You cannot put an M4 extension on the existing barrel. The gas port and the hole for the index pin are drilled after the extension is installed. If you throw on a new extension the gas port will be out of alignment and will need to be plugged and a new hole drilled.
If it bothers you that much I"d just have a competent smith extend the feed ramps into the upper. Or you can take the DIY route with a dremel. Personally, I'd leave well enough alone, it will work fine as is. FYI the C8 doesn't have M4 cuts. Don't think the new C8A3 does either but I'd have to verify that.
If it bothers you that much I"d just have a competent smith extend the feed ramps into the upper. Or you can take the DIY route with a dremel. Personally, I'd leave well enough alone, it will work fine as is. FYI the C8 doesn't have M4 cuts. Don't think the new C8A3 does either but I'd have to verify that.




























Yeah, it won't index! OK, I'll run it as it is or add them to the lower if I get really ambitious. Thanks.






















