When rank-and-file lawmakers emerged from closed-door meetings at the Capitol on Monday, many weren’t entirely happy with the post-Newtown gun control legislation package they’d hammered out.

That’s the nature of a bipartisan bill — no one ever gets everything they want.

But one thing is certain — those same rank-and-file lawmakers said their proposal was the “most comprehensive” package of gun control legislation in the country.

“In Connecticut, we’ve broken the mold,” Sen. President Donald Williams said Monday at a press conference. “We just put together Democrats and Republicans in a bipartisan process on one of the most divisive issues in the United States.”

Senate Minority Leader John McKinney, R-Fairfield, said some lawmakers were still making up their minds on the bill, but there was “no doubt” the legislation would pass both chambers on Wednesday. McKinney said there was strong support among Senate Republicans.

“I think we may be around 50 percent of our caucus,” he said.

Legislative leaders declined to say which side compromised on certain provisions during negotiations, but they all agreed they would be discouraging individual lawmakers from calling amendments during debate on the bill Wednesday.

House Speaker Brendan Sharkey also said that this would be the last piece of gun-related legislation raised in this session. He said they may take up more mental health or school security issues this year, but debate over gun issues will end Wednesday.

Under Connecticut’s legislation, House Minority Leader Lawrence Cafero, R-Norwalk said no one will lose their right to own a gun. However, going forward in order to purchase a firearm an individual will need a certificate and will need to pass a background check if they want to purchase ammunition. The bill adds about 100 more weapons to Connecticut’s assault weapons ban, which currently includes 66 models.

The legislation also bans the sale of high-capacity ammunition magazines. The legislation allows residents who already own the magazines to keep them, so long as they register them with the State Police by Jan. 1, 2014. Under the bill, possession of an unregistered high-capacity magazine will be considered a Class D felony.

Click here to read the draft outline of the gun and mental health provisions and here for the school security portion of the bill

“If you value bipartisanship, I believe it’s the best possible bipartisan bill that you could get done,” Rep. Gary Holder-Winfield, D-New Haven, said of the draft legislation lawmakers reviewed Monday afternoon.

Rep. Peter Tercyak, D-New Britain, agreed.

“I think we generally have faith that this is the best deal that we’re going to be able to get if we’re going to pass something that’s bipartisan,” he said.

The prospective nature of the high-capacity magazine ban will come as a disappointment to families of Newtown victims who lobbied lawmakers Monday as they ducked into their respective caucuses.

Tercyak said he would have liked the bill to be “more assertive” in banning magazines that people already own. But he said he could live with the compromise of requiring people to register their magazines.

“Considering where so very many people started, this is a satisfying place to end up,” Tercyak said.

Holder-Winfield said he did not believe there will be any change in the prospective nature of the high-capacity magazine ban. Given that the bill is the product of negotiations between all four of the legislative caucuses, he said the legislation had to be written that way.

“I think with the process we had, a full ban might blow up the deal,” he said.

The high-capacity magazine ban also prohibits gun owners and sportsmen from carrying a magazine with more than 10 bullets outside their home or outside a shooting range. Newtown families told lawmakers it would be a difficult law to enforce.

“If you don’t declare it then you can’t own it,” said Rep. Ed Vargas, D-Hartford, explaining how law enforcement would deal with it.

The bill also increases the penalties for many firearm trafficking and illegal possession offenses and requires individuals who want to purchase a rifle to be 21 years old. It expands the “lookback” period for individuals who have been involuntarily confined or voluntarily admitted to a hospital for psychiatric disabilities.

The proposal already has some gun advocacy groups crying foul.

“It is ludicrous to expect people that have firearms capable of holding 15 rounds to only load 10 rounds inside of them,” Scott Wilson, president of the Connecticut Citizens Defense League, said. “Do criminals really care about these laws?”

Holder-Winfield said he felt a number of proposals in the bill will help to reduce gun violence, including registration of all firearms and tougher penalties for trafficking weapons. Handgun deaths are more common in urban areas than deaths attributed to semi-automatic rifles like the one used by the gunman at Sandy Hook.

“I think those types of things are significant, and it’s understandable that people are upset about the fact that we don’t . . . deal with a full magazine ban,” Holder-Winfield said. “But when you look at those things, we have done something significant.”

Tercyak said the bill contains mental health provisions that would limit someone’s ability to acquire a gun if they have a history of psychiatric hospitalization.

“While many of us are not happy with everything there, there is a general consensus that we can live with it,” he said.

Tercyak said he thinks there may be an effort later in the legislative session to pass bills that make more changes to the state’s mental health system. Lawmakers had concerns about the ability of the state to pay for mental health provisions, he said.

“The budget’s still very fluid now, but there’s a commitment to have funding for what we’re proposing, that this won’t be separate from our final budget” he said.

Rep. Toni Walker, D-New Haven, said at the moment there’s no fiscal note attached to the bill even though the policies outlined indicate there’s a need for one.

“We are going to have to have a very long conversation about how this works into the budget,” Walker, who co-chairs the Appropriations Committee, said.

Rep. Stephen Dargan, D-West Haven, who chairs the Public Safety Committee, said the legislation calls for long guns to be permitted and ammunition registered with the state, which will require more staff to do background checks.

“I think we need to talk about how much it will cost the state to implement and put forward,” Dargan said.

He estimated the number of people that the Department of Emergency Services and Public Protection would need to hire would be between 16 to 18.

“There’s going to be a lot of money involved,” Dargan said.

The proposal also includes measures to improve school security and mental health care in the state.

It creates a task force to study Connecticut’s mental health system with a special focus on the 16- to 25-year-old population. The gunman in the incident was 20 years old and, according to various reports, suffered from some form of mental or emotional disorder. The bill also looks to expand coordinated support systems for those involved with the Probate Court system.

The outline of the bill also asks the state Insurance Department to evaluate and report on its method for determining compliance with state and federal mental health parity laws. It also contains several changes related to the Program Review and Investigations Committee report on commercial insurance, which often doesn’t cover many of the behavioral health or mental health treatment covered by public insurance like Medicaid.

The bill also expands the membership of the Board of Firearm Permit Examiners to seven to include a mental health professional and a retired Superior Court Judge.