Hybrid 30 caliber PC Smooth Sided Bullet Mold

[HollowPoint]

After reading a few of the threads about getting good repeatable MOA 100 yard accuracy at 2000 FPS and above, I am surprised to find that few if any of the Powder-Coat guys seem to have gotten to that stage yet. I haven't either but, I'm just about three weeks into the Powder-Coating craze.

In similar fashion, when I first joined this forum I looked for ways to get good repeatable 100 yard accuracy at the highest possible velocities with Cast and lubed rifle bullets. My best accuracy was found at about the 1600 FPS velocity levels.

I thought maybe with the synthetic jackets that Powder-Coating now gave our cast lead bullets this might be just the thing to give my rifle bullets the kick in the pants to up the velocities and accuracy. I have yet to get to the range to shoot my first batch of PC'd bullets cast from a conventional mold. I'm more than sure my PC'd pistol bullets will perform the same or better than they already do with just lube on them. It's my 30 caliber rifle bullets that I want to get more velocity out of; without loosing accuracy.

To that end, I fished around in my junk box looking for a few chunks of scrap aluminum stock, some steel bar stock and a good strong spring. I found all of the above but I still had to shell out about seven-bucks for some drill-rod. (tool steel)

I used it all to make up a double cavity smooth-walled Hybrid 30 caliber bullet mold. It was designed to cast large mouthed Boat-Tailed, Hollow-Pointed Soup-Can shaped lead slugs; which in turn will get their noses swaged to final form.

I made the Hollow-Pointing pins adjustable so that I didn't have to build various bullet molds in order to get different weight bullets. The size of the Hollow-Point cavities remains the same but, by adjusting the Hollow-Point pins inward, I get a shorter lighter bullet. Conversely, by adjusting it out, I get a longer heavier bullet. The nose is swaged to the same shape regardless of bullet length.

I finished up the mold and the swaging die today. I have yet to cast with it. It's been raining cats and dogs here in Arizona lately. If I get some free time this weekend I'll see if this project was worth while or not.

From what I've read, I've come to the conclusion that PC'd bullets really don't need lube grooves so I did away with them, which made the building of this mold a whole lot easier.

I had to make three different reamers to finish this project. One to shape the profile of the nose-swaging-die, One for the bullet cavities and another Boat-Tail shaped reamer for forming the cup on the end of my push-thru-pin on my sizer.

I have a busy day at work tomorrow so it may not be until thursday that I can take some pics to show you all what I'm talking about. With any luck, the design of this Hybrid bullet mold will address some of the issues that may be keeping us from attaining the velocities and accuracy we strive for.

HollowPoint

[greenhornet-1]

Very interesting!

[xacex]

I have been looking into doing a hybrid mold from Accurate that is a non tapered PP mold slightly undersized, an a gas check shank for HV work. I don't know which caliber to start with, but it will most likely be for the Beowulf, and copy dimensions of a Hornady 500 grain bullet that is very accurate in these guns. Most likely would not require a GC shank, but if I am only doing one I might as well.

[HollowPoint]

I'm happy to report that my efforts weren't completely in vain; at least not with the casting and swaging aspect of this project.

I got a chance to cast a few bullets with my new Hybrid bullet mold and for the most part, everything worked as I'd hoped. I did encounter some problems with the Swaging part of my plans.

Those problems stemmed from making my Nose-Swaging die with no support for the body of my bullets so as I applied the pressure needed to form the noses of my bullets, if the cast cylindrical slugs were even slightly off-center, they tended to bend into a non-concentric state.

Looks like I'll have to make a new set of dies with the correct amount of body support.

I was able to finish a couple of bullets just to prove my concept. It looks like this idea just might work.

I used some imported 5/16" Drill Rod to make my reamers. 5/16" drill rod is supposed to measure .3125". Mine measured .311". I got this size so that I could minimize my time at the metal lathe by just having to machine the bevels of my Boat-Tail angles and the curves of the bullet noses. It's easy enough to size down from .312" to .309".

I'll post updates once I get my new swaging dies made up. I made my present dies to fit my re-loading press. It's a coaxial type of loading press and it wasn't really made to handle the kind of stress that bullet swaging puts on it.

With this new set of Nose-Swaging dies I'm going to make them to fit my 1/2 ton arbor press. With my present set up I was afraid to break my reloading press by forcing the noses on my cast bullets to conform to the shape that my reamer cut into the inside of the swaging die.

All in all, I think it's really going to work. Now, that doesn't mean the bullets will fly accurately and at higher velocities but, that's what I'm shooting for; so to speak.

I'll be back once I get farther along on this project.

HollowPoint

[el34]

Man I am really impressed. I hope it all works, and I'm not the only one that'll be watching for your posts.

[HollowPoint]

I got some time to do a little more tinkering with the swaging die I previously made and I now got it to swage not only the cylindrical hollow pointed slugs that I'm casting out of my newly made adjustable bullet mold but I can also swage the cast rifle bullets I cast in my hollow pointed Lyman 311291 mold.

This is a good thing for me in that I can now swage 30 caliber bullets out of my Lyman and NOE rifle bullet molds. This is in addition to the various sizes I can get out of my home made Hybrid mold.

I'm happy I was able to get this swaging die to do this using my cheap 1/2 ton HarborFreight Arbor Press. The thing is, I really want to try the smooth-sided bullets I'm swaging from the Hybrid bullet mold I made up.

After swaging them into the Boat-Tail configuration the only difference is the overall exterior profile. The weight remains basically the same; and -I think- swaging them may mitigate any possible voids they may have developed during the casting process. At the very least, the swaging of these bullets may address these unseen voids to reduce or eliminate their effects on concentricity and accuracy. Time will tell.

Since finishing up this first prototype Hybrid adjustable bullet mold and swaging die, I've begun phase II of this project. Phase II involves the fabricating of better reamers in order to get a better finished bullet mold. In the past my reamers were straight-fluted reamers that, when used, tended to give less than stellar finishes on my mold cavities.

I have made it a priority to learn how to make up some spiral or helix fluted reamers in hopes that they will clear out the metal shavings as I'm cutting the cavities in my molds. In the past it seemed that my reamers were cutting cleanly but, since the shavings remained in the cavities as the reamers were cutting, the flutes on my reamers tended to run right over those metal shavings causing poor finishes on the walls of the cavities.

Another thing was that after hardening those reamers I made out of 0-1 drill rod, I never followed that up with any kind of Tempering. I'm not sure that Tempering was needed when machining aluminum bullet molds but now that I'm thinking of making me up some bullet molds out of iron or steel, I don't want the brittleness of my hardened drill rod to cause them to break while they're cutting the cavities. I'm still looking for information on exactly how to go about Tempering hardened 0-1 tool steel drill rod.

If it all pans out and I'm able to get MOA accuracy out of these 30 caliber bullets after PCing, I'll think about scaling down to .224 so I can try some out of my Tikka 223.

I'll be back when I get far enough along.

HollowPoint

[popper]

Please keep us informed. If I had tools to do that kind of stuff I'd never get to shooting. Are you ready to take production orders yet?

[HollowPoint]

Any of the shooting related stuff I put together I make for myself. I've thought about making and selling my home made items but that lost its appeal when I too realized that if I started making stuff to sell, I'd never get to go out and shoot. As it is, I have very little free time to go out and shoot any way.

I finished up my income producing work early today so I drove down and picked up some more metal stock. I was able to get started on my new swaging die. Midway through the reaming process I managed to break a couple of small sections of one of the flutes on my reamer. This is what I was eluding to in my previous post about "Tempering" my reamers after they've been hardened. Now I have to make up another Nose-Shaping reamer to clean up the faint flaws in the wall of my swaging die.

Depending on the type of metal you're making your dies out of, it's better to "Temper" them so that they're not so brittle that they break when you're cutting your cavities.

I also figured out how to draw up spiral fluted reamers in hopes of mitigating the breakage of the flutes due to them binding up on the metal shavings that accumulate inside the cavities of the die. Now I just have to figure out how to run them through my CAM software to generate the G-Code for the CNC mill.

If I get a chance I'll post my computer rendering of the Spiral-Fluted Reamers I'm hoping to machine in the not to distant future. I'm not a machinist or a CAD/CAM software guru. I'm a self-taught goober and alot of this is just trial and error learning for me.

I'll be back as I get farther along.

HollowPoint

[popper]

IIRC use oil quenching to temper. You are having FUN!

[leadman]

When I finish ream a barrel chamber I only cut about 1/32" and back the reamer out and clean and oil it. Could you back your reamer out and use a vacuum or air nozzle to clear the chips out?

[HollowPoint]

I've dredged up this old post to let you all know that I finally finished up my most recent bullet/slug mold for the "Smooth-Sided" 30 caliber swaging die I made up earlier.

This time around I made it a single cavity slug mold that is also adjustable for length and weight. It will cast a hollow pointed cylindrical slug that will then be swaged to final form.

I've taken some pics but I'll wait till tomorrow to post them since I hope to be able to cast up a few slugs in order to show you all how I intended for it to work. This is by no means the end of the project though. I still have to rig up a Powder-Coating jig that will allow me to rotate my cast bullets so as to apply an even coat of PC with no overlap; or at least a minimum of overlap.

I'm hoping that this method of application will mitigate as much of the uneven-ness that may be causing the loss of concentricity in the final product.

The reason for going with a single cavity mold this time around is two-fold. First; this is just an experimental type of project and I didn't want to spend a whole lot of time and effort on something that might not pan out for me in the end. Secondly; I'm Cheap. I ran out of aluminum stock and I didn't want to go out and buy some more so I used a piece of 1018 mild steel that I had laying around as my mold block material.

Remember, all I'm using this mold for is to cast cylindrical hollow pointed slugs. I don't need them to drop from the mold at the precise dimensions that some aluminum, brass and iron mold makers claim to get out of their molds with specific lead alloys. So, please don't bust my chops about using 1018 steel for my mold blocks.

If my casting session goes as I hope tomorrow, I'll then get rolling on the Rotating PC jig I've eluded to. I've already got an idea how I can get this to work. It's just a matter of gathering the components. If I can get them all cheap enough I'll buy them in order to save time; otherwise I'll have to fabricate them. I don't have alot of free time so If I have to make this stuff myself, it could take alot more time.

I'll be back with pics and updates as time permits.

HollowPoint

[fastfire]

I like the boat tail idea, then PC.

[HollowPoint]

I got some time to break in the new slug mold I mentioned in my previous post. I've also included a few pics so that my ramblings make a little more sense.

I'm happy to report that both the bullet mold and the swaging dies worked as I'd hoped they would. I am thinking about going back and reshaping the nose forming part of the swaging die so that it forms a more streamlined nose section on my finished bullets.

Next up is the Powder Coating jig that will slowly rotate my bullets as I'm applying the Powder. I'll start looking at various sources for the gears I'll be needing as time permits.

In the mean time, this is what I've finished up so far. I'll be back when I make a little more head way.


HollowPoint

[leadman]

If you would consider using the Hi-Tek coating you would not have to make a jig to spray them with, just tumble and toss on the screen. Don't know where in Az you are I am in Phoenix and can Hi-Tek coat some of these for you if you would like.

The boolits do look nice and I hope they perform for you.

[HollowPoint]

Since this project started out as a PC project I plan to see it through to it's completion this way. If it doesn't pan out as a PC project; I mean, if I don't get the desired results with PC, I hope your offer of HT coating will still be open.

I figured if it doesn't yield the velocity and accuracy results I'm hoping for with Powder Coating, I'll try it as a Paper Patch project.

HollowPoint

[popper]

I'd like to see you DTPC some and give target results prior to a PC jig. I'm shooting basically slick sided PC rifle and results are fine. The nose closes into the HP volume. One user has triple coated the Lee BT and gotten reasonable results, interesting to see yours.

[HollowPoint]

We bullet casters have a ton of acronyms associated with our hobby. Here's a few more.

SW, CB, 30-Cal, HP, RBT, PC'd, HF-WB's

That's; Swaged, Cast-Bullet, 30 Caliber, Hollow-Pointed, Rebated-Boat-Tail, Powder-Coated Harbor Freight White-Boys.

Just a quick update on my latest efforts.

I took a little more time to figure out the nuances of swaging my newly cast lead slugs. I found a flaw in my swaging die but I was able to work around it for now.

I'm going to go ahead and load these up as plinking loads using lighter charge weights. I want to see if they'll fly straight; no wobbling or key-holeing.

If they fly true, I'll push the next batch a little faster. In the mean time, I'm still working of gathering up the stuff I'll need to make my Revolving Powder Coating Jig.

I decided to coat them with some Harbor Freight White powder.

With the bullets that still had visible hollow points, I was able to stand them nose-down on a metal pin and powder coat them in one session. Those bullets effected by the flaw in my swaging die, I had to coat them in two sessions; one for the nose and one for the tail. I much prefer applying the Powder Coat in one session. It makes for smoother looking bullets.

Under the pressure of the swaging process, the hollow pointing pin hole on the end of my nose-forming die acted as a Bleed-Off hole. Lead extruded out of that hole causing a Pinocchio-nose effect.

When I went back and trimmed off that extruded noses, it caused my hollow point cavities to be plugged up so I wasn't able to stand them up for Powder Coating in one application.

Live and Learn. I ended up making a new hollow pointing pin to plug the hole at the nose of the nose-forming section of my die. This new hollow pointing pin actually screws into place so I'm hoping it will keep me from having to make a new nose forming section.

I'll be back when I get farther along.


HollowPoint

[TreeKiller]

When I went back and trimmed off that extruded noses.

NO NO NO Drill a hole in something and use this nose to stand them up in and PC with one coat and then cut it off. Of course you have lost the hollow point you are trying to achive.

[HollowPoint]

TreeKiller: Good idea. That never even occurred to me. If the new hollow pointing pin setup I just made doesn't work out I'll give your idea a shot.

The draw back about cutting the extruded nose off is that I end up not only with the hollow point cavity closed shut but, the point of my bullets end up being unevenly cut. Not one of them is the same; which mitigates any kind of consistent duplication.

Still, it's a good idea. I'll try it on the next go around.

HollowPoint

[popper]

Cast a much shorter slug (HP pin longer), then swage? Could probably get it adjusted to leave some HP in finished product?
They do kinda look like those shoulder fired warheads.