Admittedly I have only 5 books dealing with Confederate cap & ball revolvers but I have yet to read of a .44 caliber brass framed Confederate "copy of a Colt 1851".
The Dance Brothers pistols were not really copies of the Colt 1851 but except for the missing recoil shield the .36 caliber Dance was close.
The .44 caliber Dance was more of a copy of the .44 Colt Dragoon which includes its much larger size.
Not all Dance Brothers revolvers were without the recoil shield but most were.
They all were iron framed guns.
William A. Gary's Confederate Pistols (Taylor Publishing Company, Dallas, Texas, 1986), speaking of the Dance Brothers revolvers on page 63 says,
"The Dance Brothers were the fourth largest producers of handguns in the Confederacy and the only firm to produce both .44-caliber and .36 caliber revolvers."
While on the subject of Confederate copies of the Colt 1851 Navy, not all of them had brass frames and not all of them had round barrels.