DBCstm handmade build... Finished Light w/stand end of thread 6-21-13

Ok, I’m in. I have no idea if I can pull this off but I’m game. But I need to check a bit on some basic rules. Tabletop drill press is out, correct? But a cordless drill and dremel tool are ok? This should work ok for me, as the El Crapola benchtop drill press I have would ruin things if I tried to use it. Ask me how I know lol.

Also, is there a plan for the lights after they’re built? I’d like to gift this one to my neighbor who’s generously supplying the basic raw package without really having a clue what is going to become of it. He’s a L.E.O. and into WWII era paraphernalia so it’d only be fitting, if I’m successful, to gift it back to him.

So, all this said, here’s my “package”

The one on the left. Well, sorta. This one’s a dummy round with holes in the cartridge. The real one will be a fresh brass cartridge with shiny copper bullet. The MBI HF in Cu is for size comparison.

The Plan: Pull the bullet from a live .50 cal round. This will be turned down slightly to allow it to slide in the neck. It will be attached to a McClicky switch and the copper bullet will be the on/off clicky itself. I plan to cut the cartridge to gain access to load optics/emitter/driver/cell. Will rig a thread into the cartridge, probably just under the necked portion, to allow battery changes. Open up the primer end, after firing the primer and removing it of course, for a TIR optic on a XP-G2 relowed to Nitro’s copper star with a 1/4” copper heat sink behind it, driven by, well we’ll see. I have a driver in mind that should run the emitter at 1.4A with 3 modes with memory and low-discharge protection. So if it works out, it’ll be running something like 250 lumens on high (OTF), and look like a live .50 cal round when standing inert.

Oh boy, I think I’m in over my head! :slight_smile:

Edit: So I figured out how to pull the bullet from a .50 Cal round. I formed 2 pieces of 12ga copper wire to fit into the retractor slot of the base on the cartridge. Then found a pipe of the correct diameter for the bullet to fit into such that it would press the copper pieces into the retractor slot to act like a collet. Then some serious banging on a large piece of steel and the bullet was dislodged by inertia. A bit scary, that part! But here ya go…the body.

Beside the BBC 261L (cause I just really love looking at it!) and the 14500 cell I plan to power the light with.

First thing was to get the prime out and start preparing for an TIR Optic. This sounds easy but the primer is this bad boy was equally stout! I think this is a Berdan primer, instead of an anvil in the primer cup, a post is machined in the casing itself with a charge hole on either side. This post made a drill bit want to slip off center, so I had no choice but to dremel it out.

This one lets you see the post better. The dark or black is the bottom of the primer hole where the spent powder burned the brass. Of course, the primer had to be discharged after pulling the bullet in order to get going on this build.

A bit better look at the reamed out primer cup hole with the pinch post still standing but a bit worse for the wear

A nice little pile of brass shavings and some toasted fingers later…

Ahh, who would have thought the base of a .50 Cal round would have 5/16” of brass under the primer? Hopefully that’s the worst of it, we’ll see! :wink:

Plan to reflow the emitter on a Nitro copper star today, we’ll see if I have to turn that down to fit…my luck, probably so. lol

When discussing building this with my neighbor, Steve, I was thinking to make the copper bullet a twisty action to turn on the light. He thought it’d be cool to make it the pushbutton for a clicky. So this is what I’ll be attempting, provided I can get a clicky switch inside of course. So once again, I might have to do some fancy footwork on virtually every component to pull this off. And once again, I am thinking I may be in over my head! I’m a photographer, not an engineer, but hey, how hard could it be?

New pics 6-13-13 Step 2: Body prep

The build ingredients, XP-G2 R5 2B emitter, Ledil Tina2 RS TIR Optic, McClicky switch and potentially this 10mm driver with 1.4A 3 mode…might change that to a 3.04A Q-Lite driver.

I cut the cartridge to start working the insides…

Finished up the external mount for the TIR…

And got the TIR fitted…

New Pics 6-13-13 PM Step 3, 4, 5 The Pill

I got busy today and made some good progress. Had to square up the inside of the “head” section, while the cartridge tapered up on the outside, it tapered down on the inside to form a bowl with very thick walls at the platform. So I squared that up, then worked my tail off cutting a rough circle in a 1/4” bar stock (This stuff is hard, it was a bus bar in the telephone company back in the 50’s) Then had to file it down to get it close then finish with sanding using a glass table top to keep it square, so I could get it round! :slight_smile: Then cut a piece of 3/4” copper pipe and fit it so that it’d make a shelf for the driver. Whew!

The squaring of the head…

The parts…

1/4” thick copper heat sink, with copper shelf for driver…

Testing fit…

Bird’s eye view, looking down inside the “head” which is of course the bottom of the .50 Cal cartridge…

My fingers are about wore out! I held that little slab of copper in my fingers the duration of filing and sanding it down, hand work never got more manual than this! The rest can wait til tomorrow…

Step 6, Body and Pill assembly

Ok, today I went to town and studied the plumbing section at Lowe’s very carefully. Ended up with a 1/2” compression fitting. Cut the threads out of the fitting and put them in the light, sounds easy, right? LOL Then I put the pill together, and it checks out perfectly! I’m using the Q-Lite 3.04A 3 mode driver with the XP-G2 R5 2B emitter glued to a slab of copper. :slight_smile:

The threads…

These will still have to be glued in, but that has to wait till the pill is dry as well as the TIR, which is glued into the head from the outside…

Pieces fit together and thread up quite nicely, a very snug compression fit with zero room left for adjustments…

I’ll work on the visible line and finish when I get everything fitted and working. The “head” has been handled a lot, so it’s taken a bit of a polish from handling…

Between this chunk of copper and all the surrounding brass, heat should have no problem figuring out where to go…

The Q-Lite driver in the pill. I’ll have to ream out the male threads a little more, an Alkaline AA fits easily but a Protected AW14500 doesn’t.

And it’s time for today’s installment of alcohol. :slight_smile: But I’m very happy with progress, and it feels good! :wink:

Step 7, Fitment and testing

So, it’s supposed to work something like this…

No, it’s not finished, but it works! :slight_smile:

Step 8, Finish

And now that it’s fully assembled, with it’s batteries on the way, it gets a polish. Let’s call it Gunner’s Dress Blues .50 Browning Machine Gun or GDB .50 BMG for short.

I need to do some tweaking on the overall inside length, but have to wait for the correct batteries to get here for that. The AW and Intl-Outdoor cells are protected and longer than standard, so I will probably create a copper spacer to allow those to work as well.

Happy Father’s Day!

Step 9

Improvised a work-around to use the cells I have on hand, temporarily. This enabled some working pics. AW IMR 14500 cell should be here in the next couple of days so I’ll get full working amperage readings then and possibly take some more pics. But til then, enjoy!

Beamshot settings set up for the medium level to show difference in beam modes.

Not too shabby! :wink: There’s a dark artifact in the center that’s barely visible that really puzzles me, other than that, it’s a whole lotta light!

To bring some of the finished pics from the end of the thread to conclude this build, here’s the way it ended up:

With the AW IMR14500 in the light, it closes completely when on for a near seamless finish. I added a copper wire bypass in the spring on the driver to get a 2.82A reading off this cell. And to finalize it, I created a stand to give the light a “Rocket Ship” look when on the shelf. :slight_smile:

And for posterity, this “poster”…

A real fun challenge, Thanks Old-Lumens, brilliant idea!! :slight_smile:

good idea, looking forward to seeing it finished (i like the rusty finish, maybe you should make both shiny and rusty versions!)

That’s Tacticool!

good idea! cant wait to see that .50 cal loaded up

Yes a drill press is out. Another very unique start! This is really going to be a hard contest to judge. I love it!

No plan for the lights. I was hoping they would be gifted to someone or in a giveaway here, but it's up to each contestant what they do with them.

I had my neighbor, the cop who supplied the .50 Cal round in the first place, assist me with the disassembly of said round. Told him what I was planning on doing and he’s really interested…“if it works out, I’m gonna have to get you to build me one!” lol

I’m putting it on “paper” that it’s going back to him when done, so that I won’t even think about keeping it for myself! :slight_smile: Gonna be hard to part with after all the work, I’m sure.

So now that I have the components, sans propellant, I can start trying to get it all assembled. The fun part! Wish me luck! :wink:

Steve McQueen would be proud :bigsmile:

Nice DBC. Weren’t rules made to be broken?

This is genius!

thats what i was thinking... just have a 3" head machined out of copper and all pieces threaded, and claim i did it by hand with a precision file

The “rusty version” is a dummy round, made without the Berdan primer pocket and with 3 holes in the cartridge case. Probably made for training purposes to simulate actual weight and feel. So, it’ll be a polished brass case with polished copper bullet. Speaking of the bullet that thing is massive! There’s enough lead in there to balance a truck wheel! lol Thinking that I’ll remove the lead to lighten the load, we’ll see. Might melt the lead out of the copper bullet, then fill it with JB Weld mixed with the brass that came out of the primer pocket, this would give it extra strength for drilling and tapping to put a bolt in it for…but I digress…

I thought if I had it made at the machine shop down the road, then marked it up a bit with the “precision file” it’d be all right? No? LOL. This one’s gonna be difficult all the way it appears. That would have to be the case, of course, for my 1st attempt. :wink:

We’ve got til October to finish this, don’t we?

And only gimped up Aussies are allowed to break the rules, ROFLMAO

Looking good. I’ve never seen a 50 calibre round but if you go to youtube, they certainly pack some recoil.

Government brass will almost always have two holes in the primer pocket and the primer is crimped, I think. Not just pressed in like us civvies do. Foy has pressed a lot of ammo over the years and I don't even bother with military brass.


You are making things too hard on yourself. If you had just whacked the primer with a hammer/nail, you could have killed (at least) two birds with one stone… the primer would then be inert and the bullet would have removed itself. J)

Probably three birds, maybe more. I like your pics better than mine.

The TexasPyro way would have added me, the cop and his son to birds killed! :stuck_out_tongue:

The primer cup was a byat*h to get out. Then the strike post was very solid as well. But that’s all done and the TIR is fitted, sitting slightly recessed into the casing. :wink:

Thanks RBD, still using the point-n-shoot, will break out the big guns when it’s finished (if that happens)

Have more pics, not at my computer. Will update later today.

That is really something else. I am so glad you guys took up the challenge. We are getting to see some great ideas!!

…wait for it….



Thanks O-L, prec8 it.