The real experts are over on the north-south-skirmish-site. 
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It may resolve itself in to a question of tolerances.

Minie ball molds come in several diameters, weights and profiles. Also thick skirt and thin. You will need to start with a ball that just enters the bore--a slip fit piston like entry is where you want to be. A 45-60 gr. load is all that's needed. 
kw

Have to decide how you want to use the rifle. During the war only concern was will it work. Today you can tailor the Minnie Ball to suit the gun and purpose. Have narrowed it down to two molds. Original Minnie from a Lyman mold and a “trash can” from a Lee mold. Trash can is lighter & larger. Flat nose punches holes in paper better, bore needs to be wiped often. Bullet was designed for reinactor competiton.

The Original style is more difficult to cast. Removable base plug will cool faster then the mold causing rejects on base wall condition if you don’t pay attention.  It shoots all day without wiping. Ram rod starts to go down hard base scrapes the bore and she goes back to easy loading. 

I don’t know if the larger better fitting Trash can is any more accurate. Mine (custom American built reproduction mix of original parts with a modern barrel) is a 4 moa rifle. Never been shot off a bench, 50 yards offhand no obvious difference. 500 yards the 585 gr original shoots to the leaf sight. Trash can won’t.  Strikes all around a 55 gallon drum at 500 & sometimes hits it.  Battle rifle massed fire at that distance it must have been a very effective weapon.

Boats

One of the CW shows in Richmond I bought the cleaning rod reinactors  actors  use. It’s large diameter Aluminum with a large file style handle, Delrin tight fitting bore bushing and tight fitting Delrin plug jag. It’s fast and very effective.

Anybody wants to make one I can take the dims off mine for you.

Boats

60 grs of 2 F is what you want. However I was told the Trash can bullet worked best with 40 grs of 3 F. Not surprising, Cowboy action shooters use powder puff loads too, short range speed events.

Want to see a Trash can look at Lee’s 575-472 & 578-478

Boats

Jack did not mean to sound negative on “Powderpuff” trashcan Minnes. Silhouette shooters that need knock down at distance coined that term & Silhouette large part of my experience .

Trash can as shot by NSSA is a very good target bullet. Original Minne is very effective at distance. Combination the two good plan.

Boats

boats wrote on May 6^th, 2020 at 7:24pm:


No worries on the "powderpuff" thing. The guys who really do shoot that type of ammo are the cowboy action guys.

The thing most folks don't understand about minies is that they have a "range" of powder charge where they are most accurate. All that stuff depends on powder, lube, skirt thickness, etc as to whether any given rifle will shoot any given minie.

The "trashcan" is an outstanding 50yd bullet as is the full wadcutter in a 38special. It also is a great hunting round within limits. 400gr soft lead at 1kfps will leave a mark duct tape and bandaids can't fix. Much past 75yds, it can start to get unstable.

One of my "distance" bullets is the RCBS Hogdon, but it isn't consistent to the point I fully trust it for competition if there's any wind. The Lyman 575213 is over 100gr heavier and is much better in that aspect. I have that mold but it drops at 581 which isn't a problem for me as both my 62 Colts need a 579ish bullet.