Gas checks & tensile or shear strengths

[OnHoPr]

I suppose with the GC crimped on and for example 35,000 psi on the base of the boolit, it would be hard for the GC to rotate on the boolit's base. I see where the rifling marks on GCs from recovered boolits. The GC is usually made of copper, aluminum, and such. So my question is, besides the GC protecting the base of the boolit, is there any statistical data on how it supports or adds tensile strength or shear strength to the boolit?

[DukeInFlorida]

Tensile strength or shear strength isn't really why the check is there. I would think that from that perspective the difference would be almost non-existant.

The OD of the gas check, during sizing (gas check placed on boolit before sizing), gets sized to the same as the OD of the boolit. The gas check shank, when designed properly, should grip onto the inside walls of the gas check very firmly, especially after sizing is done.

So, no rotating of the check separate from the boolit. And, when the shot goes of, you have a LOT of pressure pushing the back end of the gas check cup only the base of the boolit. Again, that would also tend to create enough friction on it's own to keep the check in firm (non-rotating) contact with the boolit.

Finally, gas checks are made these days from copper or aluminum, either of which are just slightly harder than the lead. And, the cup walls are thin enough that I don't think they affect/change/contribute anything significant to the strength of the boolit.

What would you want to do with a boolit where any of that would be a concern?

I'd think that you'd be better off analyzing the strength differences in changing the lead alloy/composition.

The gas check is there to make up for the lack of science for the combination of:
* boolit sizing
* boolit hardness
* boolit lube.

[Sonnypie]

I think you are over thinking the powder on the babies bottom. :razz: