Making a Cast HP with a Drill . . .

Last week I came across an interesting video about using a drill motor and a home made jig to make Hollow Point Cast projectiles out of your solid casts you already have. This way, you don’t need an expensive HP mould to get into loading and testing the HP Cast.
This is the video I saw . . .

Home made hollow point bullet jig

Following this method a caster would first have to make a specific jig for each caliber he wanted to HP. Not all of us casters have the tools in their shop to do this method…it appears to be a great way to have a home made HP’ing jig and it does address the typical problems we have in keeping that HP cavity centered on the front end but I started wondering if just maybe we already had the parts and pieces needed to do this and didn’t realize that.
Before I go any farther I want to recognize a fellow hand loader that had already addressed this process I am going to expound on. I had not seen his video until one of the fellas on our chat channel pointed this out.  It’s Mike Treen and Mike published a video about two years ago doing almost the exact thing I thought I had discovered…check his video here.

hollow point making/Thanks to Taco!!

Thanks to Mike Treen, there’s nothing new under the sun for me today but I think I may have thought this process through a little farther and that is why I’m going to go ahead and write this article.
I wanted to address the problems people encounter doing this…

  • > centering the HP cavity
  • > drilling the cavity the same depth each time
  • > centering the cast in the jig

I looked at a ‘size die’ and thought that the threaded hole in the top of the die would would be a good way to use a drill bit in a hand drill ‘if’ I could ‘close fit’ the bit to that hole and use this die without damaging the threads. All I needed was a ‘collar stop’ for the bit to set the drill depth of the HP on each cast I made. This way I would have the drill bit centered on a solid cast ‘if’ the inside top of the die was tapered for the cast to center itself. This too was the case.
Next I thought I’d use the push post from a Lee sizing die to push the solid cast up into the size die and against the top of the tapered cavity inside the die. I ran out of luck with my pistol cast at this point, the push post is too short…hmmmmm…back to the drawing board.
Then I thought about using another cast to go under the cast I wanted to put the HP into and that worked just fine. Notice in the picture at the top of the page, I have the little 158 grain Lee RNF used as the spacer I needed between the 200 grain RN and the push post.
Here are all the components needed to make a HP drill jig and they were all in my shop without realizing this.

Making a Cast HP with a Drill . . . 3

This HP cavity is too large for the cavity as you will see in testing later. At this point it is advisable to grind the point of the bit to the exact shape and depth of the HP you intend to make…I suggest a cone shape with a depth about as deep as the cavity is wide at the nose of the cast. This would be a good shape and size to begin your experimenting.
Loads of Bacon has a terrific spreadsheet that will get you right in the ballpark for blending the boolit metal for the speed and caliber you want to shoot. I can’t begin to estimate the 100’s of hours and expense James has put into this. As far as I know, there is nothing like this out there in cyberspace…study the entries carefully and you will gain valuable hard earned knowledge of his work…free for the consumption! When your done…face towards Texas and blow James a few cyber-kisses for all his dedication to excellence in our arcane hobby.

PC Cast HP test results

Here are more links to this fascinating HP cast subject…

Powder Coated Cast Lead Hollow Point Bullet Testing Playlist

With this information behind us, let’s look again at this experiment in HP’ing a solid cast. As I said before, the size and shape of the cavity will be about 1/3 of perfecting your creation. Notice below how much weight came off this 38 caliber cast using this drill bit.

Making a Cast HP with a Drill . . . 5 BEFOREMaking a Cast HP with a Drill . . . 7 AFTER

Now this puts me into an entirely different load table…this is where we need be very careful in our load workups. Always start at the minimum for that weight range and profile and go up from there, carefully observing the shape of the primers and your chrono speeds. For most of us, primer shape and chrono speed are the only things that will indicate to us our pressures. Don’t get in a hurry, try to remember that every shot you make in a load work-up is part of your education in this hobby. All this is called empirical evidence, take the time to log your experimenting into a notebook and it always tells a story, just as Loads of Bacon’s spreadsheet does. The more information you log now, the smarter and craftier you get in a shorter time.

I had just this one home made HP I made in trying to develop a system to make them as described above. I didn’t think this full size drill bit cavity would make a good HP in this small 38 caliber slug but I like busting water jugs for giggles so I loaded this into a case and went for it. The video below will show the fun I had…


The recovered HP wasn’t much of a HP anymore, the whole front end of the HP cast is gone. Why? The cavity was too large in diameter relative to the diameter of the cast and the boolit metal too hard for the speed. It weighed 156 grains and lost the nose, lost the mushroom we wanted in the HP somewhere between the 1st and 4th jugs as it had broken into the 5th jug but fell on the bench between the 4th and 5th jugs where I found it.

Making a Cast HP with a Drill . . . 9

Not much to look at now, almost looks like an inverted Hollow Base Full Wad Cutter.
Well, that’s my story so far and I’ll stick with it. I’m not sure I’ll do anything farther with this homemade HP jig as I have all the HP moulds I need and can do the real deal starting at the casting pot. I wanted to at least show you fellas that HP’ing can be done outside the mould.

If this 200 grain RN cast looks interesting to you and you missed my previous video on experimenting with this ‘Police Special’ of yesteryear, I have a video linked in an article I wrote recently.

200g 38S Jug Busters _ Super Police Load of yesteryear

Thank you all for taking the time to read this article, I hope there is some information here that’ll be of benefit. Every time I go to the ‘RabbitHole’, my shop, I end up fiddling with something that I eventually share, whether it’s just some fun busting jugs or practice on the range or a multitude of other things I do… previously I would have encountered you to check my YouTube channel, but there’s no telling how much longer it’ll last anymore…they are trying to get rid of us every day. Consider shiwing all your videos in and becoming an author and writing your ‘tips-n-tricks’ for the rest of us to enjoy. My name is Charles Irby and my channel is here…


Be careful out there boys, have fun & keep that head on a swivel & watch that 6…the times, they are a changing!

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