WATCH LIVE: Biden speaks on gun control at Gun Sense University conference

Correction: This headline has been updated to remove an incorrect location for Biden's speech — he is speaking in Washington, D.C. We regret the error. ATLANTA (AP) — Groups pushing tighter gun laws have been building political muscle through multiple elections, boosted by the outcry following mass shootings at schools and other public places, to say nothing of the nation's daily gun violence. The event is scheduled to begin at 1:30 p.m. ET. Watch in the player above. Now, gun …