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dddddmorgan
05-05-2021, 10:29 PM
So I guess I'm kind of posting a poll, I'm wondering what you have for your personal level of acceptance in weight variation on your boolits?

I have a great Lee mold that throws 159 grain "cowboy" boolits 6 at a time, my standard is 2 grains, 158-160 is good for me.

I have an RCBS .45 KT mold that is absolute perfection, it will throw boolits within half a grain all day.

My Lee mold with the cowboy boolits is not for fussy shooting just something to use informally.

So what's your standard?

Thanks

JM7.7x58
05-05-2021, 11:01 PM
I have never weight sorted my cast bullets. I get 2 1/2” ten shot groups at 100 yards with my most accurate cast loads. This is in a 103 year old model of 1917 30-06. This same old rifle does about 2 1/8” with factory jacketed.

I do however inspect all my rifle bullets and discard all visual flaws. I do the same inspection with my 38 and 357 bullets that I shoot at longer range with my six inch revolver. Years ago I was given a Hi-Point in 45acp, this is plinking ammo that my boy and I bang through at close range, I don’t mind a few wrinkles as long as it has a good filled out base on these bullets.

Maybe I’m doing it wrong.

JM

robg
05-06-2021, 05:51 AM
i do weigh a random number of boolits ive cast as long as they are within 1% variation i treat them all as the heaviest ,im more critical of the bases they have to be perfect.

charlie b
05-06-2021, 07:15 AM
It depends on what your accuracy tolerance is.

For my rifle bullets I am a bit picky.

I can have quite a difference, 2 or 3 grains with 200gn bullets. When casting I get rid of obvious defects as I cast (they go back in the pot with the sprues).

When I am done casting I start inspecting and weighing. Defects and anything more than 2gn light are put back. I then process the bullets. Size, gas check, powder coat and size again.

Then I sort. 0.1gn batches. I end up with a few piles of bullets that do not vary in weight and I keep those separate for my most accurate loads. I will end up with a bunch that are 'strung out' and I sort them into 0.5gn batches. These are my 'plinker' rounds.

Why the 0.1gn batches? At 200yd I found that I get a significant accuracy gain. With 0.5gn batches I will see 1-1.5MOA groups. With the 0.1gn batches I am seeing below MOA on a regular basis (not all the time, just a lot of the time). At longer range it is even more apparent.

For pistol bullets?

I don't weigh them at all. I just check to see if the drive bands are filled out well and the base is square. I have no idea what the weight spread is on any of them.

Cosmic_Charlie
05-06-2021, 07:23 AM
When I get a new mold I weigh a few boolits to see how close it is to spec with my alloy. After that, not so much.

HATCH
05-06-2021, 07:42 AM
These are pistol rounds.
Unless you are weighing each throw of powder what's the point in weighing each boolit??

I physically inspect each boolit.
Look for deformity and check the base where the sprue is cut.
Sprue cut is a huge determining factor. Any pin holes mean that the boolit definitely will not weigh close to the designed weight.
I don't weigh them. 95% of my casting is pistol boolits.
I don't shoot 100 yards with them so being a few grains difference won't really matter as unless you can place them all in the same hole when you shoot them its a waste.

high standard 40
05-06-2021, 07:49 AM
It depends on each person's accuracy demands, based on the type of shooting they do. If the majority of your shooting is with a handgun at 7 yards, weighing is a waste of time. If you strive to win a top level competition event, it's not a waste of time to weight sort.

There's another reason to weight sort. It is a very good aid to help you refine your casting technique. Weighing will show you if you are casting consistently. If your weight variation is wide, you may need to adjust your technique to improve consistency. Once you find the methods to get good results, weighing may be less important.

I weight sort all my competition bullets. I don't for semi auto handguns.

dverna
05-06-2021, 09:11 AM
Weighing pistol bullets is a waste of time unless you are NRA Master or high Expert and shooting the 50 yard slow fire targets. A visually inspected bullet will be as good as you need for 25 yard Time and Rapid fire.

Cowboy shooting used to be 8-12" plates at about 7-10 yards...any crap will hit the plates.

Save your time and stop weighing bullets. I hardly ever rejected pistol bullets. Any that looked a bit "off" would be used for practice ammunition. I was shooting 400+ rounds a week and hated casting.

A good mold, good alloy, and consistent casting cadence produces very few rejects. Spend time and money in those areas instead of QC'ing. With a good process, QC is minimal.

dddddmorgan
05-06-2021, 09:50 AM
Thanks for all the input.

Yeah, I'm probably too fussy worrying about pistol bollits as I'm not shooting any match grade accuracy requirements. Visual inspection should be sufficient.

Interesting point about the sprue plate cut, I noticed that this was a big factor in weight deviation.

Okay, casting away, now on to rifle boolits...

Conditor22
05-06-2021, 09:59 AM
Weigh pistol boolits -- never have. I can't see well enough to shoot pistols far enough to warrant weighing them (and I refuse to put a scope on a handgun)

I do pay attention to complete fill out on the bases (if your not getting complete fill out on boolit bases heat up the sprue plate with a propane torch)

kevin c
05-06-2021, 11:48 AM
My application is not very demanding accuracy wise, but the rules of the sport (action pistol) do require a minimum power factor based on momentum (speed times bullet weight) and are very punishing if the ammunition used falls below that. So highly consistent ammunition is valued, having predictable PF, and that can be achieved by consistent loading technique using consistent components, including bullets with little weight variation.

Once up to temp and with good casting technique, my Accurate and MP molds will routinely throw boolits from all cavities that are within a couple tenths of a grain of each other. Since I use analyzed source metals and am careful in pre mixing my alloys I also get batch to batch consistency. The end result is that by culling for visual defects as I cast I end up with such consistent weights that I only weigh samples out of a batch as confirmation and no more.

Anyway, I have to confess that it's personally satisfying to cast really good boolits, so I'd do so anyway even without the justification of the rules.

HATCH
05-06-2021, 12:05 PM
Also I machine cast with a automated Master Caster.
After five mins of running, the caster puts out the same Boolits every time.

If you use the same alloy and run a PID on your furnace then the only variable is you casting.


Sent from my iPhone using Tapatalk

Jim22
05-06-2021, 12:22 PM
So what's your standard?
Thanks

I have tried weighing rifle boolits after casting. What I found with 200 gr .358 boolits is that 80-90% wind up within two grains of each other. The rest are either lighter or heavier. I understand how some turn out lighter but have not figured out how a few turn out heavier. With a 200 gr boolit 2 grs is within one percent so I accept them.

Jim

dtknowles
05-06-2021, 01:56 PM
For any bullets I am weighing I allow only a half a percent variation, ie, plus or minus 0.3 grains on a 140 gr. bullet. I only weigh bullets that I am going to shoot from very accurate firearms.

dddddmorgan
05-06-2021, 02:06 PM
I have tried weighing rifle boolits after casting. What I found with 200 gr .358 boolits is that 80-90% wind up within two grains of each other. The rest are either lighter or heavier. I understand how some turn out lighter but have not figured out how a few turn out heavier. With a 200 gr boolit 2 grs is within one percent so I accept them.

Jim

A question I have as well. Should you consider everything as lighter from the heaviest bollit? I think as everything is fluxed and mixed well there wouldn't be a possibility of one bollit or another having that much more lead?

bruce381
05-06-2021, 03:28 PM
I inspect and any not perfect go back into pot, that said I stay within about 1/2 %.

Goofy
05-06-2021, 05:16 PM
Bullets over 200 grains: .3 grains for the lot, separated in .1 gr sub lots
under 200 gr; .1 gr, separated in equal weight sub lots

gwpercle
05-06-2021, 06:24 PM
Handgun boolits :
I don't weigh them ... too time consuming .
Close visual inspection ... perfect base , well filled out , sharp edges .
No visual defects like a void or wrinkle or holes .

Light frosting is good. If I'm going to take the time to cast boolits I want as perfect a boolit as I can cast .
I flux often , don't skimp on tin and pressure cast with 2 - 3 - 4 cavity moulds and a spouted dipper .
This gives me the most visually perfect number of boolits (keepers) in a session .
A bottom pour pot gives me a large number of imperfect boolits that get thrown back into the pot and thus lower production of keepers .

Weighing handgun boolits is more wasted time ... for rifle boolits ... it may need to be done , that's another story .
Gary

dddddmorgan
05-06-2021, 06:32 PM
"Pressure cast"... oh here we go... please explain.

Mk42gunner
05-06-2021, 07:19 PM
When I get a new mold I weigh a few boolits to see how close it is to spec with my alloy. After that, not so much.
This is pretty much the way I do it too.
For what its worth, I have three different Lyman 452460 molds (a nominal 200 grain SWC) two DC and one four cavity. They all run 206-7 grains with my particular batch of WW.

Robert

wv109323
05-07-2021, 03:38 PM
I cast about 400 200 g. SWC .45 cal boolits. I picked out the obvious rejects(wrinkled, rounded bases and bullets before the mold was up to temp.) I then picked out the worst ten I could find. I loaded them up and shot them through an accurized wad gun in a Ransom Rest.
At the same time I loaded some commercial cast bullets of the same configuration and shot them back to back in the rest.
Group size was the same at 3 X 1 1/2". One group was more horizontal and the other more vertical. I visually inspect and use the rest.
More points will be lost by the shooter than by the bullet in competition.

dddddmorgan
05-07-2021, 07:48 PM
More points will be lost by the shooter than by the bullet in competition.

Well put!

dtknowles
05-07-2021, 10:01 PM
More points will be lost by the shooter than by the bullet in competition.

It matters more in some competitions than others but with two equal shooters shooting equal guns it will be the ammo and luck that determines the winner.

Tim

high standard 40
05-08-2021, 07:46 AM
It matters more in some competitions than others but with two equal shooters shooting equal guns it will be the ammo and luck that determines the winner.

Tim

Well put, Tim. Traditional handgun ammo shot at 50 yards, and sometimes much closer, is affected very little by defects in the bullet. I do not believe that when the distance is 200 yards and the target is small that the same holds true.

David2011
05-08-2021, 09:36 AM
"Pressure cast"... oh here we go... please explain.

Pressure casting is a technique where the spout of the dipper or furnace is held in contact with the mold cavity opening. It gives the full head pressure of the molten lead column to the cavity. With a dipper that’s a little extra pressure; with a furnace it’s much more pressure but it’s also another variable with a furnace as the lead level changes.