Hardness vs. lube req.

[Jim]

I had a conversation the other day with a gent that said the harder the cast boolit is, the less lube is required. He suggested that a boolit that is as hard as water dropped pure tin doesn't need lube at all as it's as hard as a jacketed and would not lead the barrel. I'd sure like to hear y'all's comments on this.

[Bass Ackward]

Hmmm. My copper bullets don't lead, but they still copper. Worse under certain conditions less under others. The win comes from copper being easier to remove.

Your advise can be very right if you know what you are doing or get .... lucky. Or this gentleman can be very wrong if you have poor conditions and lead.

A bullet that is hard enough (strong enough) to resist obturation encounters very little resistance to cause friction. But .............. look how many other variables are involved. Here are just a few. Bore condition, throat type and size, bullet fit, lube quality, etc.

So how can we answer you with any certainty. As soon as we say he's right you are going to produce an exception. If we say he is wrong, you will try it and it works. Your question is best directed towards Professor Gun. And his answer is going to be through trial and error.

[jonk]

I would think he's right, if conditions are ideal;but if you get any gas cutting due to a rough spot in the bore or slightly undersized bullet, I'd think that would lead still.

[45 2.1]

Softer gilding metal used for jacketed bullets runs 50 BHN and higher.

He suggested that a boolit that is as hard as water dropped pure tin doesn't need lube at all

Water dropped pure tin does not harden any past what air-cooled tin does and it is fairly soft. Pure lead/tin alloy doesn't heat treat either. I think you need to find out if he knows what he is talking about.

[Larry Gibson]

I had a conversation the other day with a gent that said the harder the cast boolit is, the less lube is required. He suggested that a boolit that is as hard as water dropped pure tin doesn't need lube at all as it's as hard as a jacketed and would not lead the barrel. I'd sure like to hear y'all's comments on this.

If that was the case a lot of us would be casting pure tin bullets and dropping them into water to harden them, now wouldn't we? As already mentioned there are a lot of variables. What I find "au contraire" is that harder bullets require more lube not less because we drive them harder. Other wise why have hard bullets? Also as mentioned tin does not get harder by water dropping or heat treating. Tin alone is as hard as it will get and doesn't come close to an copper/zinc alloy bullet jacket in hardness. But then what do I know...there's only one way to know for sure, as Bass mentioned, let professer gun answer the question. You could (because I'm not) cast up some tin bullets and drop them out of the mould into cold water, load them up with no lube and shoot them at say 800, 1500 and 2000 fps. That should answer the question.

Since the gent was actually correct in that you won't get an leading (pure tin so where's the lead?) please keep us informed how you get the tinning out. Sorry but I'd call "BS" on that gent.

Larry Gibson

[Lloyd Smale]

I would think in alot of circumstances a hard bullet needs a good lube as much as a soft. Part of the job of a lube is to seal the bore from blowby and that is needed probably more in a hard bullet then in a soft one. If your gun is specked perfectly an you used the righ alloy you might even get away with no lube but all the stars had better be aligned.

[454PB]

I tried it recently using BHN 26 boolits at 1100 fps. Leaded the barrel badly.

[Shiloh]

I tried it recently using BHN 26 boolits at 1100 fps. Leaded the barrel badly.

I'm not a bit surprised at what your results were. Ive accidentally shot non-lubed bullets at from a S&W 625 at 700fps and had bad leading. There is a reason that lube has been in use for a long time. As stated by Lloyd Smale, you may get away with it a time or two but not for long.

Shiloh

[Jim]

....same thing I do. I just wanted to run this guy's statements past y'all without "leading the witness". Hard or soft, I can't see running a softer(compared to the barrel) metal bullet down a barrel without some kind of lube to prevent galling and/or smearing. Basically, that's what it boils down to.
Unto myself, I've prooved that a light pass of an oily patch between shots improves M/V with jacketeds as opposed to shooting through a dry barrel. Soft lead, hardened alloy, copper jacket, they're all softer than gun barrel steel and will give up to some degree or other being forced down a tube that presents an interference fit.
Your Honor, we, the jury find the defendant guilty of blowing smoke.

Thanks, guys!

[Bret4207]

Blowing smoke for sure. There are just too many variables involved to make blanket statements like that one. Each gun is a law unto itself.