Home Forums Hunting & Shooting Ask The Gunwriters Very Old bullets - "softer?"

I was reading some articles published by the excellent "Ballistic Studies" folks in New Zealand. The author mentioned something that I had never read before. He claimed that very old bullets (stored for a few decades) may have changes to the core or jacket that cause the bullets to expand quicker / fragment more. Can this be verified? What would be the reason? Is it a significant difference?

I have quite a few bullets in my reloading stash that were purchased from estates and such. Some, like the 7mm 175 gr. RN are a style not easy to find since most manufacturers have dropped that style, but my 7x57 shoots the old style heavy RN bullets best. Same with some of my .375 bullets, 9.3's and some .308" too. Makes me a bit wary of using those old bullets on game.

What is your experience?

I suggest writing to the Ballistic Studies people and asking them for their proof sources. Without actual testing to prove his claim, I have no opinion either way. I do know that cast bullet companies have long talked about hardening cast bullets and how that hardness changes over time. There are many differences in the lead alloys used for cast bullets and the core of cup and core bullets so the possibility of age hardening/softening will be different.

Beartooth quote From “Beartooth Bullets’:

“Since Beartooth Bullets Are Heat-Treated, Do They Age-Soften? :: By on 2001-01-29

“Beartooth Bullets are indeed heat-treated. We heat treat our bullets to a BHN 22, and over the course of 18 months they will age-soften to a BHN 21, where they will remain stabile indefinitely.
We have very carefully and intentionally chosen our alloy with a target BHN of 21 in mind. When heat-treated to BHN 22, the alloy only loses one BHN point when stored at normal room temperatures. This means that the load you work up today with our bullets will perform the same several years from now when stored under normal circumstances. Our bullets will not ever get softer than BHN 21, from aging or storage.”

There is a lot of information on cast bullet hardness if you do some searching for it.

He doesn't impress me. Dude says all kinds of stupid, unverifiable stuff like certain proven cartridges and bullets have very slow wounding and death at 250 yards. All of us have seen it and done it. I don't need his opinion to know things work or don't work.

He is probably wrong on this one too. Metal doesn't much care how old it is, as long as it wasn't heated or used in the meantime.

I don't know about all that. But I generally like to read his stuff