Jacket skiving variations between different lots of Federal 9mm 147gr HST (P9HST2)

[QED]

Your penetration numbers seem low. I'm not saying they're wrong, but data from Doc and others have placed the 147gr and the 124gr +P well on the list of acceptable rounds, from 3" to 6" barrels (or so I have taken their data). The 124gr standard pressure has never made "the list" - the doctor has reported it is OK, but there are better options.

The penetration "numbers" are not my "numbers," they are from Federal, the manufacturer. Obviously, if HST bullet design in recent years has been modified so it expands less -- it will penetrate more, as is, undoubtedly, the case.

]I would expect deeper penetration after passing through 4LD if only for the same reasons you mention - less expansion, but I am truely surprised at the bare gel numbers you have posted. I hope you're wrong, as I carry both the 124gr standard pressure and the 147gr standard pressure in my G26.

The FBI protocol REQUIRES 12" penetration minimum in soft tissue/adequate simulant -- with and without any clothing barrier. Obviously, as Federal's own penetration "numbers" clearly show -- too much expansion, evidently in earlier HST "versions," results in under penetration and thus failure to meet FBI protocol penetration "numbers."

[rangerover]

From Federal's own data (probably several years old) in bare 10% gel:

9mm 124 gr. P9HST1 ---- 11.0" penetration
9mm 124 gr. +P P9HST3 ---- 10.0" penetration
9mm 147 gr. P9HST2 ---- 12.0" penetration

Thus my previous statement that the "older" and -- more expanded -- version of HST probably barely meets 12" penetration in gel is supported by Federal's own data.

Other "older" HSTs in other calibers also just barely made the 12.0" minimum penetration -- in gel. Good thing that Federal has evidently reduced expansion and thus increased penetration in "newer" versions of their HST JHP!

Please provide me with the link you are referencing. Thanks.

[QED]

Please provide me with the link you are referencing. Thanks.

Google "HST poster pdf"

[JBP55]

The revisions to the HST were possibly made so the HST would have slightly less expansion and slightly more penetration comparable to Gold Dot of the same weight. The old numbers on their website did not change when the ammunition changed.

[Moonshot]

I just read Doc's sticky from last year: 9mm 147gr duty load testing. I try to keep up on these things, but I must have missed this one. It answered my questions re: the new 147gr vs old 147gr HST. I apologize for wasting anyone's time with my recent posts. As usual, I should read more and type less.

[QED]

Those "older" HSTs that evidently expand too much and thus insufficiently penetrate are still just fine for target practice!

[DocGKR]

Several large LE agencies on the West Coast have been using 147 gr HST for over a decade with NO issues of failure to reach 12" of penetration in OIS incidents or lab testing, as noted in numerous previous posts...

[uechibear]

What contradicts the statement that a more expanded JHP (greater recovered frontal area) typically has reduced penetration? It's obvious that the "old" version has a significantly greater average recovered diameter than the "new" version of "same" HST. Have you not seen some tests in 10% "real" gel where some HSTs that were tested expanded too much and penetrated only about 10 inches? That's hardly up to FBI penetration standards which are -- 12" MINIMUM IN SOFT TISSUE!

...Obviously, if HST bullet design in recent years has been modified so it expands less -- it will penetrate more, as is, undoubtedly, the case.

When considering the reduced velocity of the newer ammo, as indicated here:

I chronoed some of the old 147gr and the new 147gr, and the velocities of the new lots of HSTs have dropped from 30-40fps.

... isn't it possible that they both penetrate to about the same depth, but the older ammo is actually better because of the greater diameter after expansion?

[QED]

When considering the reduced velocity of the newer ammo, as indicated here:



... isn't it possible that they both penetrate to about the same depth, but the older ammo is actually better because of the greater diameter after expansion?

30-40 fps difference in velocities is not a relevant factor in penetration difference between an "older" HST that has/had significantly larger frontal area and a "newer" HST that expands significantly less.

[QED]

As an additional FYI, the older style projectile expanded to .795" at its widest area whereas the newer style projectile expanded to .725 at its widest. That's a 9-10% difference in diameter.

I wonder what the penetration gains are with the newer projectile?

Even IF the "older" style with that expanded diameter was 180 grain @ 1000 fps -- it would penetrate only about 12.5" in "real" gel; only about 10.5" penetration is it for 147 grain in 9mm at same velocity. The "newer," and less expanded, HST just barely makes 12"!