Originally Posted by
Ballistics in Scotland
Ahhhh!!!! But things are worth doing for a rifle like that, which aren't for something which is going to be pretty rough anyway.
When you only have an old crack, rather than separate pieces, getting dirt and debris out is important. You can get superglue into just about any crack, but it has virtually no gap-filling ability as epoxy does, and you don't get time to correct mistakes. As well as various stiff plastic sheets, unwaxed dental floss can be useful for cleaning out the crack.
I'd always use the standard epoxies, taking a couple of hours or more to set, rather than the five-minute varieties. The extra strength and heat resistance don't matter in this context, but I've lost count of the times I've found the phrase "five minute job" ringing hollow.