Cast bullet weight dropped

[Bobtorre]

I changed my alloy to pure Linotype and my 500 gr cast bullets dropped to 470 gr.

I don't understand. ?

[truckboss]

If your other alloy was pure ,you now have less lead and more antimony and tin.In the heavy boolits this is more prevalent:Fire:.

[Charlie Two Tracks]

Yup, that's what happened. Are you sure that you need a boolit that hard?

[Bobtorre]

It is a 45/70 and I am pushing it to close to 1300-1400fps. It is gas checked.

How do I fix it? How do I add more antimony to get the right weight?

[runfiverun]

weight is not the issue i don't even know what many of my boolits weigh.
i push a 1/3/96 alloy to over 1600 in my 45/70.
you can make this alloy by using 1 part lino and 3 parts soft lead.
it air cools to about 11 bhn and waterdrops to 18-20 bhn.

i do know what the diameter of them are though.

[243winxb]

Bullet Sizes & Weights – How to Vary Them

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


Quote:
The bullet diameters and weights presented in this list
are based on the use of Taracorp’s Lawrence Magnum
bullet alloy (2% tin, 6% antimony, 1/4% arsenic,
91.75% lead).
Bullet diameters and weights will vary considerably
depending on the lead casting alloy used. This variation
can be as much as 1/2% on the diameter, and 8% on
the weight among the most commonly used casting
alloys. For example, a .358-158 grain bullet might
show a diameter variation of .002", and a 13 grain difference
in weight.
Of the most commonly used alloys, wheel weights (.5%
tin, 4% antimony, 95% lead) will produce bullets having
the smallest diameter and heaviest weight, with
such bullets running approximately .3% smaller in
diameter and 3% heavier than bullets cast with
Taracorp's metal. Linotype will produce bullets with the
largest diameter and lightest weights. This alloy will
produce bullets approximately 1/10% larger and 3%
lighter than Taracorp. Other alloys of tin and antimony,
with antimony content above 5%, will produce bullets
with diameters and weights falling between those cast
from wheel weights and linotype.
Alloys containing little or no antimony will cast considerably
smaller than wheel weights and in some cases
will produce bullets too small for adequate sizing.
Within the limitations given above, the weight and
diameter of a cast bullet can be adjusted by varying the
alloy’s antimony content.
The size and weight of bullets of a given alloy will also
vary according to casting temperature. Higher temperatures
will result in greater shrinkage as the bullet
cools, thereby producing a slightly smaller and lighter
bullet than one cast of the same alloy at a lower temperature

[10mmShooter]

The harder the alloy the lighter said bullet will be, the greater percent lead the heavier said bullet will be.

[MT Gianni]

You might need lino if you can push that bullet over 2900 fps. I would not want to be on either end of that load.

[454PB]

I have used an alloy of 70% pure lead to 30% linotype for 45/70 with good results, and if the boolit is gas checked, you're good to the 1600 fps. that can be attained with a 500 grain boolit.

[Bobtorre]

Thank you for all the replies. Very informative

[mdi]

Lead weighs more than lynotype...:-D