(1) Steel shot is 3 times harder than lead shot:

  (A) Hardness:
 Lets first examine the steel shot advantage by firing a shell and observe all that takes place within the barrel of a shotgun.
 (1) Upon ignition the shot pellets are compressed against each other deforming some lead pellets (not steel),
 (2) then entering the forcing cone, compression takes place further deforming some more lead pellets (not steel),
 (3) the next compression takes place in the choke further deforming even more lead pellets (not steel).

  (B) Pattern Performance:
 Steel shot is very hard so it stays round and flies truer to the target. At 40 yards, a much higher percentage of steel pellets will be on target than lead loads. At 60 yards, steel shot will yield an even higher pattern percentage as well.

  (C) Shot String:
 Lead shot, which is easily deformed upon firing, develops a relatively long, large-diameter shot string. Steel shot however because it is three times harder than lead, stays round, and develops a shot string that is 50-60% shorter and 60-70% narrower than lead.

  (D) Velocity:
 The reason that most lead shot hunting game loads average around 1350 fps on the high velocity side down to 1150 fps on the low velocity side is the fact that lead shot will deform easily and blow patterns.
 Steel shot has a very distinct advantage here it is very hard and the pellets or shot will not deform at all so the velocity can increase without shot deformation and blowing patterns. Steel shot hunting loads average 1500 fps on the high velocity side and down to 1265 on the low velocity side.

  Overview: Steel shot does not deform from the time ignition starts in a shotshell until all the shot has come to rest in a piece of game, therefore steel shot (as a whole in percentage) penetrates deeper than lead shot.
  Note: Penetration factor is based on the remaining round pellets that are left which will penetrate deeper than dented or deformed pellets.

(2) Steel shot is lighter than lead:

  (A) Pellet Diameter and Weight:
  Because all shot sizes are determined by the pellet diameter and not by weight, steel shot is disadvantaged in down range performance when compared to lead shot. To convert to steel you must make the conversion in pellet weight and not in size. If you take two pellets of the same weight and fire them downrange there is NO DIFFERENCE in their energy level until they reach 60 - 75 yards, then the larger diameter will start to give way to its smaller diameter counterpart and this is clearly maximum effective hunting distance.

  (B) Pellet Counts:
  Shot size in diameter measure in steel and lead are the same and steel weighs less than lead, so, it takes more steel pellets to make up a charge weight equal to lead pellets of the same shot size.

  (C) Lead Shot to Steel Shot Conversion Chart:

  (D) Choke Tubes and Ounces Of Shot:
 This again has to be adjusted as well, if a steel shot pattern is 60% to 70% narrower then this automatically tells you the pattern is to tight so the logical choice is lower ounces of shot and a more open choke are needed.
 The most effective combinations of choke and ounces of shot in all our tests revealed that 1 and 1/8 ounces of smaller shot (BB and down) fired at 1350 fps. through a stainless steel improved cylinder choke gave well above standard hunting pattern percentages.

  Overview: Steel shot has proven to us that when the conversion is made right, that it is more than acceptable for field hunting use out to and beyond 40 yards.
  Update: Tom Roster, working in conjunction with the Cooperative Nontoxic Shot Education Program (CONSEP) has put together a database on the performance of lead shot vs. steel shot. In this study is an X-ray analysis of over 16,000 ducks and geese.
  A fact revealed by this study: a steel pellet, with an energy level equivalent to that of a lead pellet, provides 5% to 10% deeper penetration.

 (3) Lead Effects