The Haenel 33 used a special 8 shot magazine. Haenel 12 Shot Magazine, 4.4 mm, fits the models 33Jr, 49, 49a, 310, 400, 410, 510, 570, 580, LP55R, Anschutz 275, etc. It can be made to fit the model 33 by cutting a second notch in it for the latch to connect to at the correct depth. Install it all the way past the original notch, apply presure to keep it all the way in, then mark it against the latch. Then file a second notch at the mark similar to the picture.