Boolit diameter

[Mark Thomason]

I have read that boolits should be cast to the groove diameter, or to that minus .002 or so. However, Sharps and some other fine rifles were made to chamber boolits of bore diameter. I have read that some cap and ball revolvers should be loaded with balls of more than groove diameter. The original Sharps used Christmas tree boolits, the forward ring of bore diameter, the bottom of groove diameter, and the middle ring halfway between. So, I have read just about every answer to the question of proper boolit diameter. I am guessing there is an explanation in which all of this makes sense. Can anyone enlighten me?

[docone31]

Welcome Mark.
Great folks here.
I am by no means an expert.
I go .002 over groove.
From what I understand, black powder explodes, bumping up the effective diameter of the boolitt, making the seal.
With cap and ball revolvers, the oversize ball gets shaved down on loading to diameter providing a bearing surface for the rifleing on firing.
I am sure others will definately pipe in here, quite a few are Sharps lovers, and lots have cap and ball experience.
They will fill you in for sure. I have followed their advice and gotten positive results.
You asked some legitimate questions. I am going to learn from this thread also.
Welcome.

[runfiverun]

the sharps you describe is a tapered boolit the design is still used today.
it fits in the throat and if the throat wears or is worn you can seat the boolit out a bit further to still fit it.
this also eliminates the bore rider by engaging the rifling progressively till you have a full bore.
you also have a lot of bearing length and the lube capacity you need.

[Le Loup Solitaire]

Hi, In the book titled "The art of bullet casting" (a text currently still available) this topic is well written on. Among the various well known authors represented in this text someone described the controversy as a subject for "atheists and satan worshippers". Whatever the religious implications may be, the bottom line is that different people believe different things. One opinion is that good bullets come from a good mold to start with....and the best shooting is done with bullets that are shot "as cast". A second opinion is that sizing damages a bullet; the more the sizing-the more the damage done. A third opinion is that a bullet needs to be of "bore" size....bore in this case meaning groove. This would necessitate knowing what the measurement of the groove to groove diameter distance is in a given weapon, so it would be necessary to "slug" the bore to find out what it is. It is also known that upon ignition that the bullet obturates or upsets and fills the bore, but accepted practice is to have the bullet at-at least bore size or .001" over. The reason for this is primarily to allow for "gas cutting". This is all pretty sensible stuff and easy to work with. The problem however begins with the mold makers, most of whom, over the years, have found that allowing "mold cherry cutters" to run longer(and thereby requiring less sharpening and less being replaced) resulted in less expense. The result then of course is oversize bullets that then in most cases have to sized. When carried to far it becomes ridiculous. Buying a mold for a .30 cal rifle that has a groove diameter of .308....one would think requires a mold that drops bullets of that diameter or .309. But when you find that the mold you bought produces bullets that cast .312-.314" or more, then you have no choice but to size them down. Admittedly lubrisizer machines of this day and age are of better quality than those of years ago so they don't damage the bullets quite as much, but the line of BS about "you have to size the bullet down, and that makes it shoot better.....is just that-- BS!!! The parameters that I have outlined above at the beginning of this discussion are some basics that have come from others who were pioneers in this world of cast bullets. It is what they established through experimentation and believed to be sound judgement. I suppose then what it really is about is what you and I choose to believe. I would recommend to you the book that I mentioned above. It is a classic and a wealth of information on cast bullets/casting and you will find it very interesting. LLS

[EDK]

The christmas tree boolit was used in percussion sharps breech loaders in paper cartridges. The cartridge paper is rolled like a cigarettte and tied to the smaller diameter base of the boolit. Tolerances weren't very tight...and the war of northern agression encouraged "close enough for government work." Mike Venturino found an original SHARPS civil war carbine AT A YARD SALE, IIRC, and did one of his usual well researched articles on the quirks of the gun and making paper cartridges.

When blackpowder was the only propellant, the bore diameter boolits would slug up to fit the grooves. Also, paper patch fans will argue about the appropriate diameter for the patched boolit...anywhere from "bore size minus" to"groove size or larger" and everything in between. There have been some articles, again refer to MLV, about chambers of antique rifles that would not accept groove diameter boolits.

When you research something like this, there is a lot of information. AND when you get to specific fire arms, there is usually some good reasoning...at that time....for what was done.

:cbpour::redneck::Fire: