Not odd at all...
The small end of the spring slips over a small ledge on the guide rod to keep it in place so it has a smaller diameter. If you reverse it the end of the small coil will bind up on the guide rod and impair the slide movement to the rear, especially if you have a full length guide rod. It won't let it compress in recoil properly.
BJG
The small end of the spring slips over a small ledge on the guide rod to keep it in place so it has a smaller diameter. If you reverse it the end of the small coil will bind up on the guide rod and impair the slide movement to the rear, especially if you have a full length guide rod. It won't let it compress in recoil properly.
BJG