Low Speed....... I know what the forum flock are saying but believe me, it's a bog standard common repair that every real Armourer has been doing at the factories, as apprentices and out in the army world for the past 100 years. It's a knuckle patch and the butt would split down the grain there as BAR has mentioned. We used to do these day in, day out. You can tell that it's been done by an Armourer by a); the two strengthening dowels (made from tapered oak usually), glued and knocked in tightly and b); the fact that it is well done. New butts came like that too and with heel, toe and cheek patches to boot