Originally Posted By: OKBrentI'm with wishbone. Sinclair make a top notch guide and they are caliber specific. They all come now with a built in solvent port. They will seal off the chamber 100%. I'm sure you will like them. Brent
Ditto. All Sinclairs come with a port now. I've been using them for years. Not familiar with all the others mentioned here, but I do remember reading some customer reviews on the Possom Hollow units that said the front end piece has a tendency to snap off in your chamber.