What third hole on an ar15? Home defense, distance shooting, long and short-barreled rifles are all possible with a single AR-15, which is why it’s one of the most popular semi-automatic rifles available today. AR-15 creates not a hole but a ‘cavity’ in body, St. Luke’s surgeon says of rifle’s devastating power What I do is complete the further milling and drill, what is known as, the "third hole". Someone took an ATF Guy patch and placed it behind their machine gun NFA lower. Clamp in mill, 1/2"-3/4" bit and chop away. The hole being discussed is located forward of the retaining pin, just at the beginning of the forward assist serrations. FFL/SOT Chuck Norris has to maintain a concealed weapon license in all … What's True. The fire control group is one such difference. An M-16 has a third hole in the side of the receiver, right above the safety selector. The AR-15 platform gets a lot of attention and for good reason, it is one of the most reliable and versatile firearms ever created. This is rather funny. The jig … The drill hole is reinforced with a steel drill bushing to prevent wear and be able to use the jig over and over without any issues with tolerance. ArmaLite sold the patent and trademarks to Colt's Manufacturing Company in 1959. The M-16 Third Hole Drilling Jig is made for properly aligning and drilling the third hole for a full auto sear in an AR-15 style lower receiver. A flash hider is threaded onto the end of the 5/8×32 TPI muzzle. To accomplish this I use a proprietary jig to mill out the FCP to fit the M16 FCG and another jig to drill the third hole for the M16 auto sear. An AR does not have this hole. Here's mine: Last edited by 99HMC4; 03-25-12 at 00:08. #24 to #21 - dogscar . Once that is done I then install the M16 FCG with auto-sear into the lower receiver. If you buy a drop-in auto -sear that was manufactured after November 1st, 1981. it is by itself classified a machinegun , and must be serial numbered and registered with B.A.T.F. Get a auto sear hole jig for $35.00. Back to the content 'circumstantial dirtier Whale' Hide. This is a mil-spec M4-style AR-15 that comes with a 16 inch M4-profile barrel with a 1:8 twist rate. as such. An AR-15 style rifle is a lightweight semi-automatic rifle based on the ArmaLite AR-15 design, which is itself a scaled-down derivative of Eugene Stoner's AR-10 design. Tags: atf, batfe, Morale Patch, third pin hole . Thumbnails: The drop-in auto-sear was designed in the mid 1970's for the sole purpose of converting the AR-15 to fire full-autD (select fire]. An M-16 and an AR-15 share a common outward appearance, but the internals are quite different. This is where the autosear is. For those not familiar with full auto AR-15/M-16, the ATF Guy is peeking through the third pin hole for the auto sear. The lower and upper receivers are built out of forged 7075 aircraft grade aluminum. The hole shown in the poster could plausibly represent the diameter of the highly destructive temporary cavity left in a person's body by a high-velocity AR-15 round. Reply +10 [-] Third pin hole that allows full-auto trigger and safety group #22 to #21 - cotn . Reply-2 [-] The third hole you put in someone. The most noticeable difference is that the civilian AR15 lower receiver does not have the third trigger pin hole for the auto sear above the safety selector. After Colt's patents expired in 1977, Colt retained the trademark and is the exclusive owner of the "AR-15" designation. It's VERY strait forward. Engrave lower. The trigger pocket is also typically milled to different dimensions to prevent the acceptance of an auto-sear as well. The third hole in question isn't the retaining pin hole, nor does it have anything to do with LMT's modified carrier.