Reformed Baptist are not just Calvinistic in that they believe in the doctrines of Grace.
Reformed Baptists take the Second London Baptist Confession of Faith of 1689 and the 1677 Baptist Catechism as a sum of Biblical doctrine.
The are other Baptists who believe in predestination (mainly Hyper-Calvinists) but Reformed Baptists hold to Reformed veiws on other sudjects that set them different from other Calvinistic Baptists.
Christ spiritually present in Communion as opposed to just the memorial view.
Elder rule instead of Congregational rule
Accept historic church Creeds (i.e.. Apostles' , Nicene)
Since they are traditional Calvinists, and not Hyper-Calvinists, they support missionaries.
They believe in Covenant Theology as opposed to Dispensationism and New Covenant Theology.
Strict observance of the Sabbath or
LORD's Day, and a wariness toward "holidays"
Many practice the Regulatory Principle in worship.
The Liturgy of Reformed Baptists may seem quite different from other Baptists
The main group (founded in 1997) is the Association of Reformed Baptist Churches in America, but there are other groups that would be called "Reformed Baptist"
The Particular Baptists are the original "reformed" Baptists, originating in the late 1500's or early 1600's. This is the church tradition which ARBCA sought to revive in America when they founded their denomination.
http://www.pbpress.org/
Yet there do seem to be some churches today taking this name "particular" who are not holding to an
Orthodox Reformed Theology, but alter some of their doctrine and practices. (The Confederation of Particular Baptists I do not believe are neither Orthodox or historical in their practices and theology)
The Strict Baptists (mainly in England)
www.strictbaptisthistory.org.uk
In the Southern Baptist Convention there is a movement called the "Founder's Movement" which seeks to return to the orignal Reformed and Puritan doctrines of that church. This has led to many who call themselves Reformed or Historical Southern Baptists. There has actually been a lot of progress in their strivings.
www.founders.org
This may all be called "Reformed" Baptists, but other Clavinistic Baptist (like the Primitive Baptist) are not Reformed.