Do I havet to chamber a round with the T-charging handle when reloading my M4?
The short answer is probably, "yes." You write reloading
, indicating an operation after firing. If you have emptied the magazine, the bolt of a properly functioning M4/M16/AR15 locks open. In this case, you may insert a loaded magazine and then either
press the tab on the bolt hold-open catch, OR pull back on the charging handle.
Pressing the catch is probably better, as it is the quicker maneuver, and it does not expose the charging handle, however briefly, to damage. Notice that the charging handle is not spring loaded itself, so pulling it rearward with the bolt locked open leaves it loose and more subject to side-to-side play.
Of course, if you have NOT fired the rifle after the final round from the mag was chambered, the bolt would be closed, and, no, you'd not have to close the bolt by either method.
If you contemplate acquisition of such an arm, you'd do well to purchase some sort of reference or training manual. This is practically as much part of the system as additional magazines, sling, and cleaning gear. The US military field manual is invaluable in learning the operation, disassembly/reassembly, and maintenance of the rifle. You simply disregard the parts dealing with the full auto or burst fire features. If you are buying a Colt brand item, their factory manual is quite good.