HomeLatest ThreadsGreatest ThreadsForums & GroupsMy SubscriptionsMy Posts
DU Home » Latest Threads » Forums & Groups » Topics » Justice & Public Safety » Gun Control & RKBA (Group) » But guns are special » Reply #109
In the discussion thread: But guns are special [View all]

Response to jimmy the one (Reply #96)

Wed May 27, 2015, 07:44 PM

109. I thought we were discussing centerfires, but since you mention it...

"Gun owners don't use 22 rimfires for home defense? "

I thought it was a given that we are discussing centerfires, but rimfires are a good topic to bring up. And yes, 40gr and 55gr .223 JHP penetrate less than or equal to typical .22LR in both drywall and gelatin.

The reason is that .22LR are going way too slowly, and spinning way too slowly, to disintegrate on impact with a soft barrier, whereas lightweight .223 JHP traveling nearly 3000 ft/sec and spinning at 240,000+ rpm tends to disintegrate in gelatin or after getting whacked by a couple sheets of drywall. As a result, .22LR gelatin penetration is typically 9" to 18" in gelatin depending on load, whereas 40gr .223 JHP may penetrate 7" or less, and a 55gr .223 JHP typically penetrates 10" to 12".

There are plenty of good reasons to prefer a centerfire over a rimfire (reliability being #1, and effectiveness #2), but a rimfire is nothing to sneeze at, especially in terms of penetration.

"The .223 has about 10 times more kinetic energy than a 22 short or long (by plurality used most to commit suicide). Not possible the .223 is less hazard. "

Your error is in assuming that kinetic energy correlates with drywall and gelatin penetration. It does not; in fact, all else being equal, it tends to be inversely correlated once you reach the fragmentation threshold. What matters more is fragmentation, and lightweight .223 readily fragments whereas .22LR does not.

For example, here's three gel tests of a 50gr .223, one out of an 11.5" barrel, one a 14.5", and one a 19.5". The longer the barrel and the higher the kinetic energy, the less the round penetrated.



For an even clearer example, compare a 40gr at 1250 ft/sec (.22LR) to a 40gr at 2750 ft/sec (.22 Hornet). More-than-double the velocity and quintuple the energy, and penetration goes down, but temporary cavity *diameter* goes up.





Double the energy *again* (to twice that of a .223, by shooting a 55gr load out of a .30-06 deer rifle), and you still get less penetration than a 40gr .22LR...but horrific "tissue" damage:



FWIW, I spent a couple hours looking, and the only .22LR load I found that penetrates less than a 40gr .223 JHP are some prefragmented .22LR made for squirrel hunting (Quik-Shok, and CCI Segmented HP), and those would likely penetrate drywall like any other .22LR HP. Typical .22LR hollowpoints will penetrate as much as or slightly more than 55gr .223 JHP.

Now, in terms of damage to the target, there is no question; .223 and .357 (and buckshot, and .30-06...) create a *wider* wound than .22LR, by a large margin, and .223 *FMJ* will penetrate more than most .22LR. But comparing .22LR defensive HP (CCI Velocitor is widely regarded as the best) to good .223 defensive JHP, penetration is comparable across the board.

"An ar15 - 0.223 fmj carries 3 times more kinetic energy at close range than a 357 magnum, 4 times more than a 9mm. You are contending the .223 is somehow 'less hazard' to bystanders & neighbors, than those?"

.223 JHP penetrates less than 9mm and .357 JHP. .223 FMJ penetrates less than 9mm and .357 FMJ. Comparing apples to apples, then yes, .223 is a safer choice than either, which is a primary reason why law enforcement SWAT teams have replaced 9mm submachineguns with non-automatic .223 carbines.

"Dare: I will stand behind a drywall & paneling & be shot at by a 22 rimfire, you stand behind it & get shot at by an ar15. "

If you were standing behind the third "wall" in this test, which would you rather be shot at with? The .223 loads that didn't penetrate the third wall, or the 9mm/.380/00 buckshot loads that did?

.223 with appropriate load choice is less likely to overpenetrate than any other effective load. The few loads that manage to penetrate less than good .223 JHP are those specialized for shooting squirrels and birds, and none of those are particularly effective at incapacitation even if they ultimately prove lethal.

Reply to this post

Back to OP Alert abuse Link to post in-thread

Always highlight: 10 newest replies | Replies posted after I mark a forum
Replies to this discussion thread
Arrow 112 replies Author Time Post
discntnt_irny_srcsm Apr 2015 OP
Human101948 Apr 2015 #1
discntnt_irny_srcsm Apr 2015 #2
Human101948 Apr 2015 #3
discntnt_irny_srcsm Apr 2015 #6
Human101948 Apr 2015 #15
discntnt_irny_srcsm Apr 2015 #18
pablo_marmol Apr 2015 #44
discntnt_irny_srcsm Apr 2015 #48
Human101948 Apr 2015 #4
discntnt_irny_srcsm Apr 2015 #7
Human101948 Apr 2015 #13
discntnt_irny_srcsm Apr 2015 #14
Human101948 Apr 2015 #21
discntnt_irny_srcsm Apr 2015 #22
Eleanors38 Apr 2015 #8
Human101948 Apr 2015 #12
Eleanors38 Apr 2015 #23
gejohnston Apr 2015 #26
Human101948 Apr 2015 #35
gejohnston Apr 2015 #37
GGJohn Apr 2015 #32
Lizzie Poppet May 2015 #92
beevul Apr 2015 #50
Lizzie Poppet May 2015 #91
spin May 2015 #94
ileus Apr 2015 #5
discntnt_irny_srcsm Apr 2015 #9
Shamash Apr 2015 #10
discntnt_irny_srcsm Apr 2015 #11
Human101948 Apr 2015 #16
discntnt_irny_srcsm Apr 2015 #17
beevul Apr 2015 #51
Eleanors38 Apr 2015 #24
discntnt_irny_srcsm Apr 2015 #69
Eleanors38 Apr 2015 #77
Puha Ekapi Apr 2015 #40
Human101948 Apr 2015 #19
discntnt_irny_srcsm Apr 2015 #20
Eleanors38 Apr 2015 #25
Human101948 Apr 2015 #36
Eleanors38 Apr 2015 #46
Human101948 Apr 2015 #49
friendly_iconoclast Apr 2015 #52
Human101948 Apr 2015 #53
friendly_iconoclast Apr 2015 #54
Human101948 Apr 2015 #58
spin May 2015 #95
Human101948 Apr 2015 #64
discntnt_irny_srcsm Apr 2015 #66
Human101948 Apr 2015 #67
discntnt_irny_srcsm Apr 2015 #68
Human101948 Apr 2015 #70
DonP Apr 2015 #71
discntnt_irny_srcsm Apr 2015 #72
Human101948 Apr 2015 #73
discntnt_irny_srcsm Apr 2015 #74
Starboard Tack Apr 2015 #29
ileus Apr 2015 #31
Starboard Tack Apr 2015 #33
gejohnston Apr 2015 #34
Starboard Tack Apr 2015 #38
gejohnston Apr 2015 #39
ileus Apr 2015 #43
ileus Apr 2015 #42
Eleanors38 Apr 2015 #47
Starboard Tack Apr 2015 #55
Eleanors38 Apr 2015 #57
Starboard Tack Apr 2015 #60
Eleanors38 Apr 2015 #61
Starboard Tack Apr 2015 #62
ileus Apr 2015 #41
Starboard Tack Apr 2015 #56
upaloopa Apr 2015 #27
discntnt_irny_srcsm Apr 2015 #28
ileus Apr 2015 #30
benEzra Apr 2015 #45
jimmy the one Apr 2015 #59
benEzra Apr 2015 #75
jimmy the one May 2015 #85
blueridge3210 May 2015 #86
benEzra May 2015 #87
friendly_iconoclast May 2015 #89
blueridge3210 May 2015 #90
benEzra May 2015 #88
jimmy the one May 2015 #96
blueridge3210 May 2015 #97
discntnt_irny_srcsm May 2015 #98
blueridge3210 May 2015 #99
discntnt_irny_srcsm May 2015 #100
Duckhunter935 May 2015 #106
LineLineLineLineLineLineLineNew Reply I thought we were discussing centerfires, but since you mention it...
benEzra May 2015 #109
jimmy the one May 2015 #110
benEzra May 2015 #111
blueridge3210 Apr 2015 #76
ManiacJoe Apr 2015 #78
benEzra May 2015 #79
Straw Man May 2015 #80
benEzra May 2015 #81
discntnt_irny_srcsm May 2015 #82
benEzra May 2015 #83
DonP May 2015 #84
Matrosov May 2015 #102
petronius Apr 2015 #63
discntnt_irny_srcsm Apr 2015 #65
pablo_marmol May 2015 #93
Matrosov May 2015 #101
gejohnston May 2015 #103
Shamash May 2015 #104
beevul May 2015 #105
pablo_marmol May 2015 #107
friendly_iconoclast May 2015 #108
pablo_marmol May 2015 #112
Please login to view edit histories.