My M&P15T is a couple of years old but I want to take the screw out factory front pivot pin and replace it with a spring loaded pin. What size do I need? I only see .250" for sale but I don't know if that is the correct size. Help anyone?? Thanks guys.

I don't know for sure as I have never changed out a front pivot pin, but AR15's parts are fairly standardized for the 5.56/.223 versions anyways, so I would think that would work. I haven't seen the screw type in person but it should be approximately the same diameter as the push pin type. Just hate seeing questions sit without someone trying to answer. If in doubt call S&W. You might even check out the Brownells website, they have some AR15 smithing videos there.

Thanks Tbat, that seems the way to go, I'll check with Brownells.