So the other day I'm shooting at the range and all of a sudden something seems very wrong. I'm trying to get a sight picture and can't. It's all very confusing until I realize my front sight is gone. So after hunting around for it in the grass and old empty cartridges at the firing line I find it.

Seems the roll pin fell out or was never there to begin with. I honestly can't say whether it ever had one or not, just took it for granted and never checked.

Had the gun about a year and it just happened yesterday, maybe 1000 rounds through it all told.

So my question is this, what is the correct length and diameter roll pin used to hold this in place? Once I get the new one I'm going to lock tite it in, hopefully that will fix it and never have this problem again.

All of the Novak front sights that I am familar with are installed in, and held in place by, a dovetail cut in the front of the slide. Rollpin??? I have no idea. Charles the Gunsmith.  

All of the Novak front sights that I am familar with are installed in, and held in place by, a dovetail cut in the front of the slide. Rollpin??? I have no idea. Charles the Gunsmith

It's got the dovetail cut. This is a Springfield Armory and came from the factory with the sights installed. There is a hole on the front sight itself and a corresponding hole in the slide. It does not fit tight into the slide, slides back and forth easily so I don't see why else a hole would be put there. Hmm, maybe I need to call Springfield on this. Here's a pic anyway of what I'm talking about. The discoloration around it is residue from where I tried lock-tighting it in place to finish the range session, didn't work too well.

Roll pin size for Novaks is 1/16"and they are usually tight, who knows if something went wrong when they drilled that one and it may be a little oversize. To tighten that dovetail up a bit secure the slide in a padded vise and take a 3/32" or 1/8" punch and locate the top dead center of the dovetail. Take a small ball peen hammer(4 oz. works great for this) and give the punch a rap(it doesn't need to be hard) just to roll the top edge of that dovetail over, try sliding the front sight in, if it's tight then go ahead and loc tite the dovetail and finish installing the sight. Set your roll pin, loc tite that as well and you should be good to go.  Hope this helps

I had almost the same issue (the roll pin never made it the whole way out of the sight) with my Springfield Armory Loaded model.  I would notice that the front sight would seem a little taller after shooting.  I observed the roll pin was literally walking itself out of the front sight.  

I added a little blue Loc-tite to the equation and its been good so far.  

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