Greenhill question

[Razor]

In another post ('Nother plinker) I remarked that at 50 yds, the Pedersoli boolit I was using
in my IAB Sharps, was slammin' into the target SIDEWAYS !!!!

I got a helpful email from a feller suggesting my boolit was too long. (Thanks Hib  )

I did a 'google' on Greenhill and determined that my bullet length for a 54 caliber, 1:60 twist,
needed to be .75" OAL. (my boolit is 1.062" )

My question is :  Am I correct    Did I do this right
I need to get some 3/4 inch long boolits

[Smokin_Gun]

Pedersoli's 1862 called the Confederate Carbine is a 1 in 48 twist... the Mold that they sell at Track of the Wolf I I think it is are long boolits , longer than the original .75" long .54xx that are pointed maxi type boolits. I measured my Armi Sport '59 Sharps and got .550" X .535" on the lands and grooves. Some .540" maxis I got went right down the barrel. I got a rapine Mold Site and boolit chart but can't find a Dealer that sells um.

http://www.dixiegunworks.com/product_info.php?products_id=12258

http://www.ch4d.com/catalog/?p=88

http://www.manta.com/coms2/dnbcompany_ggmdkt

I think the boolit was no as much too long maybe but rather it may have been bouncin' around in the barrel not bein' large enough to engage the riflin' proper. I'm still workin' on gettin' the right size mold. Measure your bands then the lands and grooves...mine is easy it has 6 of each...does yours have 6 or 7 lands and grooves?

SG

[Smokin_Gun]

Razor your IAB is 1-48", Pedersoli Sharps is 1-48, my Armi Sport is 1-22" ... I gotta refigger that now...

http://www.fcsutler.com/fcweaponscarbines.asp

SG

[Razor]

Hey SG...

Before I go ordering another mould, like I mentioned, I wanted to try paper patching  first...
I was kinda thinking 'bout the same thing..that the boolit was just rattlin' down the bore..
My IAB is a 7 groove, so my slugging measurements are close, but not exact..
Somewhere, I read that my IAB twist rate was 1:60
I'm gotta go measure it myself..
If'n it is 1:48, that is very close to the Greenhill figure of 1:43 / 44 .....
So, that would point even more strongly to the boolit being of undersized diameter.
Thanks for pointing the twist rate out.

[Razor]

My twist rate is as SG says...1:48

DGW:

The blued 54 caliber barrel is 29" long tapered round 1.225" at breech to .812" at muzzle, button rifled .005" deep, 1-60" twist, 7 lands measure .540" and 7 grooves measure .550".

Thanks for prompting me to double check...

[hepburn45110]

Since when did a Sharps become a muzzleloader?

[Dryball]

It isn't one, but it fits in quite well with our loose definition of muzzleloader as it uses blackpowder and percussion caps, and was a very important weapon during the last days of the true front stuffer. It is not kin to the modern inlines as it uses an outside, separate percussion lock.

Ned

[Smokin_Gun]

I don't know who Greenhill is but I haven't found any Sharps Carbines with a 1:60" twist. He may be refering to an IAB Sharps Sporting Rifle... Dixie Gun Works #PR0402 with a 1 in 60 twist 7 lands and grooves, 29" bbl.
What's the actual drive band diameter on them Pedersoli Sharps Boolits?

SG

[Razor]

Yup..Sorry..IAB Sporting rifle....29" barrel
Pedersoli boolit drive band measures  .540"
Measuring more carefully, and 3 more times,  the rifling seems to be 1:60 after all.

One of the first persons to try to develop a formula for calculating the correct rate of twist for firearms, was George Greenhill, a mathematics lecturer at Emanuel College in Cambridge, England. His formula is based on the rule that the twist required in calibers equals 150 divided by the length of the bullet in calibers. This can be simplified to:

    Twist = 150 X D2/L

    Where:
    D = bullet diameter in inches
    L= bullet length in inches
    150 = a constant

[jackson]

Razor,

I own a Sile Sharps 1863 pattern carbine and an Armi Sport 1863 sporting rifle I bought from Taylors. Since my IAB Sile Sharps was made
back in 1977 it has a different bore size than todays IABs. There is a big difference between the Pedersoli bores and the Armi Sport barrels.
According to a post on the NSSA bulletin board, the Pedersoli sharps bullet mould is too small to effectivly and accurately shoot in the larger
bore size of the Armi Sport Barrels. Thus Rapine makes two different (christmas tree style) sizes of the same mould. NSSA said the larger
of the two shoots way more accurately in the Army Sport Sharps firearms. I was given some of the Pedersoli cast bullets to shoot
and found them sorrily undersized for my Taylor sharps. You can see the problem if you place the point of the Pedersoli bullet into the muzzle
of your sharps. This will show how ill fitting it is. Only the last ring of that bullet engages the rifling. The other rings will just bounce around the barrel when
shot.

I am having fun shooting the Lee oversize .540 minnie ball in my Armi Sport Sharps. I make my own paper cartridges and have the minnie ball seated
at a depth where when It is inserted into the breech it starts to enter the barrel. Shoots very well and no key hole prints on target.

One of the biggest problems with shooting many of the Sharps replicas is breech block fowling. Original Sharps made firearms did not have this
problem as the breech block area was made to tight fitting tolerances. Some one in the NSSA came up with an O ring conversion for loose fitting
sharps breech block which allows you to shoot 50 -100 rounds before any cleaning is need to the breech block.  I tip my hat to those NSSA guys
for making rocket science out of shooting black powder firearms.