Gorilla normally works. Most epoxy will also work.
I used 5200 for my Blackout and got a ton of swings after the split.^^^^^^^^
BTW, Dont use the White on a cracked endcap................Umps bug you about it
Also will this void warranty?
Batting practice to get it the rest of the way out is my suggestion. This does not void the warranty. My Dba that blew last year i had to 5200 the cap back in and i got it warrantied.