When I last attempted to get my AR,16", 1 in 9" twist AR to shoot and cycle with 55 gr LEE over 10 gr of 2400 I could not get it to cycle even with a cut down recoil spring and a lightened buffer. I'm planning to build a designated AR15 for this cast load only. I want to use a 20" 1 IN 12" twist; preferably non-chrome lined barrel. I've found Green Mountain Barrels sells a 1 in 12" chrome line barrel but I prefer a regular steel barrel and not even stainless steel. Does anyone know of a source of original 20", 1 in 12" twist new M-16 barrels.
Also I would like info on what length gas system would work better on this project; if a reduced poundage recoil spring and buffer are available and what size gas port is needed. I understand if I use an adjustable gas port that I may be able to also shoot standard jacketed 55 gr rounds but that is a secondary need and would not be pursued if not readily possible using 10 gr of 2400 and 55 gr cast bullets. Thanks in advance for any suggestions.
Because I said so!