Frosted Bullets?

[DBrown]

My 9mm bullets were coming out nice and shiny and them mid way thru casting they started looking frosted. The molding process seemed to be working the best when they were frosting.
Should I shoot them?
What should I do to avoid them?

[mastercast.com]

Frosted bullets are undersize where they are frosted.

Slow down a little bit , until they are not frosted.

[Saint]

I like my bullets to be a little frosty but I also cast for muzzleloaders which tolerate much more variation in size.

[DLCTEX]

Frosting is removed on the bearing surfaces when sized on my boolits, and the Lee TL boolits shoot just fine in the frosty mode. Dale

[NVcurmudgeon]

Another caster who prefers frosty boolits here. That is if they are frosted all over, it is usually associated with excellent fillout. If there is frost just on one band it can be "sunken band syndrome" which does make the boolit smaller at that place.

[longbow]

I'm with the guys that like frosty boolits. I always find I get better fillout and less problems casting. So far no problems at all shooting them either.

I usually try to keep temperatures just where the frosting starts and is even all over the boolit.

[warf73]

Frosted boolits are fine unless you normaly use the boolits as dropped (no sizing). I run all big boolits frosted I seem to get less variance from boolit to boolit in weight. Most the time a frosted boolit will have great fill out.

If your frosted boolits are the right size or need sizing they should be just fine.

[dubber123]

Unless they measure too small for your use when frosted, I would just pre heat your mould longer. This will get you dropping the frosty boolits right from the start, (consistancy), which is when you say the mould is working the best. I have many moulds, especially the 6 cavity Lees that work a lot smoother when dropping frosty boolits.

[725]

Beem my experience with Lee 6 bangers, too. Just to the point where they start to frost, I get a nice fill out and so far work just fine.

[Bret4207]

In favor of frosting here too.

[Bass Ackward]

Frosted bullets are fine unless you run tin. But I seldom mold without adding tin. So I don't like frosted bullets.

I left a box of shells out in the shootin shanty overnight, so I suppose they are frosted now. But that's the only way I have frosty bullets. :grin:

[bishopgrandpa]

Why is tin a deterrent to frosted bullets? I use tin and find frosted give more consistency and fill out. Mine are not unduly undersized and you can tell I prefer them.

[Leftoverdj]

Uniform light frosting is good. I've never been able to get good bullets any other way from aluminum moulds. Partial frosting or frosting so heavy that it appears granular is bad. Throw them back and try again.

[Pavomesa]

Frosted bullets are a phenomenon that occurs when your mold gets too hot. Casting slower will avoid it. Don't ask me all the metalurgical reasons WHY it happens.

Generally I never worried about it and never suffered because of it. However, I cast enough lead bullets in my days that I got very fast at it and it reached the point if I were casting long thin bullets like say 205 gr 30 caliber, if I kept making bullets after the mold got so hot it was "frosting" the bullets, some would start breaking in half or bending as they came out of the mould.:-? Obviously that sucked.

What I finally started doing when I made bullets was I would cast with several different bullet moulds, some not even the same caliber. When one mould started frosting the bullets, I would set it aside and grab the next. By using several molds I could keep casting and never slow down or have to wait for one to cool off. At the end of the day I would have a bunch of bullets for several calibers.:-D

Another trick is try to keep your molten lead as cool as possible and still pour a good bullet. DON'T OVERHEAT.

[Bass Ackward]

Why is tin a deterrent to frosted bullets? I use tin and find frosted give more consistency and fill out. Mine are not unduly undersized and you can tell I prefer them.



Bishop,

Depends on what you shoot and how far you shoot.

Run an experiment for yourself. Take pure lead and cook the hell out of it. Try to get a frosty bullet. My Lee pot will get close to 1100 degrees and I can't get a frosty bullet. Set some bullets aside to measure later for uniformity.

Then take that same mix and add some antimony only and mold with that and see what temp you get a frosty bullet. (if you can) Set some of those bullets aside to mic.

Then without changing temperature, add a very small amount of tin to that pot at the same temperature and start molding with it. Frosty now? Set some bullets aside. Then add more tin like 1% and set those bullets aside. Frost still look the same? How about when you mic those boolits?

Then ask yourself, what is causing the frosting? We know the diameter of each mix will be different, so what happened to the uniformity of your bullets even though they still look filled out and weight close to the same? Or do they?

See if that test alters your though process in any way. If it doesn't, then you are satisfied with your current results and should continue to hold your opinion.

Irregardless of theory, competition and impact results indicate antimony is more uniform in a mix with the same percentage of tin. As it blends with tin easier and better than with lead itself. That is why equal portions of tin and antimony minimizes the .... brittleness upon impact. It is also why long range competitions don't like to use antimony in preference to lead / tin combos. Even in handguns. What mix did Elmer use for his long range handgun work?

So even though bullets look good and weigh the same, they will be outta balance as different crystalline structure will form unevenly based on cooling rates and you can't control that. But short range target work at paper and cast at normal cast velocities will get enough stabilization for accuracy, you won't notice any difference at all.

I do it for what happens upon impact and for higher velocity work. That's also why some advocate 50/50 WW / pure lead heat treated for these same purposes. Hardness without excess antimony to unbalance the bullet or make it brittle.

So it depends on what you shoot and how you shoot I guess. Tin helps ....balance that out. Unless you over cook it. :grin:

So if you are going to over cook it to frost, why add the tin in anyway?

[Capt Mike]

I was breaking in my new Lee 44 cal molds and the boolets were coming out a little frostier than usual so I googled the problem and ended up here. Just for grins and giggles I decided to water cool a few of the boolets as I had never done that and wanted to see what would happen. I don't know if the boolets will work in better in my Redhawk than the normally cast ones do, but the water cooling took care of the frosting problem!

[waco]

It's good on cake, and boolits too.
Won't hurt anything.
Waco

[Le Loup Solitaire]

Frosting occurs when things are getting a bit hot in the melt and the mold. Casting slower or dropping the temp will usually stop it. It does not usually effect accuracy especially at short to medium ranges.. Some folks just ignore it; some don't like the way it looks. If it bothers you just rotate the loaded bullet head in some #0000 steel wool for a turn or two and it'll be gone. LLS

[longbow]

Hahahahaha! I am with waco! When I read the title that was my first response!

This is a 5 year old thread someone dug up!

Nonetheless, I generally cast with range scrap or wheelweights and a nice even frosting suits me fine. If I am having fillout problems, I just cast faster to keep mould temperature up and maybe increase the melt temperature a bit. Light frosting is usually the result. It works for me.

I don't generally water drop. It is either air cooled or oven heat treated. I figure if I want boolits hard then oven heat treating makes them all the same. I am shooting rifle though not handgun. I find that my .303's with 1:10" twist using heavy boolits do better with oven heat treated boolits than air cooled. Recovered air cooled boolits sometimes show signs of skidding a bit... not stripping, just wider grooves than lands on the boolits which is a hint when they are same width in the bore!

I doubt it will be an issue in a handgun unless you are pushing pressures. Then harder boolits may be better but you want a good fit too because harder boolits may not obturate to seal as well as softer boolits.

My $0.02.

Longbow

[ku4hx]

Frosted boolits and frosted beer mugs ... make both just a little bit better.