If Sen. Dianne Feinstein had to pick her political enemies, she couldn’t choose a better one than the Firearms Policy Coalition.

The gun rights group, which says its mission is “to protect and defend the Constitution of the United States and the People’s rights ... especially the inalienable, fundamental, and individual right to keep and bear arms,” is taking on the California senator and her long-running call for tougher regulations on firearms.

Feinstein “has one final goal before leaving office: a total ban on so-called ‘assault weapons’ and ‘high-capacity’ magazines,” the group said in a Thursday email calling on readers to “Stop Feinstein!”

In November, Feinstein joined a number of other Democratic senators in introducing the Assault Weapons Ban of 2017, which would ban the sale of more than 200 assault-type weapons and detachable magazines that hold more than 10 rounds of ammunition.

“After each (mass) shooting, we’re told it’s not the right time to act,” the senator said in a statement at the time. “We’re told to respect the victims by sitting on our hands. Well, the time for inaction is over.”

There’s little chance of the bill passing in this Congress. But you never know, so the gun rights group is asking recipients to “chip in a contribution of $25 today to help defeat Dianne Feinstein and her national ‘assault weapons’ ban!”

The group argues that there is no such thing as a civilian assault weapon. Without the guns Feinstein wants to outlaw, it says, “millions of Americans would be incapable of fully exercising their Second Amendment rights and protecting their loved ones. ... The firearms we currently own are constitutionally protected forms of self-defense, and many of them are at risk of prohibition or, maybe one day, confiscation.”

The Firearms Policy Coalition is based in Sacramento, so it’s no stranger to California politics. In recent weeks the group has come out against SB1177, which would extend the state’s ban on buying more than one handgun in a 30-day period to all firearms. The group says legislators “are determined to ration your guns.”

The group also opposes San Francisco state Sen. Scott Wiener’s SB221, which would ban gun shows at the Cow Palace. Its argument there is that “since gun stores are practically nonexistent in and around San Francisco, this bill would eliminate yet another alternative for lawful purchase and transfer of firearms.”

The problem for the Firearms Policy Coalition is that this is California, where Lt. Gov. Gavin Newsom could roll out an initiative for background checks for ammunition buyers in 2016 and see it approved with 63 percent of the vote. Far from hurting Newsom’s career, that initiative helped make him the odds-on favorite to be California’s next governor.

Feinstein could be forgiven for asking gun-rights groups if they could please attack her at least once a week from now until election day. California voters may have some concerns about Feinstein, but for most of them, a tough stance against military-style assault weapons isn’t one of them.

John Wildermuth is a San Francisco Chronicle staff writer. Email: jwildermuth@sfchronicle.com Twitter: @jfwildermuth