from: your article
"Duty ammunition meets or exceeds FBI standards. Hornady reports that when Critical Duty ammo is subjected to the FBI's intermediate barrier tests—auto glass, heavy clothing, plywood, drywall and sheet steel—you can expect at least 13 inches of penetration and expansion of between 1.2 and 1.6 times the bullet's original diameter."
I do not know whether the 1.5X diameter requirement, which you earlier contended did not exist, is stated as a minimum or as a goal.
Some increase in effective bullet diameter or area over caliber is generally required if the bullet is not going to over penetrate, meaning penetrate more than 18". Other than increase in bullet diameter or area necessary to limit penetration to not more than 18", my comment that there is no expansion requirement implied no specific number for expansion/deformation over caliber, such as 1.5x caliber.
In your thread about FBI handgun requirements you state that " ammunition submitted in response to FBI procurement solicitations for duty ammunition
must meet or exceed performance requirements of 12-18 inch penetration in the gel in each test and show uniform repeatable penetration,
and 1.5 times caliber expansion, and high bullet weight retention."
The above seems like an expansion requirement that is not met in the tests for auto glass and sheet steel from Hornady's own tests (although 12-18" penetration is).
Here's another test of the Critical Duty through auto glass by "DocGKR": Penetration: 15.5", Recovered diameter: 0.48"(1.35x caliber).
Critical Duty rounds do not show repeatable increase of bullet diameter (expansion/deformation) of 1.5X caliber in auto glass or sheet steel protocols tests --
if that, indeed, is the FBI requirement for expansion/deformation as suggested by your quoted statement. However, if the requirement is 12-18" penetration in gel with whatever expanded/deformed diameter, Critical Duty seems to pass that test reasonably reliably.
And as previously mentioned,
if the requirement for expansion is 1.5xcaliber, then that limits penetration to about 15" -- instead of 18" set previously as maximum acceptable penetration.
The round was accepted for duty by the FBI.
There is no doubt about that; it's public information.
That is consistent with their claim.
Yes, they accepted the round even though Hornady's own tests, as well as other professional tests, show that Critical Duty does not expand to at least 1.5xcaliber after penetrating through auto glass and sheet steel protocols barriers. That certainly raises a question of whether 1.5x caliber expansion is a requirement that must be met with all protocols tests.
And one more time, that is expansion.
In a broad sense any deformation can be referred to as expansion (increase in size), however, my point was that when referring to JHPs specifically, expansion (or mushrooming) is caused by stagnation pressure which generally requires a JHP cavity that is not closed -- unlike when JHPs penetrate through sheet steel and auto glass. An example that I have previously given was that a FMJ can deform after impact with some barrier resulting in increase in the bullet frontal area, but such deformation would not ordinarily be referred to as "expansion" but deformation. And, of course, unless a JHP "mushrooms" it is generally not likely to increase its average recovered diameter to 1.5x caliber -- the stated or implied FBI requirement in your above quoted statement.
cannot tell whether you are being deliberately obtuse for the sake of arguing, or if you just cannot comprehend English.
Actually, I am interested in technical, factual discussions