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10mmShooter
06-24-2009, 10:33 PM
Hey Guys,

Check my cast weights, I'm around .40% deviation from total cast weight.

21 samples of each bullets, weighed averaged and SD calculated.


Lee 6 cav 401-175-swc avg weight 173.81 SD=.68 .39% deviation vs avg wgt
Lyman 4 cav 358477 avg weight 152.23 SD=.59 .38% deviation vs agv wgt
Lyman 4 cav 429421 avg weight 247.58 SD=.96 .39 deviation vs avg wgt.

I would like to hold my SD to less than .5 grain is this a resonable target, I only have a 10lb Lee Pot. I do use a thermometer, but I have noticed its hard to maintain a steady temp with little Lee pot.

Any tips I can use to tighten up my SD.

jhalcott
06-24-2009, 11:44 PM
I am one of the guys that just doesn't get TOO anal about cast bullets. I want them to hit the vitals of what ever critter I launch them at at a REASONABLE range for the bullet/load involved.IF it does that I am happy. I rarely shoot cast in competition any more. When I did, I was REAL anal! Weighed bullets to +/- half a grain. Same for cases ,powder AND primers. Took a thermometer to the practice sessions too. NOW life is easier.The gun goes BANG and the deer falls (or soon does) It comes down to how MUCH is winning worth to YOU. Grand pop said " IF you THINK it's an advantage,IT IS to you!"

Johnch
06-25-2009, 12:00 AM
Hey Guys,

Lee 6 cav 401-175-swc avg weight 173.81 SD=.68 .39% deviation vs avg wgt
Lyman 4 cav 358477 avg weight 152.23 SD=.59 .38% deviation vs agv wgt
Lyman 4 cav 429421 avg weight 247.58 SD=.96 .39 deviation vs avg wgt.

I would like to hold my SD to less than .5 grain is this a resonable target, I only have a 10lb Lee Pot. I do use a thermometer, but I have noticed its hard to maintain a steady temp with little Lee pot.

Any tips I can use to tighten up my SD.


I bet if you took 100 that weighted exactly the same
And 100 were + - 2 gr
Loaded them
IMO you could not tell the differance in groups

IMO your Sd is pretty darn good

John

10mmShooter
06-25-2009, 06:36 AM
Thanks everyone,

I agree with you guys I dont plan on weighing every run of bullets and again all I shoot are evil pieces of paper, I've just finished my first 500 rounds of cast bullets in my 3 calibers. Just want to make sure I'm in the ballpark :mrgreen:

pdawg_shooter
06-25-2009, 01:03 PM
I allow +or- 1%. That is 4gr on a 400gr bullet. Guess I cant shoot good enough to tell the difference.

Whitespider
06-26-2009, 05:40 AM
Question.... and not trying to hi-jack the thread, but...

I see a thread/post quite often about weight variances, and reject boolits are mentioned often also.

I’ve never cast a single boolit from a bottom pour pot, don’t even own a bottom pour.
I’ve also not cast any long skinny rifle boolits (yet).
But, using a ladle and casting .35, .40, .41, .44 and .45 caliber boolits weighing from 150 to 260-grains I rarely (almost never) see any that weigh more than +/- .5-grains from the mean. Actually, the smaller the boolit, the smaller my variances; the .35’s are usually within .2-grains of the mean. I also have very few rejects (sometimes as few as 1:50), other than the first half-dozen or so drops from the mold. Now, I will admit that I haven’t weighed every boolit, but I do usually weigh a random sample (about 10% of the batch) just to check.

Is this normal with a ladle? Or, have I just been lucky so far?