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Shooter6br
02-13-2010, 04:25 PM
Tried a Lee 240 g 41 mag swc hollow pointd by drilling to 205 g deep hollow point. Load 7.5 g Universal .Shot into 2 liter water filled bottle backed bu 8 in tight newpaper. RESULTS: Wife watched as water soaked me ( I was about 5 yrds away in my crawl space. The bullet went straight thur the bottle impacted news paper(dry) It penetrated about 3 inches. To my surprise no mushroom.(see pics) Alloy was 20-1. The bullet lost 10 grains in weight.I beleive the bullet collapsed on its self. Maybe the HP was to deep (6/16) Killed the soda bottle though Rick

Hitman
02-13-2010, 04:55 PM
Is it possible that you were to close and bulltet was still at to high of FPS to catch proper expansion? Surly you were to close for the bullet to tumble. Maybe your alloy was a bit on the hard side, do u have a brinell tester?

Shooter6br
02-13-2010, 05:15 PM
No but the alloy was bought here from a vender he assured me it was 20-1 It appear softer than Lyman NO 1 The exit hole in the bottle was about bullet diamenter,Thebullets when pulled with my hammer type puller do deform on the bullet near the swc meets the main part of the bullet. i believe the
HP collapsed on the bullet main body and acted like a solid That is why i loved cast bullets An exercise is science and experimentation LOL The bullet velocity was about 1000 fps at muzzle

303Guy
02-13-2010, 05:56 PM
Might I suggest that the hollow nose part of the boolit exploded in the water leaving a flat nose boolit remnant to continue on its way. This would make a good varment and bigger game boolit. It's what I am aiming for with my 230gr 303 Brit hollow nose boolits. I've changed the shape of the the hollow to give a bit more strength at the base of the hollow to hold the 'mushroom' onto the boolit. If yours was deilled, the hollow would have had a very weak point at its bollom where the expansion forces would have sheared it off. Try shaping the drill bit to produce a tapered and rounded hollow then do the test again (wearing a raincoat this time) and see what happens. And of course, post the results.;-)

Larry Gibson
02-13-2010, 06:11 PM
What was the diameter of the drill?

Larry Gibson

lwknight
02-13-2010, 06:44 PM
I have had round nose boolits mushroom really well in 44 mag. The alloy was about 40:1
99.5% weight retension and completely turned inside out. The new technology HP bullets are not velocity dependant like standard cast. Commercial pistol JHPs are pure dead soft lead for the most part and the cheaper ones depend on velocity.

I'm not familiar with Universal but, that sounds like a light load. You really need a chronograph and be able to get about 1300 fps or better to make full expansion of a 20:1 cast bullet IME anyway.

rob45
02-13-2010, 07:33 PM
What was the diameter of the drill?

Larry Gibson

An excellent question that should be answered before speculating further.
From what I can determine, the drill used was too large in diameter for this application. But then again, he stated a depth of 6/16, which is .375" deep. If indeed that was the depth, the width of the cavity would have been very small to effect that displacement (35 grns). However, the photos indicate a cavity that was too wide rather than too deep.

The alloy used was not at fault. Such a conclusion is supported by the fact that 20-1 alloy has been successfully used at these velocities in cast HP for over a hundred years.
Here's something to think about: A weight loss of only 10 grains was reported; that's 95% weight retention, guys!
Using my failing eyes, I will still look at the photo and venture to say that the nose was not lost, but simply displaced. The body of the fired bullet shows no visible rifling, and I bet if one were to stick the trusty caliper to it, the bullet is larger in diameter. So the best conclusion I can reach is that the nose simply folded back over the body; after all, no tremendous weight loss occurred.

A hollowpoint that displaces 35 grains in a 41 caliber is on the large side to say the least. I would make the cavity smaller and retest.

Shiloh
02-13-2010, 10:24 PM
it may have swaged closed upon impact. Give more info on size, depth and other parts of the procedure.

Shiloh

fredj338
02-13-2010, 11:02 PM
Is it possible that you were to close and bulltet was still at to high of FPS to catch proper expansion? Surly you were to close for the bullet to tumble. Maybe your alloy was a bit on the hard side, do u have a brinell tester?
HP bullets tend to expand w/ more vel. not less. Too much vel. can cause the nose to fragment. I suspect your HP needs to be wider, not deeper. In fact, my on test show the deeper the HP the greater the chance of fragmenting the nose. A wide, medium to shallow cup point provides better high vel. expansion. A 25-1 alloy works to 1250fps for me. These are all from saturated phone books.

http://img.photobucket.com/albums/v703/fredj338/th_452-268-1K.jpg (http://smg.photobucket.com/albums/v703/fredj338/?action=view&current=452-268-1K.jpg)http://img.photobucket.com/albums/v703/fredj338/th_9mm-136-1200.jpg (http://smg.photobucket.com/albums/v703/fredj338/?action=view&current=9mm-136-1200.jpg)http://img.photobucket.com/albums/v703/fredj338/th_44-272-1K.jpg (http://smg.photobucket.com/albums/v703/fredj338/?action=view&current=44-272-1K.jpg)

dubber123
02-14-2010, 12:59 AM
Something else to try, is pre plug the cavity with Paraffin, or any kind of stick boolit lube. HP's are dependant on hydraulic pressure to work. If they become plugged with a "non hydraulic" material, Ie. clothing, wood, etc, they don't work. They don't work if the nose folds over preventing any liquid from entering either. Pre plugging with something that goes hydraulic under pressure assures expansion. Some of the "new" high tech boolits use this very old idea. http://i254.photobucket.com/albums/hh83/dubber123/IMG_3149.jpg Pre plugged with LBT Blue Soft lube.

JesterGrin_1
02-14-2010, 01:06 AM
Something else to try, is pre plug the cavity with Paraffin, or any kind of stick boolit lube. HP's are dependant on hydraulic pressure to work. If they become plugged with a "non hydraulic" material, Ie. clothing, wood, etc, they don't work. They don't work if the nose folds over preventing any liquid from entering either. Pre plugging with something that goes hydraulic under pressure assures expansion. Some of the "new" high tech boolits use this very old idea. http://i254.photobucket.com/albums/hh83/dubber123/IMG_3149.jpg Pre plugged with LBT Blue Soft lube.

You know Dubber when I was very young I remember a person that told me to just melt candle wax into the end of a HP. As he said it made the bullet fly straighter and gave better penatration and expansion than to just leave the HP alone.

But I as of yet have not hunted with any kind of an HP thus far.

357maximum
02-14-2010, 01:31 AM
How to make a HP grenade on game even when you do not intentionally want to.


1. Insert your head up your rear and visually inspect your colon.

2. cast a 358156 out of soft pb/Sn alloy with a large and deep HP

3. Launch said boolit as fast as you can in a 357mag revolver

4. shoot a deer at 40 yards and strike it too low near the back edge of the shoulder blade.


I did it all wrong and the freezer paid for it in less venison. HP's can be a lesson in and of themselves. I am now of the shallow/wide HP train of thought if I were to do the HP thing again.

I am more inclined to just anneal the nose of a solid if I ever need to initiate expansion for some reason.....it always works and there is no chance of mucking it up.........I am sure HP's work for alot of fellas, but I am not willing to learn their quirks when a 50/50 ww/pure boolit does not require all the tiptoeing. In all honesty and fairness another big reason I am not too keen on HP's is that I simply hate casting them..that is all on me but I am not apologetic about it.

Buckshot
02-14-2010, 03:25 AM
"Shot into 2 liter water filled bottle backed by 8 in tight newpaper. "

............If that 'tight' newspaper was dry it'd almost be a solid. Completely soaked newspaper gives a better rendition of flesh (which I assume you're interested in). That 3" penetration could easily have doubled.

..............Buckshot

imashooter2
02-14-2010, 08:22 AM
Hollow point, blah, blah, blah...

Why in the world are you shooting in your crawl space?

WHITETAIL
02-14-2010, 08:41 AM
Keep at it!
Thats what making your own
lets you try all kinds of things.:Fire:

44man
02-14-2010, 10:25 AM
Tried a Lee 240 g 41 mag swc hollow pointd by drilling to 205 g deep hollow point. Load 7.5 g Universal .Shot into 2 liter water filled bottle backed bu 8 in tight newpaper. RESULTS: Wife watched as water soaked me ( I was about 5 yrds away in my crawl space. The bullet went straight thur the bottle impacted news paper(dry) It penetrated about 3 inches. To my surprise no mushroom.(see pics) Alloy was 20-1. The bullet lost 10 grains in weight.I beleive the bullet collapsed on its self. Maybe the HP was to deep (6/16) Killed the soda bottle though Rick
HMMMMM, how do you know what happened to the 20 to 1 boolit in the throats and at the forcing cone? Maybe it slumped the hollow point away.
This is a similar alloy. Notice it has changed the Keith to an LBT and wiped out the grease grooves, it also skidded. Weaken the nose with a hollow point and just what did you shoot out of the barrel?

Gohon
02-14-2010, 10:50 AM
Can't remember where I read it nor who the author was but I believe it was Brian Pearce or maybe it was Larry Gibson now that I think about it. Anyway, this person was looking for a good hollow point hunting load for a revolver I believe and after extensive testing he came to the following conclusions with home cast loads. BHN of the alloy should be something like 10-13. The depth of the hollow point should never exceed 1/3 the length of the nose, and last was speed at point of impact should be between 1000 fps and 1200 fps but no more than 1800 from a rifle. He started out using the Forster Hollow pointer using a 1/8 inch drill bit and went to hollow point moulds. I'm sure I have some of these figures off a little but the main thing that stuck in my mind was anything more than 1/3 depth of the nose portion usually caused the nose to implode rather than expand and anything harder than 13 bhn usually resulted in no expansion at all.

Bloodman14
02-14-2010, 12:16 PM
For hunting purposes, pack the cavity with plain ol' lard; that will give you your hydraulic effect, and it's edible.

303Guy
02-14-2010, 12:51 PM
I am more inclined to just anneal the nose of a solid if I ever need to initiate expansion for some reason.....How does one anneal the nose - or even the whole boolit?

I ask for two reasons; one being to initiate expansion at pistol velocities (from a rifle - Pig Gun project) and the other is to get the nose portion of a 'longer than pistol' boolit to upset sufficiently to 'lose' the paper patch (also Pig Gun project).

I've been experimenting with hollow points and flat noses. I've also tried the trick of filling the cavity with boolit lube - since I was nose dipping the loaded boolit into molten waxy-lube on a smooth sided boolit.

I did a simple test using the same boolit loaded to different velocies by vertue of increased powder charges, stopping when the pressure got to be 'enough'. Test medium was soft, fine, sea sand (which is high in shell content). Alloy is some lead sheeting I melted down and is a lot 'harder' than lead pipe. The hollow was like two-thirds the diameter of the boolit and as deep (just under ¼"). Boolit is a 230gr HN 31 cal.

http://i388.photobucket.com/albums/oo327/303Guy/MVC-574F.jpg

Weight rention is around 99.5% ~ 99.9%, so the rim of the hollow is not being blown off on impact and sand is pretty aggressive.

I have compared flat nose to hollow point (the flat nose being heavier) and the expansion of the flat nose is considerably less but without a chrono I cannot compare at identical velocity.

1Shirt
02-14-2010, 01:49 PM
303Guy, I read and think highly of Paco Kelly's stuff, and have used his method of softening nose only on blts. Suggest you pull up and read Paco on this subject. I have done 30, 22, and heavy 45's by his method. I stand the blt in water up to about 3/4 the length of the blt for both hp and non hp blts. Have done this with checked/sized/lubed blts, as well as non sized and lubed blts. I use a propane torch with a fine blue white flame to heat the nose until it it ready to slump then tip the blt into the water. Thats it! You have to work at it a bit to keep from screwing up and melting the nose, and this is particularly true of the little hp's. (doesn't take very long)! Lilke a lot of other things associated with handloading, it is a trial an error process, and there will always be error. Have also screwed around with big 450/500 gr 45 cal blts with a piece of thin alum foil between the nose half of the mold. Produces an interesting blt (have never tried nose softening them however. Only shot a few of these things at fence post size wood with 45/70, and would not want to shoot them at a meat animal. Also swaged a copper plated bb into the HP of a 375 HP(260 gr) as I was sizing/lubing it for 375 H&H. Good looking blt., but have not shot any to test performance and expansion. They stayed well under 3" at 100 however
at chronoed vols in excess of 1850 fps. These were about 18BH, (probably a little to hard) The recovered bases in semi clay like dirt behind the targed showed that the noses had gone with the wind, but that the bases probably 60% remained, and most still had their gas checks. Anyhow, might give you something to think about and possibly play with. Good luck. I never met an Auzzie that I didn't like, and I enjoy all of what the Auzzies on this forum post.
1Shirt!coffeecom

1Shirt
02-14-2010, 01:54 PM
303Guy, Hope I didn't offend you as I just noticed that you are not an Auzzie but a New Zelander, and guess I kind of lumped you in that part of the world together. What I said about Auzzies also applies to New Zelanders. Have not met as many of you folks as I have Auzzies, but liked all that I have met. (Maybe a dozen or so!)
1Shirt!:coffee:

fredj338
02-14-2010, 02:11 PM
"Shot into 2 liter water filled bottle backed by 8 in tight newpaper. "

............If that 'tight' newspaper was dry it'd almost be a solid. Completely soaked newspaper gives a better rendition of flesh (which I assume you're interested in). That 3" penetration could easily have doubled.

..............Buckshot
I find max expansion happens in the first 4"-6" of penetration. The bullet either expands or doesn't & the 8" of dry paper caught the bullet &/or deformed the rest of the HP. You need wetmushy paper to capture the true expanded shape. All water works too, but water is actually pretty hard on impact & can deform a bullet that will NOT expand in wetpack.

HMMMMM, how do you know what happened to the 20 to 1 boolit in the throats and at the forcing cone? Maybe it slumped the hollow point away.
This is a similar alloy. Notice it has changed the Keith to an LBT and wiped out the grease grooves, it also skidded. Weaken the nose with a hollow point and just what did you shoot out of the barrel?
SOrry, I can't buy this. I've recovered dozens of solid LSWC of varying alloys & none have ever "changed shape".

fredj338
02-14-2010, 02:16 PM
I stand the blt in water up to about 3/4 the length of the blt for both hp and non hp blts. Have done this with checked/sized/lubed blts, as well as non sized and lubed blts. I use a propane torch with a fine blue white flame to heat the nose until it it ready to slump then tip the blt into the water. Thats it!
Wouldn't standing the bullet in water upto the base of the nose, then heating in say a 400deg oven, then let them just cool on there own soften the nose & leave the body unchanged? I'll have to try that.

44man
02-14-2010, 02:26 PM
Heating the nose just short of slumping and tipping them into the water just makes the nose harder. Let them cool by themselves.

imashooter2
02-14-2010, 06:08 PM
I still want to know why in the world the man is shooting in his crawl space.:shock:

fredj338
02-14-2010, 08:50 PM
Heating the nose just short of slumping and tipping them into the water just makes the nose harder. Let them cool by themselves.
That's what I thought?[smilie=s:

rob45
02-14-2010, 08:58 PM
Heating the nose just short of slumping and tipping them into the water just makes the nose harder. Let them cool by themselves.

I will agree with that.

The (cold) water is simply used to limit heat transfer on the body of the hardened bullet so that you don't anneal the body.

Before annealing the nose, the entire bullet is already hard.
The goal is to keep the body hard and then soften the nose.
If you tip the hot nose into the water, you have heat-treated and quenched, thereby defeating the original goal of having a hard body/soft nose.

303Guy
02-15-2010, 01:31 AM
I never met an Auzzie that I didn't like, and I enjoy all of what the Auzzies on this forum post.Mmmmm.... Now that you mention it, nor have I. I've only met a few in person and a few more on this and other shooting sights. They're kinda diffrent.:Fire: I worked with a young Ozzie fella. Nice chap. I called him 'Crocodile' and said he was NZ's greatest crocodile hunter. Someone said there weren't any crocks in NZ! I replied, "I rest my case".:mrgreen:


... standing the bullet in water upto the base of the nose, then heating in say a 400deg oven ...That would boil off the water![smilie=1:

However, how hard would it be to heat a batch of boolits in an oven then dipping just the base into water? Some sort of holder device with the noses up and shielded from the water dip below? My trouble so far is I have failed to anneal a boolit by heating it and allowing it to cool slowly. I have homoginized them though and that in itself may not be a bad thing.

44Man

You say that boolit in the pic skidded? From the pic is doesn't look like it skidded. (You can see it way better in your fingers where you can turn it and hold it to the light). I have never had a boolit skid (that I know of). Nearly skid yes, where the groove impression is way smaller than the groove itself.

lwknight
02-15-2010, 03:09 AM
I still want to know why in the world the man is shooting in his crawl space.:shock:

I'm wondering if the snow was too deep to actually go outside.

imashooter2
02-15-2010, 08:25 AM
I'm right here where we got the worst of it and I sure as hell would wade through the 36 inch deep snow before I shot in the crawl space under my house.

Especially since he said he only got 5 yards away.

44man
02-15-2010, 09:10 AM
SOrry, I can't buy this. I've recovered dozens of solid LSWC of varying alloys & none have ever "changed shape".
I can't take credit for this picture. It is out of an old Handloader from an article by H. G. Anderson. The date is 1988. It is a .44, 263 gr boolit that started at .763" and recovered length is .720". It is a gas checked boolit too.
303guy, look at the width of the land marks on the front band, they are about 1-1/2 times the marks on the base.
Now look at my 420 gr, .475 boolit on the right. It skidded past the base, opened gas channels and leaded my gun. This is water dropped WW metal.
The left boolit is from my .45 and it was cast from a harder alloy.

outdoorfan
02-15-2010, 09:58 AM
However, how hard would it be to heat a batch of boolits in an oven then dipping just the base into water? Some sort of holder device with the noses up and shielded from the water dip below? My trouble so far is I have failed to anneal a boolit by heating it and allowing it to cool slowly. I have homoginized them though and that in itself may not be a bad thing.




http://www.beartoothbullets.com/tech_notes/archive_tech_notes.htm/35