Hey all,

I know I've had a lot of questions lately but do appreciate all the help.
I've always used .459 for my loads on my Pedersoli RB and just continued using the same on this new Sharps.  I was told .459's for the RB by someone on another forum, so I never questioned it.   
I'm just wondering if I should be loading .458's or continue with the .459's?

Thanks,
Andy

I'll agree with Paul in part. However, when using BP in the 45/70, the bullet can be smaller than groove diameter.  Especially a soft bullet. BP will bump the bullet expanding it into the grooves.  Speaking strictly for myself and no one else, I have had better luck with groove diameter or slightly undersize bullets when using BP. 

I was recently told by a very knowledgeable expert on the subject, that I have been giving posters bad advice on this forum.  What works best in my rifle may not work best in your rifle.  

                              Joe.  

I'm with Joe and Boats too.  Your bullet will bump up to the size of the chamber at the neck minus the wall thickness of the brass and then be squeezed back down as it goes through the bore.  What I've found out to be important is getting the bullet centered up in the bore before the trigger is pulled.  If you're shooting a bore rider and blow tubing, keep the nose about .002" under bore diameter.  If you're wiping, keep it at bore diameter and if your not shooting a bore diameter bullet, have your front driving band reduced about .004" and then seat it out so it will center up in the leade.  Bob

Hey mtnwinds, 
With a groove diameter of.458, the .459 bullets should be the right choice, correct?

OK, here we go:
* Been told, Pedersoli cuts all their 45-70 rifle barrels for the Sharps & Rolling Blocks to the same 1:20 twist at 450 - lands and 455 for the grooves.  My two 45-70's are 454 and 455.  My Rule of Thumb is 0.003 over groove diameter.  Have even shot 1:20 alloy & WW w/ 1/2% SN that are 0.460 with no adverse accuracy at 1000yds.  I'll leave it there for your choice.
Have to remember, store bought bullets are going to be 459 or 460.  I cast mine and these are the only ones that drop under 459:
Lee 405HB      45-70      1:20      456
Lee 459-500-3R      45-70      1:20      457

The rest of the 21 bullet types/alloy are 459 or 460 as cast.  So if your going to use 0.003 or under base diameters then you'll need to resize them.  IMO, the best die is the Lee Lube/Resizing Dies that are bottom push and do not twist the axis of the bullets as does the Lyman H&I dies 

Good Luck and Hope your shooting Black Powder only!

A few years ago I read so much conflicting information that I decided to take a cerrosafe cast of my chamber & the first couple inches of the barrel.  I ran a heavy cotton patch down my barrel from the muzzle & left in where I needed it to be to act as a plug and stop the casting.  Having removed the forearm & breech block (just in case I spilled some) I heated the chamber area plus a couple of inches ahead of it until it was fairly hot.  Meanwhile I was melting the cerrosafe in clean empty tuna can one portion of which I had forged into a small pour spout.  
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I had also jerry rigged a small funnel & placed it in the mouth of the chamber.  With the chamber area hot & the cerrosafe melted (double boiler set up) I picked up the tuna can with a pair of small vise grips & poured it into the chamber.  Lucky I guess...no spills.  I poured enough till it formed a sprue & then I let it cool which it did very quickly.  Ran the rod back into the barrel & pushed the cast out. This is what I got.  The funnel is what you see sticking out of the cast. You can see the chamber, leede, freebore, & the full depth rifling.  The very end of the chamber is .485", end of the leede is .470" and groove diameter from the beginning is .458" & also .458" 2" up the barrel.
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Now I could lay a case and a bullet against the cast & see exactly what the 'lay of the land' was like.  My patched bullet is swaged in a press and die made by Richard Corbin.  I apply the patch dry using Bienfang tracing paper.  I then dip the whole thing in water and gently twist the bullet while rolling the end over.  When dry the bullet mics exactly .450" and is a snug slip fit in my bore.  Breech seated, my bullet's base is right at the end of the leede & start of freebore.   (You need to Login or Register to view media files and links)