A question for this group--

[jimmy the one]

80. fair points

krispos: .. most violent crimes don't involve guns so reducing the number of privately owned guns by 30% would only have dropped violent crime by 10% or so..

A fair point, only 8% in 2012. I should hereafter note that non fatal gun crime, rather than referring broadly to violent crime, declined during the periods noted, ~1992 - 2000, and ~2001 to 2017;

May 2013, Bur Justice Stats: Firearm-related homicides declined 39% and nonfatal firearm crimes declined 69% from 1993 to 2011
.. Firearm-related homicides dropped from 18,253 homicides in 1993 to 11,101 in 2011, and nonfatal firearm crimes dropped from 1.5 million victimizations in 1993 to 467,300 in 2011.
.. For both fatal and nonfatal firearm victimizations, the majority of the decline occurred during the 10-year period from 1993 to 2002. The number of firearm homicides declined from 1993 to 1999, rose through 2006 and then declined through 2011. Nonfatal firearm violence declined from 1993 through 2004 before fluctuating in the mid- to late 2000s.
.. In 2011, about 70% of all homicides and 8% of all nonfatal violent victimizations (rape, sexual assault, robbery and aggravated assault) were committed with a firearm, mainly a handgun. A handgun was used in about 7 in 10 firearm homicides and about 9 in 10 nonfatal firearm violent crimes in 2011. https://www.bjs.gov/content/pub/press/fv9311pr.cfm

2007-11, about 1% of victims violent crimes reported using a firearm to defend themselves.. A small number of property crime victims also used a firearm in self-defense—about 0.1 percent of all property victimizations.
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krispos: If a quarter of gun owners decided to get rid of their guns, where did they go?

They didn't go, national gunstock increases yearly due to sales, offset slightly by normal attrition failure due to age or unreliability factors (ring of fire, cheap sat night special discards). The reason for the decline in gun ownership rate 1992 to 2000 to now, largely, was that new gun owners did not keep pace with increases in population. From 1993 to 2001 US population increased by 25 million people. A goodly (maybe most) % of new guns during that period went to existing gun owners.

US pop -- 1993 260 million (rounded) ... 2001 285 million .... 2016 323.4 mill
1960 180.67 million .... 1970 205 million ...... 1980 227 million
http://www.multpl.com/united-states-population/table

And note your firearm sales graph somewhat corroborates a decline in gun ownershio rates 1993 - 2000, due a decline in gun sales from ~1993 to 2000, for handguns & rifles, while shotguns didn't budge much, remained flat. Read actual sales lines, not the linear line which is a mean or median or average indicator line to fit, ugh, whatever.
Rifles 1993 sales: 10 rifles/1,000 people; 2000: 6 rifles/1,000
Handgun 1993: 14 handguns/1,000; ............... 2000: 6 handguns/1,000
The increase in rifle & handgun sales began ~2009, the obama years (shotguns flat).
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Krispos: So twenty years later, the supply of new violent criminals dropped sharply as healthy, wanted babies grew into young adults and they were in better circumstances.

Fair points; I believe the rise in violent crime/gun crime from the mid 1960s to early 1990s was spurred by the rise in popularity of the semi automatic firearm (esp by criminals), primarily handguns, while revolvers dropped in relative proportion of national gunstock to ~19%, and semi auto handguns rose to ~19% (oddly enough same %, last figure I saw ~2010) - all rifles ~30%, shotguns ~30%, others the rest.

DoJ/BJS: During the two decades from 1973 to 1993, the types of handguns most frequently produced have changed. Most new handguns are pistols rather than revolvers. Pistol production grew from 28% of the handguns produced in 1973 to 80% in 1993.
The number of large caliber pistols produced annually increased substantially after 1986. Until the mid-1980's, most pistols produced were .22 and .25 caliber models. {tho criminals sought larger caliber sa handguns}.
Production of .38 caliber and 9 mm pistols began to increase substantially in 1987, so that by 1993 they became the most frequently produced pistols. http://www.bjs.gov/content/pub/pdf/GUIC.PDF

year ........... viol crime rate
1960 ...................... 161 ..
1966: ..................... 220 .. Semi-auto coming into vogue
1976: ..................... 468 .. Semi-auto en vogue
1980: ...................... 597 .. Semi-autos in full swing {wiki above}.
1986: ....................... 620 -- '87; 610 - '88; 637 - '89 {more large cal production}
1990: ...................... 732 -- 91, 758;
~1993: gun ownership rates begin to decline to year 2000
2013 ......................... 368 .. still TWICE the 1960's rate
https://www.democraticunderground.com/?com=view_post&forum=1172&pid=189985