From what I have found about mine, it does not hurt them to dry fire and many advocate it to smooth out the trigger quickly instead of polishing the internal surfaces. However, I decided it would be best to polish trigger by hand instead of wearing it in by dry firing. While everything I've read says it is OK to dry fire, I personally feel better using snap caps for constant dry fire practice and only dry fire mine occasionally. There is a S&W forum devoted to the Sigma and SD that may help too.

I polished the internals AND (still) use Snap Caps. I got immediate improvement via the polishing and slow, but continued, improvement via the Snap Caps.

I have had my S&W Sigma 9mm for about 4 months and I make it to the range about once every other week. I finally got brave enough to take the trigger mechanism apart, using a very well made Youtube video as reference. (I never would have got it reassembled without that video to use as a visual aid.)

Anyhow, I just took out the "pigtail" spring, and put it all back together. In the video, they take out the big outer trigger spring also; but I believe in taking things slowly, one at a time. ( I have seen and heard other peple say that taking out the big outer spring will cause the trigger to NOT RESET, this is obviously not a good idea)

Then I got some snapcaps and every day I spend about 10 - 15 minutes practicing in my hallway, so the snapcaps don't fly off everywhere. I practice holding the gun rock steady as I dry fire. The gun is definitely improving. The last time I went to the range I was hitting bullseyes repeatedly from 30 feet. I mean, almost dead center over and over; till I just got tired.

Taking out the "pig tail" spring made the trigger a little lighter and did not have any adverse effect on the gun's performance. It performed flawlessly; just like it always has. I've NEVER had a jam, a stovepipe, a misfeed, nothing in about 600 rounds of shooting. ( I have two other guns I take to the range also, so. These guns are extremely reliable if you clean them. I use Eezox to clean it and that also has helped to make it smoother.

I believe that this gun is now a very good weapon, I feel confident I can place a shot where I want it to go, at least out to 10 to 20 yards. And it just keeps getting better, or maybe it's just that I am getting better, probably both.

If you will just take the time to work with this gun, it will wear in and become a vey reliable, very accurate gun.

I really don't think it will hurt your pistol. Smith & Wesson practically copied that pistol from the Glock, enough so that they had to change some things to get out of a legal battle over patent rights. Anyway, I would say(just my opinion here) it is safe for dryfire.

I finally took the time to read the manual carefully and the Smith and Wesson Manual for this gun plainly states that is will not harm the gun to dry fire it.

I guess that is about as authoritative a source as you could want, the manufacturer's manual.

Still, since I have the Snap caps; I like to keep a Snap Cap in the chamber of all my handguns (two) because there is no way a Live round can be in there, or get in there accidentally. When you rack the slide, the snap cap flies out, it is just one more safety measure to alert me to the fact that, now there is a live round in this cocked gun.

You see, I had a whoops moment the other day, fortunately no-one was hurt, and not much damage was done (the bullet just happended to hit a 2x4 stud and only made a little hole in the wall, which I was able to fix easily. But it wakes you up to how you really need to ALWAYS check your gun for live rounds before you stick you finger on the trigger. What a dumbass!

Originally Posted by Tackdriver9mm

I finally took the time to read the manual carefully and the Smith and Wesson Manual for this gun plainly states that is will not harm the gun to dry fire it.

I guess that is about as authoritative a source as you could want, the manufacturer's manual.

Still, since I have the Snap caps; I like to keep a Snap Cap in the chamber of all my handguns (two) because there is no way a Live round can be in there, or get in there accidentally. When you rack the slide, the snap cap flies out, it is just one more safety measure to alert me to the fact that, now there is a live round in this cocked gun.

You see, I had a whoops moment the other day, fortunately no-one was hurt, and not much damage was done (the bullet just happended to hit a 2x4 stud and only made a little hole in the wall, which I was able to fix easily. But it wakes you up to how you really need to ALWAYS check your gun for live rounds before you stick you finger on the trigger. What a dumbass!

Well, the snap caps are OK for practice, but I hope you don't carry with them in your gun.

No, I am just keeping one in the chamber when I store it in the house. I mean, I've got 16 rounds after I rack a real bullet. And another 16 in the extra clip. If that doesn't do the job, One more isn't going to make much difference.

I am just keeping the snap cap in the chamber, in the house, so if I cock the gun, the snap cap will fly out and remind me of my previous foolish mistake.

I think I am going to stop practicing with the snap caps, the gun is wore in good enough, and I don't think I would have shot a hole in my wall if I had not been doing the dry fire practicing. I got confused, and had a live round instead of a snap cap, and bang, hole in the wall. Thank God I had high quality Hornady Extreme defense bullets in it, The honady bullet hit the 2x4 and mushroomed, and stopped. If it had been a FMJ, it might very wel have gone right through the wall and out the other side.

I have a little CO2 bb gun that also has a stiff trigger, and I am going to stick to practicing with BB's if I can't make it to the rifle range.

The only 2 reasons I even mentioned it is because (a) nobody knows who I am so my identity is unknown, and (b) to remind anyone who reads this that it can happen SO, SO easy. Don't get over confident, don't try to do 2 things at the same time, if your are handling your gun, focus on just that one thing.