Ms. Feinstein, surrounded by victims of gun violence, congressional colleagues, and law enforcement officials, stood near pegboards with 10 guns attached as she admitted the difficulty in pursuing such legislation, even when harnessing the grief over the shooting of 20 schoolchildren in Newtown, Conn., last month.
“This is really an uphill road,” she said.
Since the expiration of a ban on assault weapons in 2004, lawmakers have shown a deep reluctance to revisit the issue. They cite a lack of evidence that the ban was effective and a fear of the gun lobby, which has made inroads at state and federal levels in increasing gun rights over the past decade.
Many lawmakers, including some Democrats, prefer more modest measures to curb gun violence, such as a bill that would enhance background checks of gun buyers or focus on enforcement of existing laws.
One such measure has been introduced by Sen. Patrick Leahy (D., Vt.), chairman of the Senate Judiciary Committee, who will start hearings next week on gun violence. His bill would give law enforcement officials more tools to investigate so-called straw purchasing of guns, in which an individual buys a firearm for someone who is barred from obtaining one on his own. Among the witnesses will be Wayne LaPierre, the executive vice president of the National Rifle Association.
“Sen. Feinstein has been trying to ban guns from law-abiding citizens for decades,” said Andrew Arulanandam, a spokesman for Mr. LaPierre. “It’s disappointing but not surprising that she is once again focused on curtailing the Constitution instead of prosecuting criminals or fixing our broken mental health system.”
More legislation is expected to arise soon. Sen. Kirsten Gillibrand (D., N.Y.) and Sen. Mark Kirk (R., Ill.) have agreed to work on gun-trafficking legislation; no federal law defines gun trafficking as a crime. Mr. Kirk is also working on a background-check proposal with Sen. Joe Manchin III, (D., W.Va.), a Democrat with a strong gun-rights record.
Joining Ms. Feinstein on Thursday were Rep. Carolyn McCarthy (D., N.Y.), who will introduce companion legislation in the House, and Sen. Richard Blumenthal (D., Conn.), who talked about the Newtown shooting.
“I will never forget the sight and the sounds of parents that day,” he said.
Several gun-violence victims, families of those killed, and others gave brief statements in favor of the bill.
The bill — which, unlike the 1994 assault weapons ban, of which Ms. Feinstein was a chief sponsor, would not expire after it is enacted — would ban certain characteristics of guns that make them more lethal and would require that grandfathered weapons be registered. More than 900 guns would be exempt for hunting and sporting.
Many Republican lawmakers, the NRA, and some Democrats oppose such a measure. “I don’t think you should have restrictions on clips,” Sen. Tom Coburn (R., Okla.) said. “The Second Amendment wasn’t written so you can go hunting; it was to create a force to balance a tyrannical force here.”
Backers of the ban say that the 1994 measure helped curb gun violence.
“The original bill, though flawed, had a definite impact on the number of these weapons faced by the police on streets and used in crimes,” said Adam Eisgrau, who helped write the ban. He said the new bill, with more explicit language on the types of features on banned weapons, “is far more respectful of firearms for recreation uses.”
Bans on assault weapons and high-capacity magazines were among the proposals made by President Obama and Vice President Joe Biden last week. Mr. Biden took the campaign for tougher gun laws to the Internet on Thursday in an online video chat as an effort by the White House to build public support.
List of firearms prohibited by name
Rifles: All AK types, including the following: AK, AK47, AK47S, AK–74, AKM, AKS, ARM, MAK90, MISR, NHM90, NHM91, Rock River Arms LAR–47, SA85, SA93, Vector Arms AK–47, VEPR, WASR–10, and WUM, IZHMASH Saiga AK, MAADI AK47 and ARM, Norinco 56S, 56S2, 84S, and 86S, Poly Technologies AK47 and AKS; All AR types, including the following: AR–10, AR–15, Armalite M15 22LR Carbine, Armalite M15–T, Barrett REC7, Beretta AR–70, Bushmaster ACR, Bushmaster Carbon 15, Bushmaster MOE series, Bushmaster XM15, Colt Match Target Rifles, DoubleStar AR rifles, DPMS Tactical Rifles, Heckler & Koch MR556, Olympic Arms, Remington R–15 rifles, Rock River Arms LAR–15, Sig Sauer SIG516 rifles, Smith & Wesson M&P15 Rifles, Stag Arms AR rifles, Sturm, Ruger & Co. SR556 rifles; Barrett M107A1; Barrett M82A1; Beretta CX4 Storm; Calico Liberty Series; CETME Sporter; Daewoo K–1, K–2, Max 1, Max 2, AR 100, and AR 110C; Fabrique Nationale/FN Herstal FAL, LAR, 22 FNC, 308 Match, L1A1 Sporter, PS90, SCAR, and FS2000; Feather Industries AT–9; Galil Model AR and Model ARM; Hi-Point Carbine; HK–91, HK–93, HK–94, HK–PSG–1 and HK USC; Kel-Tec Sub–2000, SU–16, and RFB; SIG AMT, SIG PE–57, Sig Sauer SG 550, and Sig Sauer SG 551; Springfield Armory SAR–48; Steyr AUG; Sturm, Ruger Mini-14 Tactical Rife M–14/20CF; All Thompson rifles, including the following: Thompson M1SB, Thompson T1100D, Thompson T150D, Thompson T1B, Thompson T1B100D, Thompson T1B50D, Thompson T1BSB, Thompson T1–C, Thompson T1D, Thompson T1SB, Thompson T5, Thompson T5100D, Thompson TM1, Thompson TM1C; UMAREX UZI Rifle; UZI Mini Carbine, UZI Model A Carbine, and UZI Model B Carbine; Valmet M62S, M71S, and M78; Vector Arms UZI Type; Weaver Arms Nighthawk; Wilkinson Arms Linda Carbine.
Pistols: All AK–47 types, including the following: Centurion 39 AK pistol, Draco AK–47 pistol, HCR AK–47 pistol, IO Inc. Hellpup AK–47 pistol, Krinkov pistol, Mini Draco AK–47 pistol, Yugo Krebs Krink pistol; All AR–15 types, including the following: American Spirit AR–15 pistol, Bushmaster Carbon 15 pistol, DoubleStar Corporation AR pistol, DPMS AR–15 pistol, Olympic Arms AR–15 pistol, Rock River Arms LAR 15 pistol; Calico Liberty pistols; DSA SA58 PKP FAL pistol; Encom MP–9 and MP–45; Heckler & Koch model SP-89 pistol; Intratec AB–10, TEC–22 Scorpion, TEC–9, and TEC–DC9; Kel-Tec PLR 16 pistol; The following MAC types: MAC–10, MAC–11; Masterpiece Arms MPA A930 Mini Pistol, MPA460 Pistol, MPA Tactical Pistol, and MPA Mini Tactical Pistol; Military Armament Corp. Ingram M–11, Velocity Arms VMAC; Sig Sauer P556 pistol; Sites Spectre; All Thompson types, including the following: Thompson TA510D, Thompson TA5; All UZI types, including: Micro-UZI.
Shotguns: Franchi LAW–12 and SPAS 12; All IZHMASH Saiga 12 types, including the following: IZHMASH Saiga 12, IZHMASH Saiga 12S, IZHMASH Saiga 12S EXP–01, IZHMASH Saiga 12K, IZHMASH Saiga 12K–030, IZHMASH Saiga 12K–040 Taktika; Streetsweeper; Striker 12.
Belt-fed semiautomatic firearms: All belt-fed semiautomatic firearms including TNW M2HB.