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tking308
02-12-2014, 02:15 PM
I decided to see how much my .357 mag load would expand so I shot it through 5, 1gallon jugs of water. This is a Lee 358-158swc cast of COWW +2%tin water dropped. After passing through the water and nearly passing through the 1/2" plywood behind it, ZERO expansion! Darn thing looks new. I chronographed this load at 1395 fps. I was hoping to use this as a deer load but I'd like a little expansion. Should I try air cooled? SOWW?

tking308
02-12-2014, 02:23 PM
96593
Looking at the boolit I realize there isn't any sign of land and grooves. Back of boolit is slick ( gas cutting?)

aspangler
02-12-2014, 02:23 PM
Try air cooled 50-50 pure/ww.

richhodg66
02-12-2014, 02:39 PM
Agreed. WWs actually water quench pretty hard. Obviously, penetration shouldn't be a problem. Soften the alloy and go hunting.

Blammer
02-12-2014, 03:08 PM
no not gas cutting, water cutting. :)

use the same alloy just air cool, you should get some expansion. May need to slow it down a tad, won't hurt a thing.

not the greatest picture but here is alittle expansion out of my 357mag rifle into water jugs.


http://i54.photobucket.com/albums/g81/blammer8mm/Cast%20boolits/DSCN5973.jpg (http://s54.photobucket.com/user/blammer8mm/media/Cast%20boolits/DSCN5973.jpg.html)

Blammer
02-12-2014, 03:09 PM
top view

http://i54.photobucket.com/albums/g81/blammer8mm/Cast%20boolits/DSCN5975.jpg (http://s54.photobucket.com/user/blammer8mm/media/Cast%20boolits/DSCN5975.jpg.html)

Blammer
02-12-2014, 03:10 PM
yep also a lee 358 158, this just air cooled WW's only.

Blammer
02-12-2014, 03:11 PM
and the video
http://i54.photobucket.com/albums/g81/blammer8mm/Video/th_DSCN5791.jpg (http://i54.photobucket.com/albums/g81/blammer8mm/Video/DSCN5791.mp4)

swheeler
02-12-2014, 03:57 PM
and the video
http://i54.photobucket.com/albums/g81/blammer8mm/Video/th_DSCN5791.jpg (http://i54.photobucket.com/albums/g81/blammer8mm/Video/DSCN5791.mp4)

Hope the camera was water proof:)

NVScouter
02-12-2014, 04:27 PM
Looks like an air cavity in the picture too.

Bullshop
02-12-2014, 04:49 PM
Simple rule of thumb to determine minimum velocity for expansion. BHN x 100 = velocity
Water quenched coww can harden up to nearly BHN-25 depending on how hot they were when they hit the quench.
Lets say yours were about BHN-20 when you fired them so they would require a """ minimum impact """ velocity not muzzle velocity of 2000 fps to expect expansion.

357maximum
02-12-2014, 05:42 PM
Try air cooled 50-50 pure/ww.

WINNER WINNER CHICKEN DINNER :lol:

Bullshop
02-12-2014, 06:16 PM
Air cooled 50/50 will test about what BHN? I will venture a guess at about 9 or less. Apply the formula BHN-9 x 100 = 900 fps impact velocity for expansion. Sound about right.

Wolfer
02-12-2014, 06:22 PM
I'd guess that formula to be good. I shoot a 10 bhn right at 1000 fps from my 45 colt and even though their HP the ones I've recovered are mushroomed well below the bottom of the cavity. Woody

Edit
Mine are 1 WW - 2 lead for bhn of 10 but in my defense a big majority of my WWs were several years old and tested at 16 bhn. My newer WWs are probably not much harder than 10 if that hard.

dubber123
02-12-2014, 06:36 PM
Air cooled 50/50 will test about what BHN? I will venture a guess at about 9 or less. Apply the formula BHN-9 x 100 = 900 fps impact velocity for expansion. Sound about right.


Good guess. My 50/50 tests at 9 with an LBT tester. Never tried it with a solid, but excellent repeatable expansion at 850 fps. in HP form.

http://i254.photobucket.com/albums/hh83/dubber123/IMG_3149.jpg (http://s254.photobucket.com/user/dubber123/media/IMG_3149.jpg.html)

uncle joe
02-12-2014, 06:39 PM
I can attest that 50/50 will expand very well with a 44 mag hollow pointed, they look great.

tking308
02-12-2014, 07:07 PM
Sounds like I need to aquire more pure lead. I'm gonna see what air cooled will do too.

singleshot
02-12-2014, 07:39 PM
Looks like an air cavity in the picture too.

I was thinking the exact same thing.

DLCTEX
02-12-2014, 07:51 PM
Me too^^^

leadman
02-12-2014, 09:20 PM
You could stand these water quenched boolits in some water to a point you want it to expand to and then heat the nose with a propane torch to anneal them. This would let the nose expand and still have a hard rear to push thru.

tking308
02-12-2014, 10:38 PM
Looks like an air cavity in the picture too.

Enlighten me about air cavities.. I'm a noob. My guess is you're saying that when I poured into the mold I did something to cause an air pocket in the boolit. If that's the case, what might I have done?
When I get home, I'm going to look closely at the plywood this boolit hit after going through the water jugs. It hit broadside (keyhole) and went about half way through. I saw the mark on the boolit and for some reason associated it with an 18ga staple head from the air stapler I recently got.

siamese4570
02-12-2014, 11:45 PM
If it helps any, I shoot the 330 gr gould hp in my 45-70 at 1300 fps. I use straight stick on ww with no leading and it expands like a marshmellow.
siamese4570

Socal147
02-13-2014, 12:09 AM
BHN x 100 = velocity
Good info

Thanks

BPrezPB
02-13-2014, 02:14 AM
Enlighten me about air cavities.. I'm a noob. My guess is you're saying that when I poured into the mold I did something to cause an air pocket in the boolit. If that's the case, what might I have done?
When I get home, I'm going to look closely at the plywood this boolit hit after going through the water jugs. It hit broadside (keyhole) and went about half way through. I saw the mark on the boolit and for some reason associated it with an 18ga staple head from the air stapler I recently got.

Would weighing your boolits detect an air cavity? I like to weigh mine to sort imperfections, or so I thought

NVScouter
02-13-2014, 04:12 AM
Would weighing your boolits detect an air cavity? I like to weigh mine to sort imperfections, or so I thought

Exactly. I used to get them when I bottom poured. I changed to ladle pour and a use a thermometer now and I'm good.

Weighing them is only real way to spot most of them. It could be just a nick but I'd look again. Has more to do with accuracy then anything.

Bullshop
02-13-2014, 12:02 PM
Another way to aid expansion with a hollow point is if for some reason you feel the impact velocity may be too low for the alloy being used. Fill the hollow point cavity with boolit lube.
The hydraulic effect will aid expansion when impact velocity is below minimum required for expansion of unfilled nose cavity.
It works.

jmort
02-13-2014, 12:25 PM
Water is a tough test medium, very hard on Boolits/bullets. If water don't open it up the it will not expand in the real world. Further, just because it expands in water does not mean it will expand in the real world. Regardless, shooting Boolits in water is fun.

taco650
02-13-2014, 01:38 PM
Sounds like I need to aquire more pure lead. I'm gonna see what air cooled will do too.

I shoot at an outdoor public range and have days off during the week. I go there and scrounge used bullets when nobody else is present. They're just laying on the ground and I just pic them up, take them home, clean off the dirt then melt them down and make ingots and later mix that with my WW lead. I'll pick up jacketed as well as cast. Its more work to do this than buying pre-made ingots but its cheap and I enjoy the recycling aspect, YMMV.

Wolfer
02-13-2014, 08:21 PM
Quote, shooting boolits in water is fun.

Well sir that can be a matter of opinion. I've told this story before but here it is again. When I first started casting for my 45 colt I'd heard about gas cutting but had never seen it. Wondering what a fired at full power boolit looked like I devised a plan that I thought was better than shooting into the EZ pool.
I took a 10' stick of 4" PVC and duct taped the end up good. Propped it up on my baler tongue and filled it with water. I backed off a few feet and lined up with the pipe. When I touched it off there was a 4" stream of water fire hosed out of the pipe. Washed my hat off my head and the only dry spot I had was a little strip down the middle of my back.

I did have a good boolit to look at though. I found it just outside the pipe, it went thru the 10' of water and hit a rock hard enough to ding the nose. I was really glad I didn't shoot into the little woman's pool. It was only 4' deep.

I believe member oneshot can tell a similar story if you can get him to. Woody

waksupi
02-13-2014, 09:01 PM
It is always gratifying to see another person learn about physics! :wink:

dubber123
02-13-2014, 09:53 PM
Another way to aid expansion with a hollow point is if for some reason you feel the impact velocity may be too low for the alloy being used. Fill the hollow point cavity with boolit lube.
The hydraulic effect will aid expansion when impact velocity is below minimum required for expansion of unfilled nose cavity.
It works.

Kinda like mine in post #15.:wink: Pre-plugged with blue boolit lube. Wood, multiple layers of denim, doesn't matter, they all look the same.

singleshot
02-14-2014, 10:24 AM
Enlighten me about air cavities.. I'm a noob. My guess is you're saying that when I poured into the mold I did something to cause an air pocket in the boolit. If that's the case, what might I have done?
When I get home, I'm going to look closely at the plywood this boolit hit after going through the water jugs. It hit broadside (keyhole) and went about half way through. I saw the mark on the boolit and for some reason associated it with an 18ga staple head from the air stapler I recently got.

Here's the facts:

#1 - If air can't escape from the mold as fast as lead is coming into it, you'll get an air pocket
#2 - See #1.

So how do you mitigate this?

#1 - Make sure your mold has functional air vent grooves, if it doesn't you can create some, I think there's several posts around here about how to do that
#2 - Make sure the lead flow is slow enough to facilitate fill-out. On a bottom pour mold, you often need to match the flow to the mold to ensure it doesn't fill too quickly.
#3 - Make sure your mold is hot enough that the lead doesn't harden the instant it hits the mold. This will allow time for the air to escape and ensure mold fill-out.

Hope this helps.

tking308
02-14-2014, 10:29 AM
Thanks Singleshot. That helps a lot.

singleshot
02-14-2014, 10:34 AM
Thanks Singleshot. That helps a lot.

No problem. I edited the post slightly since there's really only 1 cause of air pockets and I don't think anyone really needed me to be redundant, but the fixes are the same. :-)

NVScouter
02-14-2014, 10:51 AM
Thanks Singleshot. That helps a lot.

When I ladel pour now I overpour quite a bit. This helps force out air, and keeps the mold hotter. When I was bottom pouring I just added enough sprue to cover the pour hole. My accuracy has improved too. I didnt notice anything on handgun boolits but this has helped my rifle boolits A TON!

kevmc
02-14-2014, 01:08 PM
"Well sir that can be a matter of opinion. I've told this story before but here it is again. When I first started casting for my 45 colt I'd heard about gas cutting but had never seen it. Wondering what a fired at full power boolit looked like I devised a plan that I thought was better than shooting into the EZ pool.
I took a 10' stick of 4" PVC and duct taped the end up good. Propped it up on my baler tongue and filled it with water. I backed off a few feet and lined up with the pipe. When I touched it off there was a 4" stream of water fire hosed out of the pipe. Washed my hat off my head and the only dry spot I had was a little strip down the middle of my back"

LOL That there is Funny, I don't care who you are!!!!
I probably would have first yelled........
HEY Y'ALL, WATCH THIS!!!!

gray wolf
02-24-2014, 12:10 AM
LOL That there is Funny, I don't care who you are!!!!
I probably would have first yelled........
HEY Y'ALL, WATCH THIS!!!!
Then I would have said: ( Hey!! Yall wanna give it a go )

fouronesix
02-24-2014, 12:46 PM
I decided to see how much my .357 mag load would expand so I shot it through 5, 1gallon jugs of water. This is a Lee 358-158swc cast of COWW +2%tin water dropped. After passing through the water and nearly passing through the 1/2" plywood behind it, ZERO expansion! Darn thing looks new. I chronographed this load at 1395 fps. I was hoping to use this as a deer load but I'd like a little expansion. Should I try air cooled? SOWW?

Really not surprising at all about no expansion. Instead of an unknown alloy recipe, it would be best to use a common frame of reference like BHN. The recovered bullet shows some odd loss from the impact and travel (pockets of missing material!). I do see land and groove marks on the shank and it's impossible to tell about gas cutting around the base since going through the jugs, water and wood is going to smear the perimeter of the bullet anyway.

At any normal impact velocity of the 357, you might look more at a very small flattening of the nose (not the textbook, half shank mushroom- common to higher velocity controlled expansion bullets) as being the norm to expect. If you get to the point of designing a bullet for full expansion at those modest impact velocities, you may run into the unpredictable problem of poor penetration on deer size game. Better to plan accordingly for top accuracy, bullet placement and reliable penetration instead of focusing on expansion.