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larrye44
06-06-2009, 05:42 AM
I just cast my first boolits and inspected them for wrinkles and fill out. I weighed them and found a range of 200.0 to 206.0 grains. I guess due to the temperature changes while casting. My question is do I need to weigh the boolits and sort them by weight for match loads? I will be shooting NRA Bullseye Pistol. If I need to group by weight how's the best way to do so. Like 200 grains to 202 grains then 203-206 and so forth. Or is it even necessary? Thanks everyone for the help. Larry

versifier
06-06-2009, 02:30 PM
Welcome to the Guide, Larry.

Personally, I wouldn't think the difference would matter that much at 25yds or less, but I don't compete. For self defense I am happy to keep them all on the paper at 25 and 50yds and I don't care where on the paper they hit, as long as they hit it. You have a much greater accuracy requirement than I do, and that is more than the 2-3gr variation I like to see in a batch of bullets, so if I were in your shoes I'd be wanting to do some experimenting to find out what my pistol had to say about it.

I would try the following tests, keeping all variables the same except the bullets:
POI Shift
Select 20 that are within 1gr and shoot two 10shot groups as a control. Plot the center of each group.
Then select 20 more, 10 of each extreme and shoot one group with each extreme. Plot the centers of those groups. Compare the POI for all targets and see if there is a shift.

Group Size
Select 20 within 1gr and shoot two groups as a control. Measure the group sizes.
Select 20 more, 10 of each extreme, and shoot two 10shot groups using 5 of each in each group (5 lightest + 5 heaviest). Measure them and see if the groups open up compared to the control groups.

I am assuming that if there would be a noticable difference, it would show in both tests, so you can use them to double check. For most casual shooters, only a Ransom Rest would show enough difference, but as you compete in an event where accuracy counts (not merely hitting the target). That requires a very accurate pistol and a lot of practice to maintain your edge, so you ought to be able to test them without any artificial aids and get usable data. Please let us know what you find out.

FWIW, switching to a 20lb pot and 6cav mould should enable you to cast much more consistantly. I am assuming (maybe incorrectly) that you are using a 2cav mould and I'm wondering if you might have some voids in the bullets (you'll be seeing unexplained flyers), or if your alloy is consistent. Depending on the mould, sometimes you have to toss the first 20 or 30 back into the pot until all the temps are right and everything is running smoothly. Describe your setup if you want some help diagnosing what's causing it.

larrye44
06-06-2009, 04:57 PM
Thanks, versifier, for the great advice. I was not sure how much weight difference in a 200 grain LSWC would make. And, I would not have thought to conduct a test like you have laid out. I think it's great and it sure should tell me what my pistol wants.

Here is my method: I melted WW's in a 5 quart cast iron Dutch oven and stirred and fluxed several times. Made ingots of WW's (they are real clean). I ordered tin from Rotometals and when it came in I melted the ingots and added 2% tin and stirred and fluxed again and made ingots (small muffin pan) that would fit in my Lee Pro 20 bottom pour pot. When the melt reached about 750 degrees, I start casting. I check for wrinkles and fill out and throw back the rejects until the boolits look good. I try to add small amounts of lead so as not to bring down the temp. too much while casting. Once the mould (RCBS 45 201 SWC - 2 cavity) gets hot and I'm casting in a good rhythm, the sprue plate cuts the bottom of the boolit real smooth and there is no cavity. The boolits look good. The first bunch of approx. 500, I weighed and put into three groups. About a 1/3 was 203.0 - 203.9, the next 1/3 was 204.0 - 204.9 and the last 1/3 were 200.0 - 206.0. I guess it is going to come down to your test and then go from there. At least if your test shows that my pistol like the 204 grain boolit best, all I have to do is weight and make two groups 204.0 204.9 and all other. The all other will be my practice boolits. Thanks again, versifier. Larry

runfiverun
06-06-2009, 08:07 PM
larry adding one lb ingots to a 750* lee pot will lower the temp almost 100* for about 4-5 pours
try to break up or make your ingots smaller.
you also might want to turn up the heat in the pot to about 800 or so.
i also like to keep kitty litter on top of the pot, it helps to even out the heat and lower the oxides in the alloy.

versifier
06-06-2009, 08:22 PM
Let's talk alloy. There is usually enough tin in the WW's already, so I don't think you need to be going to the added expense of buying it in the future. (Another great source of very cheap tin is old pewter ware at yard sales. I'm sure you know someone who is addicted to them that would keep an eye open for you.) As WW's are getting harder to get and more expensive, too, consider an alloy of 1/4 or 1/2 WW/pure lead. You may have to add a bit of tin to that, but the softer bullets cast easier, obturate better, and seem to have an edge in accuracy - as long as they are large enough. Pure lead is always easier to come by (at least around here). Contractors/plumbers doing renovations often get old lead drain pipe, roofers/masons often have lots of scraps of lead flashing that would otherwise be thrown away.

That is a great mould. But, if you decide you want better consistancy, consider Lee 452-200-RF or 452-200-SWC. Both of them are available in 6cav. (My favorite is the 228-1R, and I have the matching 1cav HP to go with it, but that is heavier than you're using now.) My thought is that you can get the inexpensive 2cav versions to see if your pistol likes them better or equal to the RCBS you have now. If they are as good or better, then I would go with the 6cav. Once the mould is up to operating temp, you will turn out many hundreds of them (at least 4X the rate you can with a good 2cav mould) and they will be more consistent weight-wise from bullet to bullet. Lee 2cav's do have some serious quality issues sometimes, but the 6cavs are much better by far. I have a dozen of them, including some custom ones for rifle bullets and I'm very happy with them. I also own a lot of Lyman, RCBS, Ideal, Ohaus, etc. steel moulds of 1 & 2cav and I like them all, too, but for cranking out a lot of bullets, there's nothing like a 6cav.

runfiverun
06-06-2009, 10:58 PM
definately a softer alloy, i like to use about 20-25% soft lead with my ww alloy.
especially since the majority of my ww's are older and a good percentage of them are the old truck weights.
i try to get as close to a 1% tin 3% antimony alloy as i can .i waterdrop this alloy for my rifle boolits and can push this alloy pretty darn fast [over 2300fps in some cases.]
i have a fondness for older lyman 4 cavity molds, but i will probably choose some 6 cav lee's in the future [when they can be counted on and aren't so rushed] even lyman and rcbs have been showing some issues lately.
but they all do back up their product. and the 6 cav's are a big step up from their 2 cav's.

larrye44
06-07-2009, 04:25 AM
Thanks versifier and runfiverun. I'm going to use straight WW's as soon as I cast up these ingots. I won't be buying more tin now that I know WW's will work fine as they are. I will probably go for the 6 cavity mould later, but thought since I was just starting out, I'd be better off starting with a 2 cavity. I have noticed that once I get into a good casting rhythm that the boolits seem to be a lot more consistent in weight. I think I'll do better once I have a little experience under my belt. I have cast about 50 pounds of alloy so far and I can already tell a difference.

versifier
06-07-2009, 04:57 AM
I have noticed that once I get into a good casting rhythm that the boolits seem to be a lot more consistent in weight.

That's it in a nutshell. Each different mould has it's own personality. You know when you hit the correct rhythm: the sprue always feels the same when you cut and doesn't tear, the bullets fall cleanly from the mould and don't stick (if you go too fast, you try to drop them too hot - before they have started to shrink as they cool). Before long, you will be wanting to maximize time spent casting, then you can upgrade your mould. You're right thoroughly learn the ins and outs of the one you have, vary the alloys and the pot temp to see what happens. Add tin only when you aren't getting proper fillout and good sharp angles on the bullet bases.

Seriously, though, add more pure lead to your pot and your WW's will last a lot longer - there's more tin and antimony in them %wise than you need, so you can dilute them with pure lead. Every once in a while you will run into a pistol that will only feed hard bullets, but IME most do better with softer alloys.

I smelt WW's, linotype, and pure lead separately because I use different alloys for different purposes and can add the proper ratio of ingots to the pot for each alloy I want. The faster, the harder. Where you are just casting one type of bullet, you can either mix your alloy in the smelter and do that up in ingots, or you can do each component separately and mix different ingots as needed in the casting pot.

These are my usual alloys:
Handgun bullets use the least amount of WW's proportionately:1/2 or 1/4 WW/pure for low velocity and good obturation.
Rifle hunting bullets only WW's for good expansion with reasonably high velocity.
Rifle target bullets 1/1 lino/pure or just lino for no expansion, highest velocity.

runfiverun
06-07-2009, 03:02 PM
my alloy line up looks much like versifiers
i use the ww/pure mix in handguns and lever action rifles.
straight ww's for more magnum applications, ww's water dropped for some rifle applications.
a 4/6 mix instead of the 2/6 mix he gets with the lino- pure @ 50-50, this is used for small game/target shooting in the larger cals.
and some lino for my 22's so it will break up on impact with the little animals.