Making Copper Bullet Jackets: Machining Punching & Drawing Dies! Part 2

Hi folks, welcome to another episode of NYC CNC. I've got my new lathe now and I've really been enjoying using it. I was really happy with how the project turned out on making the custom stripper for the Whitney punch and I've been sitting here thinking about what's the next good fun project to do and something I haven't talked a lot about is that despite being a NYC CNC name I actually grew up in the Midwest and have been a lifelong shooter. It's something I've gotten back into a lot since I left New York City and one of the things I've always been fascinated with is bullet technology and bullet shapes and I started researching bullet making and so one of the things that I've started to explore is making my own bullets and part of that involves making your own copper jackets just like you see right here. So I wanted to do is show you the set of test dies that I made these are just aluminum show you how they work and then have this be a kickoff video for a series on I'm really excited for this project it'll be a great project for the new lathe and it will involve a lot of skill sets it'll be tool and die level precision if you will in terms of both cutting and measuring it will be exploring worlds of blanking and cupping and drawing which frankly isn't something I've done a ton of and there'll be another aspect of polishing or lapping to get not only tolerances but finish quality and you know maybe eventually even heat treating so let's dig in so the goal is to end up with a cup like you see right here but you start with a piece of copper strip you can see here I've got one where I've actually already cut the blank out of it which is this one here this is a 950 thou diameter 30 thou thick piece of copper and then you use a series of dies to draw it into this these are my first set of dies I just bang these out quickly as a proof of concept to see if I could do it they're aluminum which is definitely not the material you want to use but they prove the point for me which is I think this is something I can tackle the way these work is this is a blanking punch this piece slides through the slot here and then this punch comes in and snaps down and blanks out a strip as you can see me doing right here and just a home shop press and then rest it inside of this and just using a arbor press actually will work fine you center it over it you push it down and you turn this piece here then you set that piece inside of this bushing which then goes on top of this draw die and then all these next ones fit inside of this arbor if you will and then you use this punch and you push this down piston down through with the hydraulic press or an arbor press and that gives you this shape and so on now it ends up that this is a bigger piece that I'm starting with so that was good though that's what I wanted to learn we can start with a much smaller blank and one of the things I want to show is and we'll hop over right now here is let's take a look at the CAD model for the next design this is the first stage and this is actually a combination die that does two things the light green piece here will I'm going to make in two pieces the top half will have a groove machined in it that will guide the strip through it and then it will punch out half inch diameter blanks with this the OD of this yellow piece here acting as the punch but then what's different is that this is actually going to serve as a double function which is that after the die blanks out the half inch blank the punch here will turn into a die and this purple piece in here will serve as the punch if you will and this will continue down through it will actually perform the first draw right away all in one motion so I've got the CAD model designed the next step is to go ahead and start making some chips to do that I had to buy some material and I did some research I was originally thinking I was going to use 4140 it's such a great material for heat treating but then I did a little bit more research online and I came across 1144 I personally haven't worked with it before but it was I was told it machines really well and has a really good hardness rating in its annealed state and sure enough grabbing the machinist handbook and taking a look it's got a higher sulfur content that makes the better machining material and it's got a little bit higher manganese which is why it's a good hardness rating so let me know how much detail you guys want to see in the upcoming video for making this die I can do them quick in an overview or I can really get into all the minutiae I'm sure there's going to be some some fun and rewarding moments and there'll probably be some stressful ones and some scrapped parts leave a comment below let me know what you guys want to see the level of detail length of the video if you like this please do me a favor and give it a thumbs up otherwise that's all for now folks see you soon