>>679
例えばSIG SAUERのP320向けPro-cut Slide Assemblyとかドロップインぽいのよ。
https://www.sigsauer.com/pub/media/catalog/product/cache/a3db8ca85b9f26a85c601248a3f4f74b/c/-/c-fde-front.jpg
https://www.sigsauer.com/compact-pro-cut-slide-assembly-p320f-fde.html
レビュー
https://www.gunsamerica.com/digest/sig-pro-cut-slide-7d-chess-move/
"The Sig Pro-Cut, for that $400, comes out of the box ready.The firing pin, back plate, night sights, everything.
"Drop in your barrel and recoil spring, put it on your frame, and you are ready to get some.
まあスライドに質量あった方が慣性力大きくて止まりづらいとは思うけれど