GLENDALE (CBSLA.com)— Are the weapons that were used in the Conn. school shooting sold in Southern California?

Investigators believe Adam Lanza, 20, mostly used a Bushmaster .223 assault rifle to kill 26 people, including 20 children, at Sandy Hook Elementary School in Newtown on Friday.

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Sources said Lanza also had three other guns with him.

CBS2’s David Goldstein said he had no problem finding a Glock 10mm handgun or a Sig Sauer, both similar to firearms Lanza reportedly had in his possession, at the Gun Gallery in Glendale.

Goldstein also found a weapon similar to the Bushmaster AR-15, except the magazine only held 10 rounds and couldn’t be reloaded rapidly.

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Retired ATF agent Jay Wachtel said the California version of the Bushmaster is limited to 10 rounds, instead of 15 or 30, because of the state’s assault weapon ban.

However, he said that doesn’t really matter when it comes to killing.

“The problem with the Bushmaster or any (similar) rifle is the lethality. The kind of ammunition it uses. The speed of those projectiles is simply devastating,” Wachtel said.

Wachtel said gun control is difficult with so many weapons on the streets.

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“There’s really no realistic opportunity at gun control, it’s more an illusion,” he said.