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DGV
05-29-2009, 01:21 PM
Is there any difference in quality of bullets that are frosted metilurgically (spelling) or otherwise in using for Big Game or even just target practice. Any and all comments are welcome.

bedwards
05-29-2009, 01:40 PM
I honestly don't think so, but someone will come along soon and correct me!


be

Calamity Jake
05-29-2009, 02:04 PM
Heavy frosting is bad, it causes the boolit to be small for cal. Makes them grainy with the antimony crystles on the outside and possibley brittle.
An evenly frosted(dull gray color) is good.
Spotty frosting means these areas will be small for cal.

M2¢

BPCR Bill
05-29-2009, 02:21 PM
Frosting is caused by a mould that is too hot, and is usually accompanied by "finning" into the block vents, but not always. If you are casting with one mould block and going too fast, frosting is sure to happen. Check the temperature of your melt occasionally and try to cast with a slower cadence. Casting with two moulds during a session is something I do. If you let the amount of alloy get too low in the pot it's temperature will go up. You'll have variances in boolit diameter as well as weights. I shoot BPCR competitively and am pretty anal about the quality of my castings for target work. Ditto for big game hunting. Deer and Elk have x-rings too! If you're plinking on wild mean beer cans, not a big deal I guess.

Regards,
Bill

leftiye
05-29-2009, 02:38 PM
Heavy frosting is caused by a mold that is too hot. Light uniform frosting is caused by a mold that is just right. Finning is caused by mold halves that aren't closed. Whiskering is caused by pressure, a good alloy, and a mold that is not too cold.

454PB
05-29-2009, 02:40 PM
I usually throw non-frosted boolits back in the pot. I strive for a light frosted appearance and don't consider the first shiney boolits up to full quality. Try this sometime......set the first shiney boolits aside and then later weigh and measure them for comparison to the frosted ones.

Down South
05-29-2009, 03:30 PM
I like a light uniform frost. The shiny boolits usually are not filled out correctly (round edges on the drive bands in places and wrinkles). I discard the non frosted boolits back to the pot.

Slow Elk 45/70
05-29-2009, 03:35 PM
+1 for lite frost, dull gray , shiny -back to melt.

jonk
05-29-2009, 04:08 PM
I also like light frosting. Even heavy frosting. Any frosting, especially chocolate.

But really, I find it doesn't hurt anything. In fact it helps fill out to have it hot. It may or may not shrink the size of the bullet but I've not had any issues.

The only non-frosted bullets I get reliably good fill out with are pure lead and then only when the lead is hot anyhow- just no antimony to frost. I probably have some zinc contamination and this is part of the reason but that's ok.

runfiverun
05-29-2009, 08:24 PM
i think there is a difference between grey and frosted.
to me frosted is white grey is good.
i have a mold that once it is up to temp will throw beautiful grey boolits unless i fill it too slowly then it will frost up [white] the front driving band and round it off.

lead Foot
05-29-2009, 08:49 PM
We don't get any frosting here it doesn't get cold enough [smilie=1: But I know what you meant. Living in the bush and at the end of the line the power is not good enough to get the pot hot enough. I did get frosting with a lee mould once and had no problems with it just shot the same. I do agree with running two moulds at once.
Lead foot;

jdgabbard
05-29-2009, 08:56 PM
If their not frosty, I drop them back into the pot for recasting.

303Guy
05-29-2009, 08:58 PM
I get a fine, light grey frosting. Sometimes I get course frosting. Recovered course frosted boolits show a strength irregulatity and swell along the frosting boundries. I have a mold I designed specifically to control the cooling rate along it's length. These boolits expand up to the faster cooled section of the boolit.

http://i388.photobucket.com/albums/oo327/303Guy/MVC-888F.jpg
http://i388.photobucket.com/albums/oo327/303Guy/MVC-905F.jpg
http://i388.photobucket.com/albums/oo327/303Guy/MVC-010F.jpg

WHITETAIL
05-30-2009, 06:08 AM
If frosting is good enough for Tony the Tiger it's good enough for me!:castmine:

Bret4207
05-30-2009, 08:19 AM
Heavy frosting is caused by a mold that is too hot. Light uniform frosting is caused by a mold that is just right. Finning is caused by mold halves that aren't closed. Whiskering is caused by pressure, a good alloy, and a mold that is not too cold.

Very well said. I'll add that frosted boolits expand just like non-frosted as far as I can tell.

Bob Krack
05-30-2009, 09:28 AM
What I wanna know is - where can I get a mould for this boolit? pretty low BC but I would bet it gets great expansion and would hold all the lube you could possibly want!

303Guy
05-30-2009, 11:30 PM
.... would hold all the lube you could possibly want!
Hee hee!:mrgreen:

I have tried knurling the boolit and would you believe the knurls are still there after firing! Actually, the second fired boolit above, was knurled up to the neck.

One boolit I tried had flame cutting which started leading in the bore - what a struggle to get all of it out! There was a patch that just kept on re-leading!

This was part of the first batch of seven boolits I range tested. MV around 1900fps. No leading. These were 220gr slow cooled WW.
http://i388.photobucket.com/albums/oo327/303Guy/MVC-457F_edited.jpg

They were all frosted.
http://i388.photobucket.com/albums/oo327/303Guy/MVC-331F_edited.jpg
I think this pic shows the frosting. They were from a different mold which didn't have as much differencial cooling as the one in the pic above.

It seems that docone31 has the mold design sorted. Perhaps someone could make a few for the fellows?

Whitespider
05-31-2009, 09:36 AM
I like bright, shiny boolits. On a good day, if I can get every thing just right, alloy, alloy temperature, mold temperature, timing, etc., my boolits are mirror bright with an occasional one just barely starting to "gray" up a bit. When I'm having one of those "good" days it's hard to shut the pot down. I also have the occasional "bad" day when I can't seem to pour anything, go figure.

Bill*
05-31-2009, 10:37 AM
Just thinking out loud....[smilie=1: , would a frost finish hold more tumble lube??? Seems to me it would? (and I've never been wrong, except for usually)

243winxb
05-31-2009, 11:39 AM
Frosted bullets are generally a sign that the mold is too hot. Let the mold cool for minute or two with the blocks open and sprue plate open. You may also want to lower the temperature of the pot. Once you reach a spot where you are seeing wrinkled bullets, you have gone too far. Slightly adjust back to a hotter temperature and you should have achieved the prime temperature setting for your pot.

Frosted bullets cause no problem when shooting so it is not necessary to discard them back into the pot. In fact, frosted bullets tend to cause the Liquid Alox to adhere even better which is very desirable, especially for bullets meant to be shot at higher velocities. http://www.leeprecision.com/cgi/faq/index.cgi

montana_charlie
05-31-2009, 01:15 PM
The goals of the many members of this forum are as varied as the alloys they use.
You see 'revolver guys' replying to 'rifle' discussions, and their remarks (often) don't compute because the environments in the two types of firearm are so different. Different goals make for different ideas in many other areas, too...including frosted bullets.

Many (perhaps most) of the members here use antimony in their alloys. Most of those also believe that anything more than a smidgen of tin content is a waste.
They 'say' they add the tin to enhance mould fillout, but they actually 'use' heat to accomplish that. Heat makes frost. If you need heat to get fillout, you have to accept frost.
It gets to a point where, if there is no frost, incomplete fillout is assumed.

Switch over to those members who meet their goals with lead/tin alloys. They get proper fillout thanks to the tin content, and can produce high-quality bullets well below the frosting temperature.

So, if a revolver guy replies to a thread that is discussing how far into the lands a bullet should sit, you know he is out of his area of expertise.
You should make a similar judgement when receiving advice concerning frosted bullets.

A hard-bullet, high-speed guy will say one thing...and guy shooting rainbow trajectories with 500 grainers will say something else.

Pick the advice that matches your goal.

CM

dwtim
05-31-2009, 01:39 PM
I personally go by base fill-out when searching for the right bullet. I've never had a bullet so frosted that it was under-size, but I do not like handling frosted bullets. If you look at the surface under a microscope, the frosting is caused by little crystals that stick up like spines. Whenever you handle a frosted bullet or ingot, those metal spines stick in your skin, and do not wash out without some good scrubbing.

A little frosting is unavoidable, especially with aluminum molds it seems, so I prefer to pan lube so that a little excess is left on the surface after I put them through a Lee sizing die. I spread this excess evenly over the bullet and it makes it so I don't have to worry about getting bits of metal in my skin, because it knocks down the spines and coats the surface with wax. This makes it so I can handle my ammo at the range without gloves, and it also keeps the surface from oxidizing and getting ugly.

If you find you cannot have a bullet that does not get frosted, try waiting until after Memorial Day to plant them. And never attempt to transplant a gun with rust that is blossoming.


EDIT:

I have tested Sn content from 1 to 2.6 percent, and found that the latter makes no difference in fill-out with most of my bullet styles. (To put this in perspective, I shoot common medium and large bore pistol calibers and .30 cal rifle, and I ladle-cast.) The best method I have found is to note the exact temperature of the melt which makes good bullets, and use the thermometer to hold it throughout the session. Then I experimented with the count to establish the rhythm.

I suppose that I could make life easier by using an alloy that could be traded as currency, but I can usually find a good balance by upping the temp and pouring fast. With a small adjustment of the casting rhythm, I usually find that I can maintain fill-out and keep the frosting to a minimum.

Everyone has their reasons, but I use a lot of range scrap alloy to keep my costs down. I have a small cache of pure, 20:1 and 50:50, so I see no use in wasting it on 45 ACP or 303 fodder when it means I would starve my muzzleloaders.