How much weight variation is too much and how do I control it.

[Crytes]

I've just started casting and while using the same alloy with the 312-155 mold I'm getting weights ranging from 60.5gr to 65.1gr the first melt most were in the 61 +/- .5 gr and the second melt the only change is that I was water dropping them and most were 62 +/- .5. I've been sending any out of the stated ranges back to the pot along with any with visible blemishes. Am I having a problem or being to critical?

[runfiverun]

I don't think you are being too critical.
keeping your mold temp, alloy temp, casting cadence, and closure pressure on the mold consistent will help.

[pdawg_shooter]

I have always allowed +/- 1%. Works for me anyway.

[DeanWinchester]

I used to be SUPER anal about it. I would separate everything into lots that were +/- .1g AND that was after gas check and lube. One day I was so disgusted by the labor involved, I ran an experiment. I loaded 20 rounds, all loaded with boolits that were +/- .1g and the powder charge was hand weighed to dead nutz each time.

I loaded 20 more. They varied by more than 3.0g I set my powder measure, checked it one time, and threw the charges without checking it again.

Range time came, at 100 yards....they shot the SAME! THis is for (4) 5 round groups and the mean grouping was less than 1/16 difference with the edge going to the hand weighed groups.

I pondered this for a moment. I dont bench rest, I dont compete and my happiest times shooting are hitting clay targets off the berm at 100 yards or less. My conclusion: its an absolute waste of time for the majority of us who are perfectly satisfied with shooting 5 rounds of ANYTHING inside an inch at a hundred. Does that mean that there is no benefit from the practice? Certainly NOT! There is great benefit to it......if you shoot longer ranges and/or compete for precision groups. For people like me, who cant shoot fer sheet any who, theres no need in worrying about it.
I will say this much, I will continue to finely separate by weight when developing a load. That's different as we need to remove as many variables as possible when searching for that sweet spot.

Have fun, lighten up, TRY them and if they dont group, try something different.

[BruceB]

I agree with Dean.

For quite a while now, I simply don't weigh bullets.

Why? Because after weighing a number of big batches (over 800 bullets each) I found that a quick VISUAL inspection under an illuminated magnifier-lamp was catching MORE imperfections than weighing did. I discard bullets with observed imperfections while casting, too, as well as on final inspection.

Like Dean, I don't shoot benchrest matches or other competitions, and for my purposes the bullets are just fine. Accuracy is ample for my shooting.

[Crytes]

thanks guys nice to know that practical accuracy at realistic blackout ranges that the difference is minimal. I'm new to both casting and reloading and only knew that consistency is key to accuracy but not the amount of effect each variable has. This first batch is mostly for function test anyway and finding my pressure range. Probally be some time b4 I'm ready to shoot for groups. Been reading about bore slugging as well so there is more to do there when I start hunting for acuracy

[detox]

I have a Lyman two cavity mould (358665) that drops different weight boolits from each cavity. If i seperate boolits from each cavity (not hard to do) each will weigh within less than 1/2 gram. If i mix the two cavities boolits will range within 2 grams. So yes i seperate boolits by each cavity....especially using this certain Lyman mould.

[pdawg_shooter]

With my 1% rule a 400gr bullet can very from 396 to 404. I can't shoot good enough to tell the difference.

[HATCH]

If you are shooting a mile then you would want everything to be perfect every time.
I personally don't weight my boolits except to count them.

[Pb2au]

Interesting;
I just went through the same thing the other day. I almost couldn't help myself, so an hour later my lab bench was covered in rows of bullets, each with a tape label at the top noting the weight.
What I arrived to was a deviation range over 300 sampled bullets of 3 grains, +-. I had four that were 6 grains light. I inspected closely those characters and discovered a void just under the sprue mark. I concluded those must be from the beginning of the run and the mold was a wee bit cold.
My take away was that again for melon killing, it really didn't make any difference. My history with that boolit (45 colt) and load in my 92 was still very respectable 10 shot groups at 100 yards. Now, that being said, for sure there are those on this board that operate their rifles at a level that for sure +-3 grains would make a considerable impact on their standards of performance.

[gwpercle]

Stop weighing them.
Give them a good visual inspection, perfect base, well filled out, no wrinkles...shoot em.
When I got a new scale I started weighing boolits and discovered they didn't all weigh exactly the same...got all obsessive-compulsive about it . Then groups with all matching weights showed no difference in size than the groups with variances...so I stoped weighing them and now I'm not OC-DC any more. Ignorance can be bliss.
Gary

[.30/30 Guy]

I too agree with Dean.

I weighed out some boolits and powder charges and compared them against unsorted and powder charges from a powder measure. Actually the unsorted ones shot better! Results may change with a much larger sample.

[BruceB]

Perhaps a few examples will demonstrate why weight variation isn't a factor in my casting.

NEI 2-cavity 421-390 (.404 Jeffery)... sample was 200 bullets, HEAVIEST was 400.2 grains, LIGHTEST was 399.2

RCBS 416-350 (.416 Rigby) sample of EIGHT HUNDRED bullets, heaviest 365.6, lightest 364.2, rejected SIX for visual flaws....did I ever tell y'all how much I like RCBS moulds?

RCBS 35-200 2-cavity (.35 Remington) sample of 120 bullets... heaviest was 202.4, lightest 201.5

With miniscule spreads as above, I think my fast-and-hot casting technique is well-vindicated and the consistency of the bullets speak well for the routine. Fill-out is obviously complete and consistent.

All the above bullets were cast with straight clip-on wheelweight alloy.

One note about my highly-regarded RCBS moulds.... I have their 2-cavity 270-130 mould, and this one drops bullets which are precisely ONE GRAIN different from each other. I filed an almost-microscopic notch on the meplat of the "lighter" cavity, which makes separation of the production very easy. In loading separate batches from each cavity, and a third batch using mixed bullets from both cavities, I found no difference in the resulting groups at 100 yards.

[paul h]

I've never weight sorted cast bullets, only visual inspection and sometimes I cull alot of bullets, sometimes very view, just depends on if I'm on with the mold or not.

With visual sorting my cast bullets will group 5 into 1" at 50 yds or 5 into 2" at 100 yds if the rifle or handgun and load is up to it. I even managed a 5 shot 1" group at 100 yds once.

If I was shooting competitively, then I'd definately weight sort bullets. But for my use, visual sorting provides all the performance I'm after. This from a couple dozen molds from every maker in 30, 35, 44, 45, 475 and 50 caliber and over 1000#'s of ww's over a dozen years.

[kdiver58]

100% it depends on how far I'm shooting. If I am shooting a silhouette match I weigh the boolits to one grain. But for hunting and anything under 50 yards I do a void QC check and shoot them.
Unlike what others have said .. MY testing shows that it did make a difference at 75 and 100 yards. Them turkeys and rams are little at those ranges.

[rintinglen]

You ask how to control weight variance? Cast the same way each time and try to keep the mold at an even temperature. Cadence is your ally when it comes to casting. Whether fast or slow, provided you go quick enough to keep the mold hot enough for a good fill, you will get consistent weights through correctly repeating the same tasks in as near an identical manner as you can manage.

The biggest enemy that the new caster has is the tendency to stop, ponder and paw his new boolits as he is casting them. You'll be far better served to cast THEN inspect after the casting is done.