100 yards will be about it forpretty much anyroundball. Perhaps 125-150 yards dependng on the load, but I would practice at that range to become proficient. Also they can be accurately shot out to 1000 yards, the sighting required to do so is not your typical open hunting sights.Roundball'sloose velocity and energyvery rapidly after being fired. The other problem you will run into with open sights is target obstruction. You cannot accurately see the target much past 100 yards and with some sights 100 yards is questionable.

58 caliberPRB would be significantly more lethal than a 54 ballet.

As to how fast an Elk will drop is variable. Animals do strange things when the are shot. Some will fold up when only nicked, others will run forever after being shot to pieces.

If your shot placement is text-book (top of the heart to sever all arteries) then perhaps the beast will drop where they stand. But if you are off slightly and only wound or missthe heart, then they can run quite great distances.

On the other hand, a classic double lung shot could have them running 100+ yards or much more or dropping where they stand. A shoulder shot with a PRB at 100 yards range could result in a wounded and lost animal or they could fold up where they stand.

For practice to be able to take the heart shots which have amont the highest chance to drop an animal the quickest, you should be able to routinely print groups at least 6" preferably 4" or less at 100 yards.

If you cannot routinely shoot groupsinside of 6" at 100 yards, then you really and ethically should not be hunting at that range. This is true regardless of what you are shooting.

Also you should be loading the maximum allowable hunting loadfor your rifle that still holds accuracy to ensure 100 yard PRB effectiveness.

My opinion.

Tahquamenon