Hollow Pointing – A Lathe Option

[JIMinPHX]

Hollow Pointing – A Lathe Option

I recently started casting for the .223. After reading Beagle’s posts about his success with hollow points in that caliber, I decided that I should try them as well. The problem is that I have heard rumors about HPs being hard to cast & I didn’t want to permanently alter a mold that I already kind of liked, especially if the HPs ended up not wanting to cooperate in my gun. That left me thinking up a way to stick a hole in the end of a boolit that I already had made.

The first thing that I had to do was find a way to get a good reliable grip on a boolit without deforming it. Since I don’t have a collet closer on the little refugee-from-a-junkyard lathe that I had handy, I ended up making a ghetto collet. I basically just turned a shoulder onto a piece of plastic, reamed a flat bottomed hole that was a few thousandth over the raw boolit diameter, & split the whole thing 3/4 of the way across with a hack saw. It’s shown here with a finished HP in its grip. It actually works well. Concentricity is better than I expected.

[JIMinPHX]

The next step was to get a tool to the work. I wanted something that was easily repeatable for depth & rigid enough that it wouldn’t walk off center when cutting the hole. I ended up making a quick little drill holder out of a piece of hex stock & securing a short drill bit with a set screw.

[JIMinPHX]

Next, I set up a cheesy little carriage stop that was made out of a small C-clamp & a scrap of steel stock, which also worked pretty well. Then I had at it & started poking holes in some lead. Now, I’ve never drilled lead before, so I had no idea what kind of tool tip geometry lead likes to see. I also just guessed at the feed rate & spindle speeds that would be suitable. I ended up going about 1000 RPM with a 3/32” screw machine bit & feeding with 3 stops to break the chips. As long as I touched a bit of oil to the drill bit before I started & as long as I didn’t spend too much extra time with the bit in the hole, all went well. If I used a dry bit & let it sit in one place too long, the led got hot, the bit locked up & the boolit spun in the collet. There were no broken tools or anything though.

[lathesmith]

Nice work, Jim. That should give you a few hollowpoints for testing, and your technique is fine. I wouldn't worry about being a few thou off on concentricity--if your drill is stiff, your boolit will end up being concentric enough. Let us know how they shoot!
lathesmith

[JIMinPHX]

This is what I ended up with a few minutes later. All in all, I’m pretty happy with this. It gave me what I wanted without committing an additional mold to the project.

[targetshootr]

Looks pretty good. I think I'll send some for that treatment. What kind of price are we looking at?

[JIMinPHX]

I just completely guessed at how much of a hollow point to dig out. I used a diameter that was just under the size of the meplat & I went in to a depth that was even with the bottom of the ogive. I’m thinking that this may have been a bit much. If anyone has any info that would help me select a proper size hole for the front of these things, I’m all ears.

Thanks,
Jim

[beagle]

Jim, they look good. I used a .070" cavity pin for my .22s but your's look pretty good as well. I don't have alathe and have to depend on my shooting partner.

After you get use to making the HPs, you can really turn them out.

The .22HPs really blow up starlings...../beagle

[JIMinPHX]

Looks pretty good. I think I'll send some for that treatment. What kind of price are we looking at?

You mean that you want me to poke a few holes in some boolits that you already have made up? If you just want a small handful done, It's no big deal. I'll just do them for you. ...that is, if I don't have to go making up new tooling special for an odd size that I wouldn't end up using myself eventually. What caliber do you have & what size hole do you want?

[JIMinPHX]

Jim, they look good. I used a .070" cavity pin for my .22s but your's look pretty good as well. I don't have alathe and have to depend on my shooting partner.

After you get use to making the HPs, you can really turn them out.

The .22HPs really blow up starlings...../beagle

If your .070" holes "really blow up starlings", then my 094" holes may be a bit much. I quenched them to 23BNH, but I'm still concerned that they may open up before leaving the muzzle since the metal at the nose is so thin. I was going to push them around 2Kfps out of a 1:12 twist barrel.

[jhalcott]

I never tried this with such tiny bullets but 30 caliber and larger bullets worked fine when I HP'ed them in a tool room lathe . I tried the hollow pointer from some company that used an 1/8" drill. I did not think they were accurately centered though, and groups proved it. With the bullet spinning in a collet and the bit in the tail stock, the results were much better and MUCH more accurate. I didn't "blow up" any bullets in the bore ,but did play around with some rather large holes. There seems to be a point that causes instability and the "groups" will grow into patterns. Each bullet style and alloy will have a different point of instability. You must test them at the LONGEST range intended,They can be very accurate at 50 yards with no accuracy at 100+.

[lathesmith]

Lathe hollowpointing should work fine for most any shooting I do. I dumped my Lee 357 HP mold on ebay some years ago, and I was astounded at the high-dollar price it fetched. I think if I actually get around to feeling the need for HP's in a particular caliber, I like Jim's idea of making up a split holder. The only change I would make is to use a collet chuck, but I'd say with the right setup one would be hard-pressed to tell the difference from a good 3 jaw chuck. The main advantage in this case would be the collet should be just a little faster. Also, for the larger caliber I would be inclined to try a center drill; this would be the ulitmate "stiff" bit and should be plenty deep.
lathesmith

[xr650]

Jim,
Looks like a pretty slick setup to me.
It works well and that is all that matters.

[beagle]

With the velocity of even .22 cast and I'm shooting at 2000-2200 FPS, any diameter HP will blow pretty good. But, that's good as we're wanting max expansion on varmints and no richochets.

I'm betting yours will make darn fine varmint bullets. Keep us posted on the results./beagle

[JIMinPHX]

Lathesmith,
A center bit was the first thing I set up & tried. I just wasn't able to get it in deep enough on such a small boolit. That’s why I went to a 3/32 screw machine bit. It seemed to give me the best combination of available depth & rigidity. I could back it up in the holder some more for even greater rigidity, but I think that I'm better off keeping the chip clearance passages open.

With a little luck, I may be able to try these things out tomorrow.

[JIMinPHX]

Well, I managed to squeeze in a quick little trip to my favorite shooting spot. I got off 5 rounds of the new hollow points & 5 rounds of the same thing without the hollow point for comparison. Each used 10 grains of some old 2400 powder that I had kicking around, LC brass & a WSR primer. The 48.5 grain HPs were doing a little over 2000fps. The 54-grain FPs were a little under 2000. I was sitting on the tailgate of a truck & shooting casually at 50-yards, so these are not exactly bench-rest groups. The results do tell me that these HPs have some promise. Their group seems no worse than the flat point group. The size of the groups is probably more my fault than the ammo’s, so please take that with a grain of salt. The squares on the targets are 1-inch across.

The23 BNH hollow points started out at 48.5 grains, but I only recovered 27-31 grains of each. Anything forward of the bottom of the hole was just gone by the time they went 11-14” deep into crumb rubber. I did find a few stray fragments here & there, but they were small. Based on the fragments that I found & the shape of the holes in the target, I believe that the HPs did hold together until they hit the rubber.

The 13BNH flat points started out at 54 grains & lost almost nothing. They went into the crumb rubber about 20-22” deep.

[JIMinPHX]

I was wrong, those groups were the fault of the ammo. I just tried 5 rounds of the cast flat points against 5 rounds of some j-word handloads that I made up for a different rifle about 5-years ago. The J-words gave me a group the size of a golf ball. The cast gave me a group that was a little bigger than a base ball. I think that my powder may be my problem. I was loading up the cast with some second hand 2400 that is older than dirt. I may need to relegate that can of 2400 to plinking only.

[MtGun44]

I'd try Buckshot's recomendation of 4198 before I'd assume that there was
something wrong with the 2400.

IMHO, it is much more like to be the WRONG powder than BAD powder.

Bill

[JIMinPHX]

The only thing that makes me think that it is not the wrong powder is because Beagle had good luck with 2400 in his tests. I will try some different powders though. Thanks for the opinion.

[bruce drake]

Every Lot of Powder is different. You might tap the sweet spot with a little variance in the powder charge.

[JIMinPHX]

Just a quick update - I'm seating the boolits out further now & getting much better accuracy.

[lwknight]

Just a thought, What if you swaged the point smaller leaving the larger drilled cavity below. It might help balistics and not affect the HP performance.

[Dutchman]

A suggestion...

Put your nose drill/cutter in the lathe collet and the bullet collet in your QC tool holder. This way you don't have to turn the lathe on and off in a gazillion cycles. The lathe stays running and you change out the bullets on the tool holder. You can get a collet adaptor for the various QC tool holders. It would initially take some more time setting it up and indicating it in but it'd be much faster.

You could also make a simple tailstock bullet holding collet and the same would apply, leave the lathe running and just dial in the tailstock to a preset stop for hole depth.

Dutch

[JIMinPHX]

A suggestion...

Put your nose drill/cutter in the lathe collet and the bullet collet in your QC tool holder. This way you don't have to turn the lathe on and off in a gazillion cycles. The lathe stays running and you change out the bullets on the tool holder. You can get a collet adaptor for the various QC tool holders. It would initially take some more time setting it up and indicating it in but it'd be much faster.

You could also make a simple tailstock bullet holding collet and the same would apply, leave the lathe running and just dial in the tailstock to a preset stop for hole depth.

Dutch

Now that's thinking with your head.

Maybe I could set up a nest fixture on the tool post with a DeStako clamp for even quicker change overs.

Then again, maybe I could make a fixture for a drill press.

You've really got my wheels turning now.

[JIMinPHX]

Just a thought, What if you swaged the point smaller leaving the larger drilled cavity below. It might help balistics and not affect the HP performance.

Good question. When I get the time, I may try that out.

[Frank46]

You could use a center drill, they come in about 5-6 different sizes. Use your nylon chuck with drill chuck in tailstock. Lock down the cross slide as a stop and away you go. Think it would work more efficiently than just a plain drill bit. Maybe this would work in your case. Frank

[JIMinPHX]

Aluminum split collets work a little better than the plastic ones do.

[x101airborne]

also just try a small pistol primer with the 2400. shrunk my red dot 30-30 loads by 2 1/2" @100 yards

[Bass Ackward]

I'd load about 17.5 grains of IMR 4895 and watch'em sing.

[NoDakJak]

Dutchman I really like your idea. I'll try adapting the idea for my own use. I have been chucking up loaded 44 Special rounds in a three jaw chuck and hollow pointing them with a center drill. They are loaded to approximately factory velocity and recoil is still no fun in my Target Bulldog. Boolits are some old Taurus, 240 grain swc's that I have had laying around for years. Expansion still seems to be almost non-existent at that velocity so I have turned the complete nose off of a couple dozen for test purposes. That .430 diameter flat nose should be the ultimate stopper. Neil

[Bass Ackward]

Here is another option to get you thinking of possiblities. It has proven to be just as accurate for me using several calibers. The only disadvantage is that I had all my chamber reamers. Works by hand pressure in a lathe, or a drill press.

[DeanWinchester]

I make hollow points on my lathe for .45 LC. I start out with a Lee C452-300-RF
I use a Garr carbide endmill, 10 degree taper with a ball end. Set it up in the drill chuck and plunge to almost fiish depth, leaving myself a small amount for finish. Then I size/Lube/seat the gas check and with the end mill in the lathe chuck this time, hand finish to final weight which ends up being 280g +/- 1 grain.


http://img.photobucket.com/albums/v484/iluvmyferrets/photo-4.jpg
http://img.photobucket.com/albums/v484/iluvmyferrets/photo-2-1.jpg
http://img.photobucket.com/albums/v484/iluvmyferrets/photo-3.jpg
Yes I know the picture shows the bullet without lube/gas check, I was just trying to get a pic.

[DeanWinchester]

THis makes a REALLY deep cavity. I use a bit of sewing machine oil to keep the end mill from loading up. I only recently started making these and have not had a chance to test them out yet. Cast from WW they fall a bit heavy @ 305-308g from the mold. Sized/lubed/GC without the hollow, they run 320g.

These should be impressive around 1100FPS or better.

[DeanWinchester]

If only I had a reasonable way to make a plastic tip for them and superglue them in place, I'd have a cast version of Hornady's FTX.

[MaxJon]

Lathe hollowpointing should work fine for most any shooting I do. I dumped my Lee 357 HP mold on ebay some years ago, and I was astounded at the high-dollar price it fetched. I think if I actually get around to feeling the need for HP's in a particular caliber, I like Jim's idea of making up a split holder. The only change I would make is to use a collet chuck, but I'd say with the right setup one would be hard-pressed to tell the difference from a good 3 jaw chuck. The main advantage in this case would be the collet should be just a little faster. Also, for the larger caliber I would be inclined to try a center drill; this would be the ulitmate "stiff" bit and should be plenty deep.
lathesmith

Thats exactly what i will be trying when i get my Lee soupcan mould! (Lee#90362-.309)Hold in an ER32 collet chuck and poke a No.4 centre drill (1/8" dia pilot) in until the 60 degree taper starts. I think thats about 1/4" deep (approx) Should work fine i think?
BB03