are my plants root bound

hi guys first time grower got 4 plants about 4 weeks old they have been in 3g pots for about 2 weeks plants are between 7/8 inch long just looked under the pots and there are a few little roots coming out does this mean i have to transplant to bigger pots.dont really want to transplant agen but i want 2/3 ft plants. do you think i would have to get bigger pots to get plants that size. any helps great thanks

3 gallon pots should be sufficent for the full run unless you are looking to grow a canatree (which takes years) i have used as small as a 12'' pot and still yeilder 3 ozs a plant. the roots always seem to work their way out the bottom first its normal useually they will grow on the outside of the soil around the inner part of the pot and then gradually strengthen in the middle of the soil

thanks standox

nps duder goodluck