as cast weight spread?

[x101airborne]

So, lets say same redneck from previous post :redneck: cast around 80 300 gr gas checks 44 cal today from bhn 19-20 metal. mix of linotype, range lead, isotope cannisters, wheel weights. same redneck weighed said batch of boolits and found around a 9 grain total spread. not .9, 9. I (whoops), he decided to take the largest group of 4 grain total variation 293 - 296 grains. problem is, this is only around 60% of the total group. Besides obvious variations (way too heavy, way too light) what is a normal weight spread to have? I have tried to control temp with a thermometer +- 10 degrees, made sure I poured the same, and have only two cavities, so there should not be much variation. The last batch I loaded shot great, so am i worried over nothing? Could this be the reason for the occasional flyer? Also WTH causes some boolits to have little burrs or rough places on the sides where the mold was smooth? none of it REALLY bothers me if they shoot, but i am striving for those pretty boolits yall post pics of that just seem to elude me.:sad:

[Rocky Raab]

In my continuing role as Everyman Reloader, Colonel of the KISS principle, your first mistake was weighing the darn things. Or maybe the second. Your axle seems to be very tightly wrapped.

Cast 'em. Load 'em. Shoot 'em. Grin. Repeat.

[x101airborne]

LOL, rocky...... i figured that was my problem.

[Rocky Raab]

Crisp salute, my brother. Carry on.

[SharpsShooter]

If your temp is good and alloy clean, 9gr variation is likely the pouring method or one cavity is a smidge (that's a technical term ya know) larger. I'd lean toward the pressure of your pour as a strong possibility.

Bottom pour or ladle???

SS

[btroj]

I'm with Rocky. You can weigh boolits? I have a powder scale, where do I get a boolit scale?

Maybe if I was a group shooter I would worry, but for my purposes I can't see weighing boolits. I sort out the obvious flaws and shoot the rest. I will admit to sorting a bit more carefully before loading hunting rounds but since I shoot deer at less than 25 yards most of the time I don't know why I even do that.

Brad

[Blammer]

since you've wt and sorted them, I would do this.

put one batch next to the other then visually inspect the boolits very carefully. You'll start to see the heavier boolits most likely, have better fill out on the corners ALL the way around and from top to bottom, the edges will probably be sharper, and no 'hollow' divit from the sprue.

I'd say you're pouring technique is what is causing the variance. I'd load them by wt groups and shoot them that way.

Yes an occasional flier may be because of a "heavy" or a "light" wt one getting in with the "regular" ones.

[GabbyM]

You didn’t say what method you use to cast.
With a 300 grain 44 you may want to try ladle pouring. With pressure using a Lyman or RCBS ladle with spout. With some big moulds I get good results with a Rowel ladle.

With those big bullets you can get quite a bit of shrinkage where the cavities are close together in the middle. Plus it’s hard to get enough volume with a bottom pour.
Pressure pouring with a ladle seams to cure the shrinkage. At least with several big bullets I use. I also use ladle pour with pressure on 22 caliber rifle bullets.

[HeavyMetal]

For everyday general shooting if they go where you point them don't worry about it.

If your concerend about a flyer missing game or your shooting for score then yes weigh them then sort into batch's by weight and keep them about 2 grain apart, max spread.

What I look for when I weigh boolits, and yes use one of the good digital "powder" measure for this, I am not looking for nit picky uniformity as much as I am looking for the way out of bounds boolit weight, that would be 6 to 10 grains to light or to heavy, and remove them from the loading process and remelt.

Weigh some factory jacketed some time and see how uniform they are, it can be a bit of a surprise!

[MtGun44]

Run this test.

Pick 5 heavy and 5 light and load them. Shoot a 10 shot group at your normal distance.

Mr. Target will tell you if you have a problem. Mr Scale has no idea.

Bill

[Trifocals]

If I were to guess, I would say you were probably using a bottom pour pot. Be sure to always make sure there is a generous puddle of alloy above the sprue hole. A little weight variation in handgun bullets isn't earthshaking out to perhaps 50 yds, unless you are shooting in competition such as bullseye. Reaching out past 50 yds as in silhouette competition calls for boolits as uniform as possible and I normally will segregate by weight. Where uniformity in weight is a factor with either rifle or handgun bullets I use a dipper. Once a person learns to cast boolits properly with a dipper you can expect much greater uniformity.

[runfiverun]

wow 3%. WEIGHT VARIATION.
i sort by eyeball.
even my 223's. unless i'm going high velocity or impressing the targets.
if your gonna weight sort you need to cast one boolit all day under the same humidity conditions.
if your gonna obsess about it you need a one cavity, a clock that ticks audibly, a mold lock, and a repeatable large volumn of alloy, and a pot that will hold it's temp reliably from top to bottom.
i probably left a few things out.

[Dale53]

There is absolutely no reason to settle for a 9.0 gr variation. I use a bottom pour pot exclusively.

My LARGE bullets (BPCR Silhouette bullets) I weighed them (shooting 500-600 yards). I kept them within plus or minus .6 (six tenths of a grain). My Schuetzen bullets (about 223 grs) were plus or minus .2 of a grain (shot from a genuine half minute bench rifle).

My run of the mill pistol bullets almost NEVER get weighed but I am happy with them if they go plus or minus .6 of a grain.

I have been casting a very long time and several hundred thousand bullets. If you work at it, you too can get MUCH better.

YMMV
Dale53

[fredj338]

As noted, the larger the bullet the greater the weight variation. I only weigh my LHP used for hunting or bullets for longer range shooting, where flyers will mess w/ my accuracy. A 1% variation is acceptable, I have seen little accuracy decline sticking w/ that. As much as you like to think you are controling temp, as you cast, the temp goes up, shrinkage is greater, weights will vary. I use a bottome pour, pressure acsting most bullet types. If I weigh a batch, they will vary less than 1% for completely filled out bullets. Internal voids & incomplete mold fill out are the biggest culprits.

[rintinglen]

I'd put my money on incomplete filling. I use a bottom pour pot exclusively , and it is rare for a good mold to throw bullets more than 1 grain apart.
However, there is one other possibility.
I once threw a couple of ingots into the pot that turned out to be pure tin--those bullets were much lighter than the ones that had come out just a few minutes before. 20 percent tin makes for some darned light bullets--my normal 190 grainers were dropping at a feathery 173-174. Once I figured it out, I drained half the pot and filled the rest with wheel weights, drained half again and refilled with wheel weights. then spent the rest of the after noon smelting the various ingots until I had about 40 pounds of sweet casting metal.
You don't have to be a redneck for things to go south.

[qajaq59]

Pick 5 heavy and 5 light and load them. Shoot a 10 shot group at your normal distance.And don't be too surprised when they all shoot pretty much alike in you have a hunting rifle! I tried that a long time ago and there was more problems with wind gusts on the range then with the slight variations in weight.