Size vs Weight for surface area and accuracy

[RegisG]

Now that I am alloying and testing hardness, there are more questions popping up. I understand that barrel/grove fit is most important for accuracy. BUT, if I cast a larger bullet with substantially increased tin, the weight will be reduced. Would a 120gr in a 158gr mold be more accurate than 120gr in a 120gr mold? In other words if I replace half the lead with tin in an alloy, the weight for any given size bullet will be reduced (by about 30% I believe). Weight vs volume difference: kg/cu.m 11340 lead vs 7280 tin.

Will the added length contacting the grove surface improve accuracy, or increase drag, or do nothing? There may be an obvious answer that I just don't know (other than cost).

Thanks,
Regis

[scottfire1957]

Sounds like you need to do some casting and weighing and measuring and shooting.

[Bzcraig]

The short answer is 'no' accuracy will not be better. I don't know if your hypothesis is correct but if it is, you would have a very long 120gr boolit thus unable to use 120gr load data and too light a boolit to use 158gr data. Tin is much more expensive than lead and there is nothing gained by increasing it beyond about 2/3%. Boolit fit and taking time to find what each gun likes is far more productive.

[scottfire1957]

The short answer is 'no' accuracy will not be better. I don't know if your hypothesis is correct but if it is, you would have a very long 120gr boolit thus unable to use 120gr load data and too light a boolit to use 158gr data. Tin is much more expensive than lead and there is nothing gained by increasing it beyond about 2/3%. Boolit fit and taking time to find what each gun likes is far more productive.



Yeah, what I said.

[RegisG]

Yep, the load data is a show stopper for me as I'm not able to create new (I just use published load data spreads).

Interesting but, not practical and maybe not possible.

Thanks
Regis


The short answer is 'no' accuracy will not be better. I don't know if your hypothesis is correct but if it is, you would have a very long 120gr boolit thus unable to use 120gr load data and too light a boolit to use 158gr data. Tin is much more expensive than lead and there is nothing gained by increasing it beyond about 2/3%. Boolit fit and taking time to find what each gun likes is far more productive.

[runfiverun]

the data part wouldn't slow me down a bit.
the globs of tin in the alloy would for sure make me not do it.

think about how tin reacts under stress and pressure now put it in a case and pound it with 30-k psi, and try to spin it in a real tight circle.