I shall try to give some explanations concerning differences of Russian billiards (RB) from Pool. Beforehand I ask to excuse me for my bad English.
First, table. RB-table has the size of 12 foots, as a rule. There are also small tables 11 and 10 foots, but the basic, full is considered 12 foots. The size as a table for snooker.
Second, balls. Balls for Russian billiards is big. Diameter 68 mm and weight about 270-280 gramme (9.54-9.89 ounces).
Thirdly, pockets. Pockets at Russian table is small, little more than diameter of the ball. Corner about 72-73 mm, central about 82-83 mm.
It is possible to read in addition about Russian billiards here.
http://en.wikipedia.org/wiki/Russian_pyramid
Very much different cues for Pool and Russian billiards. Cues for RB more longer and thin than poolcue. Weight of RBcues from 650 up to 750 gramme (23-27 ounces), more often about 700 gramme (24.74 ounces). Length of RBcues from 1550-1700 mm (61 "-67 "), more often about 1590-1610 mm (62.9"-63.1"). Diameter of the handle at bamper from 25 up to 29 mm (0.99"-1.15"), more often about 26-27 mm (1.02"-1.06"), on a joint of 17-20 mm (0.67"-0.79"), more often about 18-19.5 mm (0.7"-0.77). Diameter of tip is 11-13 mm. Balance of Russian cue is 39-45 sm from bamper (15.3"-17.7").
The quotient of weight of Russian cue to weight of RB ball is about 2.4-2.7, as against a pool 2.9-3.3. There were heavier RBcues earlier, I made few times cues with weight 900 gramme, but it was very much extreme order, as a rule about 700 gramme. It is caused by human physiology. It is difficult for him to operate heavier cue to shot.
The length of RB cue is more because for its acceleration the greater distance is necessary. Therefore basic hand put further from cue-ball and for comfortable holding and moving cue the big length is necessary.
RB cue is thin, plays all its length as though it was one long shaft. It allows to make english easier with heavier balls . At moment of shot it is bent a little like letter "S" and transfers energy of acceleration to cue-ball. Except for that if RB cue would be thicker that comfortable balance would be difficult to make, is especial on heavy wood.
The most widespread design of RB cues is the butterfly design. Even it is a lot of butterflies. Sometimes on RB cues about 40 butterflies and even more are possible to count. But in my opinion the most optimum are 7-9 butterflies on the butt and 4-6 butterflies on the shaft. Application of such design makes RB cue more rigid and springy , and allows to play with heavy balls.
Here is picture of Russian billiards cue and Pool cue for comparison.
These are the general reasonings and very short explanations. If there are concrete questions, I shall try to answer.
Thanks.
Dmitry.