces the sear to stay engaged regardless of trigger action), your post is prudent.

I have the feeling that removing it does nothing special except to remove whatever block is applied to the sear.

Anybody know? I'm not about to buy a gun with it, even though it's fairly easy to remove. Besides, between the wife and the VISA card, it'll be a while....

Regards,

waktasz · Mar 8, 2011

I can't speak for everyone else, but I removed the lock from the replacement sear block I got from Brownells before I put it in my M&P Pro and have probably shot 800-1000 rounds since then. No issues.

Took the mag safety out at that point too as a matter of fact.

doubletap13 · Mar 8, 2011

waktasz' post='291816' date='Mar 7 2011 said:
I can't speak for everyone else, but I removed the lock from the replacement sear block I got from Brownells before I put it in my M&P Pro and have probably shot 800-1000 rounds since then. No issues.

Took the mag safety out at that point too as a matter of fact.

Good to know.

Thanks

Tornado_Racing · Mar 20, 2011

I have removed the mag safety & internal lock with no issues out of my pistol. You guys here were very helpfull with part location and tips for the removal/install. I've now installed a full DCEAK, RAM (had to remove the internal lock), and removed the mag safety all with help from this forum.

The DCEAK and RAM are night-n-day over the stock parts so thanks for the help guys.

Tony Moffre

Tornado_Racing

RockBottom · Mar 20, 2011

So, does anyone know of someone every having a problem with the internal lock locking unintentionally?

TOF · Mar 23, 2011

The locks and guns act the same. They only fire or lock themselves on the third moon in the month of July. Stay out of that time zone and you should be aok.

PC Geek Shooter · Jun 30, 2011

Thanks so much for this.

I just installed the Apex FSS and Trigger, but I got the newer Sear Housing Block with the bigger sear plunger and spring. It had the Internal Lock. I could not get the new sear housing in my gun. The washer kept grabbing on that plastic or aluminum plug. So I took out the plug and the sear went in within 10 seconds.

It was about 5 hours after I should of went to bed and I finally gave up last night. So tonight I took out that stupid internal lock and I got the sear in within a minute.

Thanks again.

Lefty Gunner · Jul 5, 2011

Quick hint for the Frame Key Plug......

Carefully increase the diameter of the end of the plug by hitting the external surface with a center punch placed exactly in the middle of the diameter. Start easy and test fit. When you reach the right amount of upset the plug press fits into the frame and does not get lost the 3 or 4 times it usually does during reassembly!

The dimple in the center of the plug looks OK when assembled.

KRWeiss · Jul 5, 2011

Lefty Gunner said:
Quick hint for the Frame Key Plug...

One dot of silicone sealant worked fine for me, YMMV.

waktasz · Jul 5, 2011

I lost that thing the first time I took my gun apart. I'm pretty sure I don't miss it.

jackrabbit000 · Dec 19, 2015

Thanks for starting this thread and taking the time to post the pics. I just received my new upgraded sear housing block from Brownell's with the 1/8" sear spring and plunger. Going to remove the internal lock and mag safety and rebuild it with the parts from my 5" Pro Series sear housing block.

Update >> put the sear housing block in a vise and only the slightest tap with a punch and the internal lock, spring and washer popped off. So simple to do.

Internal Lock Removal

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