Cast bullet consistancy

Once you get the heat of the mold and lead heat working well together then you can produce a lot of equal weight bullets. The same pour speed and lead pool in the sprue plate will help too. Also filling the mold without getting air bubbles will help with weight and make them more stable.

I sort my Lee 55gn 224 bullets by the tenth of a grain. I have a storage box with dividers to keep them in. When I'm ready to load a batch for the bolt action rifles I pull out the weight with the most bullets. Next batch I go to the second most bullets and so on. I label all my loads when I put them into the MTM ammo boxes. Call me OCD, but it works for me.

If samples look ok, no visible flaws, i would expect less then 3 gr variations . Lightest to heaviest bullet.

45 acp 200 gr 8/10 gr. Small samples.
44 200 gr 9/10 gr.
9mm 120 gr 5/10 gr. If my math is correct.

I check 2 samples each, at start/ middle/ end of 10 lb Lee pot. Sprues go back in pot as i cast.

How the mold is filled makes a difference, maybe? Drop vs Pressure cast.

When i worked up a 45 acp load for competitions, i sorted by weight, each bullet from same lot. The loading had to stay in a 3" group at 50 yards, from a rest. 3.8 grs Bullseye & Lyman 200 gr BB was the most accurate.



Diameter is most important. Forget dropping bullets from mold to water to harden.

A tenth of a grain deviation in a cast bullet is not in the realm of normal. If they all were within a few grains your doing good.

Even manufacturers of precision match grade rifle bullets struggle to be within 1gr in a given batch of 100. Some do better than others.

I've found less weight deviation in a batch of the budget Hornady Match rifle bullets than in a batch of Berger's. But the Berger are more accurate.

A multi-cavity mold can have variation from cavity to cavity. Also, the alloy you use, temperature at which you cast and speed at which you pour all has an effect.
I don't sort and just use them as plinking ammo. They vary a few grains +/-, then I powder coat which also varies. Powder scale is +/- 0.1 gn and my seating die is +/1 0.005".
They all seem to go bang, cycle well and are fairly accurate in my pistols.

I have not cast for rifle yet.

I suppose to get more accurate ammo, I would need to sort the bullets and also get better control of the other tolerances in my equipment.

WeekendReloader said:

variation

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The 2 newly purchased Lee molds drop oval bullets. They are 2 cavity molds.

My iron Lyman & Saeco produce rounder bullets. Big difference in cost.

Oval is not an issue, if as cast bullets have enough diameter to size to the required diameter.

For what it’s worth, I believe that weight consistency (within reasonable limits) is much more important with the smaller calibers than with larger.

I cast from Wheel Weights, taking no exotic measures with my casting technique, do not weigh my bullets, only discard those that are obviously malformed....yet manage 1” to 1 1/2” groups @ 100 yards using a 4 x scope with my 45-70 Marlin GG using 430 grain bullets. Same process using 400 grain bullets in my S&W 8 3/8” XVR with a 3 mil, reflex sight gives 2 5/8” to 3 1/2” 4 shot groups @ 100 yards. The reason for 4 shot groups is....I have one bad charge hole which consistently throws one out of group. I’m pretty pleased with the performance of the larger heavier bullets.

Using smaller caliber cartridges, .270 up through .375, the bullet weights and appearance seem to be more critical! If I want good accuracy with the smaller stuff.....a more thorough sorting procedure is required! At least, these are my findings! ymmv memtb

I cast and load lots of 9mm, mainly the Lee 124TCTL and now also the 124 2R. I haven’t weighed one in the last 300# and I don’t shoot them past 25 yards so maybe it doesn’t really matter up close. If I was loading rifle with any plans for accuracy I’d probably weight sort at least initially to see if it was worth it. I get nice tight groups with my cast, just like the rare occasion I shoot jacketed so I don’t bother weighing them.

Made me weigh them just to see. The 124tc is 132.6-133 and the 2R is 126.4 +-.45

I just got a Lee 253-252 SWC mold for 45 Colt. Out of the 100 I cast 76 were 258 to 258.9, 20 were 259 to 260.4 and the last 4 were 256 to 257. Needless to say I’m really happy with that. Don’t know if it was a fluke or not but next casting session will tell.

Casting can be tedious especially if you have the single casting mould but I have found through experience that the single and the 2 bullet mould to cast more precise bullets than when you try the 3 or four type for expediency. For my 45/70 I always use the single mould and for my 45 acp and .357 the double. As @FROGO207 mention everything plays a vital role at times I feel that even canting my mouth to one side and biting my tongue helps too. Experience will take time and you will get better as you learn more through sticking to casting.