Call for Ms. Tamara! Call for Ms. Tamara!
I'm sorry but I have to laugh. There's another thread in the handgun forum where an International member is asking for a Tamara who works for Glocks. Apparently dear ole Tammy is gaining international recognition.
twoblink: the above posts are correct as to the Taiwanese Type 68 rifle. It combines the lower of the M-16 with the upper of the AR-18 rifle. It's a gas operated system (as opposed to a gas impingment system of the M-16). On the M-16, gas travels through a gas tube that runs from the front sight post towards the upper receiver and from there, acts upon the bolt carrier and forces it back, unlocking the bolt from the barrel sleeve (the barrel of the M-16 does not have corresponding locking lugs machined into it but rather has a barrel sleeve that is inserted into it for that purpose). As the bolt carrier travels back, the bolt's extractor pulls the expended case from the chamber. The bolt carrier also pushes on the buffer, causing the buffer to compress the buffer spring into the buffer sleeve in the stock. As the bolt goes back, it forces the hammer back and the hammer engages the sear, locking it back. When the bolt carrier travels fully to the rear, the bolt passes the ejection port and the ejector forces the spent cartridge out of the receiver.
The buffer spring pushes the buffer forward. This in turn causes the bolt carrier forward along with the bolt. As the bolt moves forward, the feed ramp of the bolt engages the bullet at the top of the magazine, stripping it from the magazine and up along the bolt face where the rim slips beneath the extractor. Simultaneously, the forward motion forces it towards the chamber. As the bolt carrier continues forward under the influence of the buffer, the bolt is rotated such that the locking lugs interlock with the corresponding locking lugs of the chamber.
Now, the Type 68 varies in that instead of the M-16 gas tube with the gas travelling down a long gas tube before acting upon the bolt carrier, the gas in the Type 68 travels only a short distance and acts directly upon a piston. Said piston/operating rod runs the length of the barrel and into the upper receiver. It travels back and impacts against the bolt carrier which functions much like the M-16 bolt carrier. Same with reloading and locking up. As the bolt carrier moves forward, it forces the piston/operating rod forward back into its position of rest near the gas port.
I'm not sure if the Type 68 actually has fewer parts than the M-16, but it certainly has
more moving parts than the M-16. That the M-16 has
fewer parts makes it conducive for accuracy. Fewer parts, better harmonics and less to disrupt the harmonics of the rifle.
BTW, you'll have to wait for Tamara to drop in if you want a better explanation.