Machining a charging handle

[mblount]

What CNC machine would be the best to machine these AR 15 charging handles? Hopefully you wouldnt need a real expensive milling machine.


Charging Handle Machined from 7075 T6 Billet Aluminum

[foam27]

What kind of tolerance do you require?

[mblount]

What kind of tolerance do you require?

It's got to be pretty tight on tolerance because it is one the main component's of a Rifle.

[txcncman]

What do you consider "real expensive milling machine"?

[mblount]

What do you consider "real expensive milling machine"?

The Haas I looked up was $ 65,000. At a gross profit of maybe $ 30 I would have to make a pot load .

[foam27]

Just get a chinese mill and convert it with ball screws.

Or, skip it and buy my freshly converted one. G704.

[Caprirs]

"Best" depends on about a zillion factors.

- How many do you have to make?
- What is your budget?
- How capable are you at doing the service and maintenance on the machine?
- What are the tolerances on the part?
- How much room do you have for a machine?

The charging handles I've seen are all cast (cheap). From memory, the piece would need to start with a chunk about 3/4" x 3" x 8". In 7075, that will be about ~$20 each in material cost. Assuming a dialed in process, well designed fixturing, and no scrap, you might get 3 complete parts per hour on 3 axis vertical. At a shop rate of $50/hr, you'll have about ~$35 into each one. Still have to make the little release/catch doohickey, get everything anodized, assemble with pins and spring, and package.

With the above numbers, you can pay yourself about $15/hour gross. The rest of the shop rate goes to machine payment, coolant, $ervice/maintenance/repair calls, electric bills, measuring tools, repairing your air compressor, taxes, tool bits, tool holders, fixtures, in$urance, etc.