Home Technology How To Make An 80% Drop (drill / mill)

How To Make An 80% Drop (drill / mill)

How To Make An 80% Drop (drill / mill)

Ready to build your own rifle or AR-15 pistol from scratch? This tutorial will show you how to reduce it by 80% using the Elite Builder 80% and a simple drill or mini milling machine. This ratio and these ranks work with the AR-15 (5.56, .223, 300 BLK) and AR9 (9mm) which are 80% lower. We use this fake receiver with “FIRE / SAFE” engraving. Before we begin, we also need hand tools.

Vehicle checklist

Drill or milling machine

Working vice

Canned air or bushes

Aluminum cutting fluid

Protection for the ears

Eye protection


Digital caliper

Drill stop collar

It is recommended that you use a minimum of a 4 inch vise to stabilize your work pieces. Coolant is essential if you want the drill bit to stay cool and sharp when machining aluminum. Brushed or compressed air helps protect the work area from dirt and aluminum. The drill or milling machine comes with a depth stop and stopper, but you can always double it with a digital caliper and stop collar. Both help to properly separate the receiver at the end of the end mill.

4 steps to follow

Cut the fire crack

Cut the ground drain socket

Drill a hole in the hammer pin

Drill a hole in the trigger pin

Drill a hole in the locking lever

Uses 80% lower jigs forging standard. Fortunately, this is one of the most basic gauges in an almost universal design, and these machining procedures include the AR-15 (5.56, .223, 300 BLK, 6.5 Grendel), AR9 (9mm), and LR. -308 (6.5 Creedmoor, .308 Win) 80% of receiver.

Let’s get started.

Adjust the bottom of the instrument

The two polished steel pins in the jig plate align with the swivel and tapping holes on the front and rear of the receiver. Place the receiver on the plate and align the pins. Align the second plate, then sew the assembly.

Install the template holder

The template holder holds the template plate for cutting and drilling. Insert the handle into the bracket and receiver. Align the large holes on both sides of the handle with the screw holes drilled into the top of each side-plate. Tighten the retainer to the fixture using the provided large Allen key and hex screw.

Warning: do not twist! The template holder only requires hand tightening and a 1/4 turn. If you twist the screw, the gauge will bend.

Install the pilot whole template

The pilot whole template is the only template with several holes. Install with a hexagonal bolt with a small countersunk hole and an Allen key. Do not over tighten these countersunk screws. They can be torn off easily. When the complete setting tool is ready, the work piece can be clamped in a vice. Again, don’t put too much pressure on the instrument. If you apply too much pressure, the plate will break. Tighten the vice just enough that the tool does not slip or move during operation.

Adjust the 3/8 “drill bit

Before cutting the lock to make room for the set of parts, use the 3/8 “drill bit from the kit to drill a pilot hole that will remove most of the aluminum from the lock and replace it. This is done to provide an entry point. Milling a bit while using it.

As the pilot whole template shows, drill 2.00 inch from the plate face. Adjust the drill bit stop to fit your milling machine or drill. If you are a new mechanic or are using a simple drill, keep the collar on and the caliper will help you adjust the drill depth.

Drill a pilot hole

After the drill bits are installed and the machine is ready, drill holes into each hole in the template and pilot holes in the receiver. Take your time and delve into the details step by step. Use plenty of coolant to clean the socket and any aluminum residue, and remove the drill bit from the work piece occasionally. Drill 2.00 inch from the face of the template until all 6 pilot holes is left. After creating all the remotes, you can: Delete the template. Replace with the next template, which is the first template to cut out. It is labeled “3/8 EM1.375 SO DEEP”.

Cut a 1.375 inch deep socket (3/8 inch short end milling cutter)

Remove the drill bit from the machine. Replace with 3/8 “short end milling cutter. The plate indicates to cut 1.375” from the plate surface. Calipers and stoppers help set up the mill and machine to prevent the plunge from getting too deep.

Before processing, please read the following information.

Using templates for cutting

The detach pattern guides the end milling cutter during receiver detachment. The shaft runs securely along the inner edge of the template, conforming to the shape of the main cavity of the parts kit, and acts as a side stop. Use plenty of coolant to lubricate both surfaces and prevent tool or template wear. Both can be reused in additional builds.


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