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joeb33050
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Bullet weight info needed
Dec 20th, 2004 at 7:32am
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I'm looking for the information on the results of weighing cast bullets. I particularly need the results for heavier cast bullets, over 299 grains. Light is good too. Maybe 22 and 25 caliber bullets. The ideal information would have mold maker/number, and the weights, sort of like this:
Lyman 457125
524.0      1
524.1      0
524.2      6
524.3      8
524.4      19
524.5      32
524.6      76
524.7      41
524.8      28
524.9      11
525.0      12
525.1      7
525.2      2
525.3      0
525.4      1
525.5      2
All responders will receive proper attribution. 
Thanks;
joe b.
joeb33050@yahoo.com
  
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DonN
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Re: Bullet weight info needed
Reply #1 - Dec 20th, 2004 at 8:53am
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Joe
I shoot a .40 cal and my results are much the same as yours. Although my bullets are 100gr lighter.
I use a P. Jones mold and the bullets cast out about 422 grs.
The spread is much the same as yours that is +- one gr. With some (when the mold is coming up to temp) lighter and some heavy (if the pot temp gets away from me).
If I was seperating your bullets I would use all the bullets that weigh 524.4 to 525.0 then seperate them into two lots 524.4 to 524.7 and 524.8 to 525.0. 
I read somewhere in a Sierra ad that there Match King bullets are keep to a +- .3 grains in weight.

Don
  
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PETE
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Re: Bullet weight info needed
Reply #2 - Dec 20th, 2004 at 3:57pm
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Joe,
  I'll even do you one better. Below is a test I did several years ago when several of us on BP-L got to wondering if the pot lite, going on or off, would have any bearing on wgt. variations. The following should be self-explanatory.

PETE

  Bullet is the Lyman 457125

------------------------------------------------------

The casting session is normal except for the following. ALL bullets are in
the test. This means I did NOT discard any at the beginning of the test. I
usually throw back 10 or so to get the mould hot and get my technique
smoothed out for the session. All visual rejects are also left in...
something I would normally throw out. They will be marked! About halfway
thru I fluxed the pot again to throw in a non casting time period to see if
that had any influence on the results. When I do flux during a session I
will discard about 5 or 6 before keeping any. This line will be noted in the
test. Normally I quit casting when the pot level is about 2/3rds empty. I
like a full ladle to pour into the mould so usually quit there. This place
is also marked. This time I kept going till I got two visual rejects, or, I
just could'nt get enuf lead into the ladle to fill the mould. The latter
happened first.
  An interesting aside.... Maximum temp. of the pot was 860 degrees F. at
the beginning of the session. When the pot was down about a 1/3rd the temp.
came up to about 880 degrees F. When the pot reached the halfway point the
temp. stood at 890 degrees F., and stayed there till I quit. You can make of
that what you will.
  Casting session lasted an hour an fifteen minutes.
  Average of ten randomly selected bullets was 523.8 grs. With my .5 gr. +
or - acceptance allowance this will put the bullets I keep out of this
session at 523.4 grs. to 524.3 grs.
  So without further ado:....


   X = pot lite on
   0 = pot lite off
   VR = visual reject
   WR = weight reject


       520.4   WR      VR
       521.0   WR      VR      X
       522.4   WR      VR
       523.5
       523.7
       524.5   WR
       524.6   WR
       525.4   WR
       525.3   WR
       524.8   WR              0
       524.7   WR
       524.3
       523.7
       524.3
       524.2
       524.3
       523.9
       524.3                   X
       524.2
       524.1
       524.3
       523.8
       524.0
       523.7                   0
       523.8
       524.3
       524.2
       524.2
       524.3
       524.1
       523.9                   X
       523.5
       523.5
       523.9
       523.3   WR
       523.7
       523.5                   0
       523.7
       523.9
       523.8
       523.8
       523.9
       523.7
       523.8                   X
       523.9
       523.3   WR
       523.9
       523.9
       524.1
       523.9                   0
       524.1
       524.0
       524.0
       524.0
       523.6
       523.5
       524.0
       524.2                   X
       523.7
       524.0
       524.3
       523.2   WR      VR
       523.8
       524.1
       523.6                   0
       523.9
       522.4   WR      VR
       524.1
       523.9
       524.1
       523.8
       523.9
       523.7                   X
       523.8
       523.7
       523.9
       524.3
       523.6
       523.1   WR      VR
       524.1
       524.2                   0
       523.9
       523.7
       523.9


                70 SECOND BREAK TO FLUX THE POT. NORMAL PROCEDURE FOR ME.


       524.5   WR
       524.2
       523.9
       523.9
       523.9                   X
       524.0
       524.1
       523.8
       523.7
       523.8
       523.9
       524.2
       524.0                   0
       524.0
       524.2
       524.1
       523.1   WR
       523.5
       523.8
       522.9   WR
       523.3   WR
       523.1   WR
       523.5                   X
       523.4
       523.7
       523.5
       523.2   WR
       523.5
       523.8
       523.7
       523.5
       523.0                   0
       523.7
       523.9
       523.8
       523.4
       523.8
       523.0   WR
       523.8


               THIS IS WHERE I WOULD NORMALLY STOP THE SESSION


       523.6
       523.6
       523.6                   X
       523.6
       523.2   WR
       523.4
       522.7   WR
       523.3   WR
       523.5
       523.2   WR
       523.6
       523.4                   0
       523.4
       522.4   WR      VR
       523.5
       523.5
       523.7
       523.1   WR
       523.1   WR
       523.3   WR
       523.2   WR
       523.4                   X
       523.4
       523.3   WR
       522.9   WR
       523.4
       523.3
       523.4
       523.7
       523.6
       523.6                   0
       522.7   WR
       523.5
       525.3   WR      VR
       523.9
                       END OF TEST


   In a regular session the VR's, or visual rejects, would'nt have made it to
the weighing session. The first ten would have been automatically rejected,
and I would have discarded 5 or 6 after the second fluxing, and I would have
normally stopped where I stated.
  
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DonN
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Re: Bullet weight info needed
Reply #3 - Dec 20th, 2004 at 7:36pm
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Joe and Pete
I usually cast 250 bullets at a session usually stopping every 50 bullets to fill the pot and flux and take a coffee break. I have found that as the lead level goes down in to pot it's more diffcult to maintain a constant pot temp so I fill after 50 bullets. And weight the bullets in the order cast.

I keep the bullets on a bullet board in the order cast. I try to keep the pot temp. at 770 to 780deg.

When I'm weighing the bullets I will see a difference in weight caused by pot or mold temp changes.
When I first start casting if the mold temp is not right. Bullets are light from .2 or .3 gr. up to 1 or 2 grs
If I have a bullet hang up in the mold for more then a couple of seconds. The next bullets will be light from .1 to .5 gr or more if the hang up takes a long time (+ 30 sec.) to clear. The next couple of bullets may also be light.
If the pot temp. gets away from me and goes up the bullets get heavier. 790 deg can add .2 grs or more
If it goes down the opposite happens.
The next time you cast keep the bullets in order. It's very enlighting to see what happens to the bullet weight when the mold or pot temp changes. I gets to the point you know the bullet is going to be light or heavy just by an interruption in the casting routine or the pot temp changes.

I've also found out if I cast at 770-780 deg. most bullets will be 422.0 to 423.0 grs. If I cast at 750-760 deg. most bullets will be 420 to 421 grs. 

By the way if every thing is working right the weight will be within -+ .1 gr. In fact some string of bullet will weigh the same. 
Don 
 

  
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joeb33050
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Re: Bullet weight info needed
Reply #4 - Dec 21st, 2004 at 7:38am
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Pete's info is sort of what I need, numbers rather than words. I'm writing an article about variation in bullet weight during a casting session, hence the need for numerical data. I don't cast many 45 bullets down here, longest range is 100 yards. Thanks, and please send that info.
joe b.
  
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PETE
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Re: Bullet weight info needed
Reply #5 - Dec 21st, 2004 at 2:21pm
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DonN,

  I'll refer you back to the test message above, in case you didn't catch what I was doing. The mould was set on top of the pot shelf provided for the purpose as the alloy was melting. After fluxing for the first time the casting began, and what you see in the test are the bullets in the order cast, from the very first to the last with no rejecting any. As noted I normally throw back the first ten or so bullets, because as the test showed, they will not make the wgt. tolerance I calculate for each batch I cast. Each batch is one pot full, or one session, because I've found that adding more alloy tends to change the average bullet wgt. even when run at the optimum rate.

PETE
  
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PETE
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Re: Bullet weight info needed
Reply #6 - Dec 21st, 2004 at 2:31pm
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Joeb,

  Here's another test that I ran about the same time as above. A question was raised that you ought to take the top 60% of your casting session and reject the rest. The below is where I'll pick up from a rather lengthy post on this.

  To clarify what you see..... The number at the left is the lightest bullet I found in the casting session. I increased this number by .1 gr. until I got to the heaviest bullet in the lot. The number on the right is how many bullets fell on that wgt. As you can see some numbers didn't have any of that wgt. The rest should be self explanatory and if you care to plot it out you will get a pretty good Bell Curve.

PETE

-----------------------------------------------------

  As a caster I don't tend to think along those lines exactly. For bullets
over 400 grs. I'll take an average of the whole lot and go up or down 1/2
gr. from that and anything falling outside that I'll reject. As the bullets
weigh less I tighten up my criteria till they get to below 100 grs. I won't
except any variation. I don't recollect ever having done a bell curve on a
lot to see just exactly how they do fall.
  Chris is right when he states there probably should'nt be any bullets over
your spread limits, but as you'll see in a bit, this does'nt hold
true.....at least for me.
  I think it was Marc that did this before but I think that there are enuf
new people on here since a year ago that it could bear repeating.
  What I did was to run a lot of 120 Lyman 457125 bullets and weigh them.
That's about all I can get out of a 20 pd. pot comfortably. I fluxed once at
the beginning of the session and that was it. I next selected 10 at random
and established a base line of 523.6 grs. A 1/2 gr. above and below that
puts the range I'll except at 523.2 to 524.1. Here's how the whole lot came out.


    522.6 - 1
    522.7 - 0
    522.8 - 0
    522.9 - 0
    523.0 - 1
    523.1 - 2
    523.2 - 9   lower limit
    523.3 - 9
    523.4 - 15
    523.5 - 25
    523.6 - 17
    523.7 - 13
    523.8 - 14
    523.9 - 4
    524.0 - 3
    524.1 - 2   upper limit
    524.2 - 0
    524.3 - 3
    524.4 - 2
  
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PETE
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Re: Bullet weight info needed
Reply #7 - Dec 22nd, 2004 at 10:23am
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Joeb,

  Here's another run of bullet wgt.'s like you wanted, since you don't seem to be getting much response on here or over on MSN's BPCR.  Smiley I will agree with some of the comments over there about wgt. not being all that critical.

  I'm sure we've all found that shooting the foulers produces groups that are as good as those from carefully selected bullets. One of the reasons I weigh bullets is so that I can separate out those that don't seem to fit a norm, suggesting there is something not right with them. This will show up in the following rather nicely.

  The bullet for this run is a Lyman 311334 GC that I plan on using for the CBA Postals this coming Summer. The run consists of 100 bullets randomly selected out of 2000 and are cast out of 50/50 Lino/WW's. The data is set up exactly like the last message I posted.

192.0 - 1
192.1 - 1
192.2 - 0
192.3 - 2
192.4 - 13
192.5 - 15
192.6 - 19
192.7 - 13
192.8 - 15
192.9 - 15
193.0 - 5
193.1 - 1

As you can see the majority fall within a .6 gr. spread and that's what I use for this wgt. range bullet. The 4 on the low side and the 6 on the high side would be thrown back into the pot. When I shoot these bullets I will shoot them in the wgt. order above so normally no one group/score is shot with any bullets that have a difference in wgt. of more than .1 gr.

  Some will say that this is being pretty finicky, but as with most other things in shooting, a lot of it has to do with the mental game. Doing it this way makes me happy!  Smiley

PETE
  
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40_Rod
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Re: Bullet weight info needed
Reply #8 - Dec 30th, 2004 at 5:13pm
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Joe 
Here is the results from a short casting session. The mould is a Brooks .40 in Cabin Tree mould handels.  The aloy is 32 : 1 lead to tin. The mould is set on the pot rim to warm as the aloy melts. When the aloy is at temp. (760) I start to cast. I cast 12 bullets and check for weight. If my weights are in the correct range I start to keep what is cast. This is the results.

433.8          434.0          434.4
433.8          434.1          434.4 -
433.6          433.4          433.5
433.8          433.8          433.3
434.1          433.8          433.6
434.3          434.1          433.7
343.1          434.1          433.5
434.0          434.3          433.7
434.0          433.9          433.7
434.2          434.0          433.6
434.1          434.2          433.2
434.3          434.7 -        433.7
434.1          434.6
434.1          434.5
433.9          434.5
433.9          434.4
434.2          434.4
434.1          434.6
434.0          434.7
433.8          434.7

When I discovered that my bullets had gotten heavier I went back and checked my closing tention. It was loose When I tightened it back up the bullets came back down to the right weight range.
  
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