CNC Milling an AR-15 Receiver From Scratch Chapter 7: Magwell and Buffer Tube

[PoliticalSmackdown]

what mill are you using?

[kingjamez80]

@PoliticalSmackdown Sieg X3 with cncfusion conversion kit.

[silver760]

A truly commendable job,from experience of day in day out manual machining of alloy blocks into hydraulic valve blocks there were a number of ways you could have saved yourself a considerable amount of time and effort.I'm surprised you didnt have any trouble with your tooling picking up milling alloy dry,the best cutting fluid for alloy is kerosene or light oil for best finish and tool longevity.You certainly persevered on this job,well done!!

[kingjamez80]

@silver760 Thanks! I know that I could have done things better. This project was my first machining project ever, so I am very much a novice. I learned a lot though and would really love to one day learn from a mentor on the right way to do things. Right now the Internet is my mentor, and we all know that truth on the web isn't always so truthful.

[silver760]

@kingjamez80 I was careful as I didn't know ability level.I didn't want to teach another how to suck eggs or bash a novice who is learning. Having worked in the engineering industry and machining for a number of years sure teaches you the right and wrong way to do things.The management always want things out the door in the fastest time possible at the highest quality,you learn how to make such things in the quickest easiest way to top spec.The tricks of the trade are rarely written down though!

[drewdane40]

@9o3 A homebuilt lower doesn't need to be serialized or registered, but it may only be made for personal use, so it may never be sold (though I'm sure someone will argue that point.)

I am not a lawyer. Check your local laws. Your mileage may very. Offer void where prohibited. For entertainment purposes only. Keep out of the reach of children. Past performance is not a guarantee of future results. Do not leave children unattended. May cause drowsiness. Use caution when operating heavy machinery.

[kronenbitter85]

hello im looking in to getting a set up like this is there a way you can send me the link or give me the name and all the details i have every thing for the pc

[TheTNPFBI]

Would this be easier to do on an ar15 forging?

[kingjamez80]

@TheTNPFBI I wouldn't be able to make my aesthetic changes like the magwell, side contours, and angled buffer tube post with a forging. It would just look like a plain AR and that would be boring.

[TheTNPFBI]

@kingjamez80 I agree but I was asking more from a technical standpoint because I'm looking into doing this myself.

[kingjamez80]

@TheTNPFBI Ah.. I understand now. The magwell method that I used is very similar to how I'd do it on a standard AR15 forging. You need someway to hold the forging vertically (I made softjaws). The method I used is basically from the Ray-Vin guide.

[brokebiker19]

how much would you sell on of these for?

im very interested

[kingjamez80]

@brokebiker19 I don't have a manufacturing license so I can't sell these.

[9o3]

@kingjamez80 so you only need a manufacturing license to sell lowers but not to machine them for an ar build? What about the serializing and registration of it?

[marksrig]

You didn't need any cutting lube?

[kingjamez80]

@marksrig Nope, works just fine without it.

[NovaStar77]

Nice job!

[przemkula]

Really profi job!

I'm using the same set of software (except Alibre - mine is 2010 ;-) ).

Could you please explain how you have managed to reposition the material so accurate for 4-sided milling?

[kingjamez80]

@przemkula I have zeroed the mill against surfaces that I know the position of exactly according to my CAM software. If the side of the lower is exactly 0.7" (for example) from the centerline, then I zero against the side and then put an offset of 0.7".

[kingjamez80]

I did leave the spindle unlocked for about 1/2 this operation. I did some drilling before this op. Fortunately the cuts were light due to the long end mill.

[replicaprops]

Did you leave the spindle plunge unlocked? I did that one time and it caused the milling bit to walk down deeper than I intended to cut.