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View Full Version : Wrinkled or frosty?



sp0di
06-08-2013, 04:11 PM
Not sure which is better/worse.... They are .225. The wrinkled are 69g and the frosted is 68g - why the difference? All these are water quenched...

Recommendations? I can take some more pics if are needed for additional detail..

.73011

RobS
06-08-2013, 05:05 PM
Frosted is better (to a certain point) better fill out. I can't really tell much from your pic (too far away). Actually if you are casting with WW alloy then a bit of frost is what most of mine look like.

41 mag fan
06-08-2013, 05:09 PM
1gr difference between either is not bad, and in all actuality pretty normal. It's when you get to a spread of 5-10gr that something is wrong.

Marlin Junky
06-08-2013, 05:37 PM
The boolits on the left appear to be formed somewhat better. For best results, the mold temp needs to be about 50-100F below the melt temp of the alloy and the alloy temperature in the pot should be about the same amount above its melting point (or possibly a bit more, depending on your pouring method). Pouring very hot metal (800F+) into a mold that's too cool can produce both strange looking boolits as well as usable ones but consistency for the duration of the casting session won't exist. In other words, start with a hot mold.

MJ

ShooterAZ
06-08-2013, 06:10 PM
Wrinkled boolits go back into the melt pot. Too frosty of a boolit is not so great either, they can even break in half when dropped from the mold. The top ones on the left don't look too bad. Do you have a thermometer? What is your alloy? Usually wrinkled boolits are from too cold of a mold, or oil in the mold. If you don't have a thermometer, get one, and try 700-725 degrees with a pre-heated mold. Then set your casting cadence to get uniform "galvanized" looking boolits with good base & groove fill out.

BubbaJon
06-08-2013, 06:49 PM
As long as they're filled out right frosty is ok. Wrinkled is never ok in my book.

Beagle333
06-08-2013, 06:53 PM
Frosty is better.
I'll allow a little occasional wrinkle as long as it's in the nose and not the driving bands, and also require the dropped size to be at least a hair larger than my sizing die.

sp0di
06-08-2013, 07:00 PM
I was running 800-850... So yeah, going to drop the temp. I do have a thermo :). Just got it...

Shedhunter
06-08-2013, 07:02 PM
I remelt the wrinkled boolits and if they start getting frosty it's time to either slow down your casting speed or turn the pot temp down.

Marlin Junky
06-08-2013, 07:17 PM
I was running 800-850... So yeah, going to drop the temp. I do have a thermo :). Just got it...

Assuming you're using a decent size ladle, (anything somewhat larger than a teaspoon :lol:) at the melt temp range you've indicated, boolits with poor internal structure will be the result at ideal mold temp's. Get in the habit of starting with a 500F mold and 700F metal... naturally, there's room for adjustment in those numbers, depending on a whole list of stuff (e.g. mold material, mold block size, cavity size, cavity size with respect to block size, pouring system and alloy. If your mold temp and melt temp's are closer together, you may find that you don't even need to smoke your aluminum molds. Disclaimer: :lol: Some aluminum molds (e.g., large bore Lee molds) have so little metal remaining after boring out big cavities, that you may need to have a very slight amount of carbon in them no matter what your casting conditions.

MJ

375RUGER
06-08-2013, 08:38 PM
Wrinkled are rejects. Light frosting is OK, too heavy and your fill-out will suffer.

MtGun44
06-08-2013, 11:28 PM
Frosty is not a problem, wrinkled is a reject.

Bill

ku4hx
06-09-2013, 07:41 AM
Wrinkling is a physical defect; mild frosting to me is cosmetic. But, depending on several factors, both can shoot quite well. A wrinkle or two on a pistol boolit's nose (or those on the body sizing removes) are generally no big deal to me. Light frosting on tumble lubed boolits tends to hold the lube better.

44man
06-09-2013, 07:53 AM
The reason frosty is lighter is because too hot of a mold makes the cavities smaller. They are NOT holes in a solid block, metal expands away from a hole but a cavity is half a hole on the edge of a block so metal expands towards it.
The other answers are good.

Marlin Junky
06-09-2013, 01:08 PM
The reason frosty is lighter is because too hot of a mold makes the cavities smaller. They are NOT holes in a solid block, metal expands away from a hole but a cavity is half a hole on the edge of a block so metal expands towards it.

One can cast frosty boolits even if the mold is not at the proper operating temperature by pouring 850F metal. In this case, it's the temperature differential that produces light weight boolits with a weakened structure. When the temperature differential isn't as drastic, the castings solidify more uniformly with less trauma. :bigsmyl2:

MJ

44man
06-09-2013, 02:03 PM
I will not cast pure at 850*! 8-)

Frosty Boolit
06-10-2013, 10:06 PM
Frosty boolits never gave me any trouble.