sizing problem

[win1906]

i just started casting a couple of weeks ago.most of the bullets came out looking great.sharp edges and no wrinkles.then i went to size them in a lyman lube-sizer.the crimp groove and lube groove get shaved off.am i missing something.i have read the lyman cast bullet handbook cover to cover twice.i am just not getting it.why try and size your bullets when you just shave off the lube grooves.any help would be appreciated.

[captaint]

We need to know what size your boolits are supposed to be - and what size they actually are after casting. Sounds like you are sizing boolits that are too big to start with. I normally don't like to size off more than maybe 3 thou. .001 is better - best... Would also help if we knew the dimensions of your sizer die. Mike PS. Welcome to the best site on the net. More knowledge here than one can imagine. And lots of very friendly folks.

[Pb2au]

^captaint is on it. For sure it sounds like you are sizing down aggressively.
Let's find out what size you are starting with and what your target is.

[JonB_in_Glencoe]

win
a picture might help your explanation. Is there actual shavings ?
IF SO...
I've heard of older Lyman dies that have a ridge inside that actually shaves the Lead off instead of sizing the boolits by swaging. I have some old dies, but none of them do this. Take a look inside the die, let us know what you see...if there is a ridge, it suppose it could be chamfered?

[win1906]

i am going by the lyman cast bullet handbook.the last one i tried was for 303 british.lee 312-185 mold ran through a 313 sizer.most of the grooves shaved off.i did not mic. them but most be casting alot larger then the mold says.other lyman molds are doing the same.my lead is any ones guess of what it is so maybe that is the problem.

[singleshotman]

if the mold was made with a new cutter, it could be very oversize. I once got a brand new 32-40 mold that was supposed to be .321 but I came out cast at .328, needless to say it was useless to me as they were ruined when sized. You should never size more than .003, and less than that is better.

[JonB_in_Glencoe]

It's tough to troubleshoot a problem like this without a mic

[RogerDat]

If you cast with the lead a little hotter won't it contract more in the mold as it cools? Conversely if you cast with melt at the cooler end won't it contract less? Both would change the as cast size. I have no idea of the expansion coefficient but do know amount of tin vs. lead can change mold output size because high tin does not expand as much or maybe it's more than plain lead. Brain fuzzy on details.

What win1906 said is true cutter being new could make a larger mold. Seen it in shops before. Bet some folks with worn 303 British bores would love that oversized mold.

In response to a PM I checked, it is antimony that reduces the coefficient of thermal expansion more than the tin does per percentage(.8 vs. .06) 2/4/94 alloy would have about .92 lower coefficient of thermal expansion than plain lead so if cast at same temperature would contract less at cooling than plain lead thus giving a larger bullet.