What brand of primer are you using? Light strikes basically trace back to either primers seated too high, or primer cups too hard. Edges run a 19lb mainspring as stock (most 1911's run 23lbs) which may have some trouble igniting harder primers.
Problem can also be too short, 1911/2011s for reliable use need a longer OAL, had trouble with my Sentry and solved them with a 1.160 OAL. Not saying is the problem but you will have less problems overall.
When I was using a single stage press and hand priming all my ammo, I would have about 5% light strikes. Since switching to a Dillon 550, the problem has disappeared. Over 12,000 rounds without a light primer strike.
Unless you are using really hard/crappy primers, your problem is almost certainly do to not seating the primers deep enough. And I agree that overall length has nothing to do with light strikes.
High primers will cause light strikes. Most load 1.185 oal. I load mine to 1.20. Oal won't cause light strikes. Is this a new gun ? I would call STI. You might also check the firing pin and spring. I have read that the edge comes with a 15 lb mainspring. I am running a 18 lb spring in mine with no problems.
Thank you for all the great suggestions. I'm using CCI small pistol primers, Dillon 550 press and I have a Wolfe progressive 16.5# recoil & firing pin spring. Primers are flush, but I will work with the OAL.
Is your firing pin tunnel clean? Firing pin spring good? I agree that OAL won't help at all with the light strikes. I load mine to 1.125 and have no issues. I would check those 2 areas and if they are good go, go to a heavier mainspring, if they still persist contact STI or look at using Winchester or federal primers. Don't CCI primers have a reputation for being hard? primers should be a little below flush also
For the Edge, I load mine 1.165 to 1.175 OAL. You might try a new firing pin and power spring. They aren't very expensive. You didn't happen to have a trigger job done did you? The main spring might be too light which would cause your problem. Also high primers. Check your Dillon and see if it isn't leaving high primers. I load mine with an RCBS Rock Chucker as I am retired and have lots of time. I had a progressive press and had problems, so I went back to the regular and SAFE way. Good luck. I hope we all have contributed something for you to try. WG
For that setup most run 1.18 OAL which isnt causing light strikes. For that I would add a Dawson extended firing pin http://www.shootersconnectionstore.com/Dawson-Hyper-Drive-Extended-Firing-Pin-P708.aspx and a 17 pound ISMI main spring. If you want to go even farther add a 19 pound main spring but mine sets off everything with the dawson and the 17 pound. For recoil spring try a std 12.5-14 pound ISMI is my preferred and see how it tracks compared to your 16.5 as you may have dip with the 16.5 when it closes as the vast majority run the 12.5-14 pound
Make sure you are seating your primers deep enough, I seat them deep to where there are slight marks on them.
The factory STI mainspring is 15#, which is what I use on my builds.
I only us Federal primers, so no experience with CCI
My 2011's like OAL's from 1.180" to 1.200"
On my 2011's that I built, I use the Dawson extended FP.
12.5# is what I use for recoil springs.
Federal are the easiest to set off of all the CCI is one of the harder with the Tula being even harder than CCI. With CCI a 17 is the way to go with the Dawson and is what I run in mine and the difference in trigger between 15-17 main spring is so minimal it's worth the reliability. A 19 could be used and it will haze zero issues with any primer but not really needed