Cast Boolits Expand Over Time?

[Atakawow]

What am I missing here? I got a batch of 125gr LRN casted about 2 weeks ago. Straight WW, water dropped, TL'd, sized to .357, TL'd again. Last week, these were measured at .357. Today I tried loading them, to my surprise, they were all in the .359 range.

Did the bullets expand or what?

[Huntducks]

It was the water that made them grow:kidding:

[cbrick]

What are you using to measure them?

Rick

[RobS]

I haven't seen much in regards to growth of water quenched WW alloy after sizing unless the boolits were smaller than the sizing die and didn't get sized or sized very little; merely lubed rather then they can become larger in diameter.

[Atakawow]

What are you using to measure them?

Rick

Sadly, a caliper. However, I tried best not to squeeze it.

[Atakawow]

I haven't seen much in regards to growth of water quenched WW alloy after sizing unless the boolits were smaller than the sizing die and didn't get sized or sized very little, merely lubed.

Bullets were dropped at .357-.359. Basically I TL'd, sized to .357, TL'd again, then measured at .357, all within 24 hour of the bullet being casted.

Should I wait a few days before sizing?

[RobS]

Waiting a few days will help keep them the same diameter since much of the growth appears to be in a weeks time with water quenced WW alloy, but they may be harder to size.........pick your best option. If your boolits are coming from the mold unround .357-.359 then sizing down isn't going to be a big deal even with the boolits being harder. You won't know until you try it.

[geargnasher]

RobS and I are doing our own little experiments right now regarding age-growth and how it is affected by alloy, sizing timeline, and hardness. Right now it's difficult to say since many of us have different experiences due to different variables. I'd say that if the boolits are still growing after you size them, then perhaps you should wait a full week before sizing them, or size smaller while they're still fairly soft. Most water-quenched alloy will be stable in a few days in my experience, a few members report that sizing their boolits while still "green" (actually knocking a thousanth or more off the bands, not just grazing them) seems to halt the age-growth. I haven't pinned down the exact factors involved, but I HAVE had the same nasty little surpise that you did on more than one occasion where the boolits were eating too many cookies while I was asleep and then got too fat to chamber.

Gear

[303Guy]

... then got too fat to chamber.So that's what's been going on! Damn! I've just been trying to figure out why some of my castings don't fit (thinking I've got more molds than I remember). Seemingly identical castings fit and don't fit :!:

[44man]

I don't really size my .476" boolits, just lube and if I do it soon after casting, they grow to .478". I have had to size again for some guns.

[357shooter]

From the tests I've done, they grow/expand to maximum size in 2 weeks. Then shrink again. The lubed bullets that I tested didn't expand quite so much as yours did.

The test is with soft alloy so the amount of expansion is different for WD-WW, but the affect is the same. (I suspect.) I haven't done longer term testing than 4 weeks, the results from those tests will be very interesting.

http://357shooter.blogspot.com/2011/02/final-report-on-changing-bullet.html

I'll try posting the chart here too. The blue is an unlubed bullet, the green is a lubed bullet:

http://i878.photobucket.com/albums/ab341/prgallo/Week4ofaging.png

[XWrench3]

i usually dont have to worry about this. i usually cast months ahead of time, and i do not size anything until i am close to using them. anytime i drop below 2 jugs of any boolit, the pot comes out, and i cast up roughly 15-18 pounds of them. sometimes, i dont have to cast for a size for almost a year.

[bhn22]

Antimonial alloys often "spring back" a bit after being compressed (sized).

[1Shirt]

I have had cast from water dropped WW with a cup of mag shot, sized .312, grow to .3135 after a few days. I usually size and lube on the same day I cast. Checked with mike on a number of blts.
1Shirt!:coffeecom