If the initial acceleration deforms the ball it will do it just as it starts to move. At any rate this is where bullets bump up in BPCRs.
This is shown when shooting a cartridge case that is too short for the chamber with PP bullets. The upset will shear paper from the bullet at the case mouth and it will often stay stuck to the case mouth. Finding the bullets will show exactly where this occurred on the bullet as a ring, knowing the seating depth tells the rest.
GG bullets will not often show this since the case mouth often is at a groove in the GG bullet.
Also over sized chambers will also give a hint. Since the bullet upsets to the extent the case will allow on ignition GG bullets in particular will have a fin at the base showing that the bullet was subsequently sized to the groove dimension. Since the bullets were near groove dia when loaded we know they expanded significantly if they are finned. This is not conducive to accuracy and chamber mouth dimensions that will work with smokeless will give hopeless patterns with conventionally loaded ammo with BP. Alloys as hard as 1:16 will expand but the harder alloy will prevent the nose from deforming. Softer bullets must have a very good nose design to prevent that area from slumping and causing the bullet to tumble from the concentricity being destroyed. I spent a lot of time on this years ago since at one time I wrote all the specs for Shiloh Rifle Manufacturing's non-SAAMI chambers. Everything that there was no factory ammo for at the time we had to write our own soec .
But RBs? I don't know about or at least cannot prove or disprove, just theory. Bigger, more likely, smaller less likely. The easier the ball moves due to inertia the less likely it is to deform significantly.
Rifling imprints...
If the ball is hard like WW even that have not been quenched it will not significantly engrave probably just a light cloth imprint (but these vary in hardness), since it cannot "squish easily. Softer balls are engraved to some extent by the rifling unless loaded too loose. If shooting a .535 in a 54 with a .018 patch it will engrave the lands through the patch rather heavily.
Hard lead works best in rifles with narrow lands, like Green Mountain and shallow rifling (for a PRB) of .008" or maybe .010. The old wives tale that only pure lead would work comes from barrels with deep grooves lands equal to the grooves or even much wider back in the day.
Some were even narrower than this.
Hard lead has been be used in MLs since the firearm arrived in Africa and India and hunters found that pure lead produces poor penetration on heavy game.
Hard lead, if cast in the same mould will produce a larger ball and will require a thinner patch than "pure" lead would.
People worried about the lead supply should pool resources with other shooters and order a ton more or less depending, then the worry goes away.
Brass or copper projectiles are not included in the above discussion.
If it reaches the point where one must order small batches of extremely expensive brass balls to shoot a ML then people will have bigger problems than where to find RBs for a ML.
Back in the early smokeless era Fredrick Mann found that even with jacketed bullets in a 30-40 bore sized bulets shot better and gave higher velocity WITH THE SMOKELESS POWDERS OF THE TIME. I do not believe this would work with todays rifle powders but the powders of the time were less progressive burning I suspect. For more information on bore sized bullets read "The Bullet's Flight from Powder to Target" By Mann, its been reprinted and should be available. He referred to lead alloy bullets at smokless pressure levels as "putty plug bullets" because of the deformation he observed.
But RBs were not part of his program.
Dan
This is shown when shooting a cartridge case that is too short for the chamber with PP bullets. The upset will shear paper from the bullet at the case mouth and it will often stay stuck to the case mouth. Finding the bullets will show exactly where this occurred on the bullet as a ring, knowing the seating depth tells the rest.
GG bullets will not often show this since the case mouth often is at a groove in the GG bullet.
Also over sized chambers will also give a hint. Since the bullet upsets to the extent the case will allow on ignition GG bullets in particular will have a fin at the base showing that the bullet was subsequently sized to the groove dimension. Since the bullets were near groove dia when loaded we know they expanded significantly if they are finned. This is not conducive to accuracy and chamber mouth dimensions that will work with smokeless will give hopeless patterns with conventionally loaded ammo with BP. Alloys as hard as 1:16 will expand but the harder alloy will prevent the nose from deforming. Softer bullets must have a very good nose design to prevent that area from slumping and causing the bullet to tumble from the concentricity being destroyed. I spent a lot of time on this years ago since at one time I wrote all the specs for Shiloh Rifle Manufacturing's non-SAAMI chambers. Everything that there was no factory ammo for at the time we had to write our own soec .
But RBs? I don't know about or at least cannot prove or disprove, just theory. Bigger, more likely, smaller less likely. The easier the ball moves due to inertia the less likely it is to deform significantly.
Rifling imprints...
If the ball is hard like WW even that have not been quenched it will not significantly engrave probably just a light cloth imprint (but these vary in hardness), since it cannot "squish easily. Softer balls are engraved to some extent by the rifling unless loaded too loose. If shooting a .535 in a 54 with a .018 patch it will engrave the lands through the patch rather heavily.
Hard lead works best in rifles with narrow lands, like Green Mountain and shallow rifling (for a PRB) of .008" or maybe .010. The old wives tale that only pure lead would work comes from barrels with deep grooves lands equal to the grooves or even much wider back in the day.
Some were even narrower than this.
Hard lead has been be used in MLs since the firearm arrived in Africa and India and hunters found that pure lead produces poor penetration on heavy game.
Hard lead, if cast in the same mould will produce a larger ball and will require a thinner patch than "pure" lead would.
People worried about the lead supply should pool resources with other shooters and order a ton more or less depending, then the worry goes away.
Brass or copper projectiles are not included in the above discussion.
If it reaches the point where one must order small batches of extremely expensive brass balls to shoot a ML then people will have bigger problems than where to find RBs for a ML.
Back in the early smokeless era Fredrick Mann found that even with jacketed bullets in a 30-40 bore sized bulets shot better and gave higher velocity WITH THE SMOKELESS POWDERS OF THE TIME. I do not believe this would work with todays rifle powders but the powders of the time were less progressive burning I suspect. For more information on bore sized bullets read "The Bullet's Flight from Powder to Target" By Mann, its been reprinted and should be available. He referred to lead alloy bullets at smokless pressure levels as "putty plug bullets" because of the deformation he observed.
But RBs were not part of his program.
Dan
