typical boolit weight variation

[varmint243]

I cast 300 boolits with a new mould and am getting what I feel is a lot of variation in weight.
It's a Lyman 38 148 full wadcutter.
I am using range salvage lead, I shoot target velocities so hardness doesn't matter much.
A friend did a harness test and it is more or less what WW is.
Here are the numbers I ran on a small random sample.
Is this what you would expect ?
A friend suspects my lead is dirty, I use a Lyman bottom pour, so I assume all the crud goes to the top.
Thoughts ?

Pact Scale +/- .1
no lube

142.6
143.3
143.3
143.5
143.7
143.7
143.9
144.0
144.1
144.1
144.6
144.7
144.7
145.0
145.7
145.9

average 144.2
max 145.9
min 142.6
median 144.1
stdev.s 0.9
max spread 3.3

average 144.2
div/100 100.0
1 percent = 1.4
spread 3.3
percent of bullet weight max spread 2.3%

average 144.2
div/100 100.0
1 percent = 1.4
stdev.s 0.9
percent of bullet weight stdev.s 0.6%

[detox]

Yes that is alot of variation. I be sure to stir and flux melt about every 50 boolits when using bottom pour. My boolits usually vary in tenths

For instance:
2@159.3
4@159.4
10@159.5
20@159.6
10@159.7
4@159.8

Make sure mould is closed fully and sprue plate bolt does not loosen when casting. I crank down on the lock screw to prevent bolt from loosening.

[44MAG#1]

I would rather for mine to be closer but if your a good enough shot to tell the difference between those and weigh matched bullets you are a super shot. Especially at the distances you will be shooting those type bullet.

[10mmShooter]

For my 25yd pistol shooting at less than 1000 fps with my .357, 10mm and .44 loads, weighing pistol bullets is a waste of time...just my .02 cents even a 5 grain weight difference at 1000 fps over 25 yds point of impact is just not going to move enough to matter out of a pistol. and then throw in slight variations in powder charge too, variations in different brass case capicities and you get the point. Also as you have indentified 1-2% weight variation is just not going to matter for general target and plinking work...spend more time casting and reloading and shooting and less time weighing :)

I do on the other hand weigh each and every one of my cast .308 bullets.

[varmint243]

I just got back from a range trip and they shoot very well.
I shoot 40yards offhand double action - no 50yd handgun line at my club/range :-(
I shot two 10 shot groups 5" - 6" without workin' too hard at it.
I think less than a 1% difference in boolit weight doesn't make much difference.
However I do believe a nicely flat square base does matter and that is what I check each one for.
My general sense is that these are very accurate.

[Brenden]

How many bullet mold are you using? You may be getting your variation from a particular hole in your mold. Try to eliminate the variables by keeping bullets cast from each chamber of the mold separate.