Replacement ramrods would be easier to make for the larger calibers, and less likely to break in the first place.Going strictly from memory, most references to calibers in the 1700s ran around 48 to 53 caliber. Usually expressed as X number of balls to the pound of lead. No doubt some small caliber small game rifles were made but I think they would be unusual. Assuming most people would have only one rifle, a circa 50 caliber would be more useful for hunting and protection.
As more responses come in, I'm curious to see if my vague impressions hold up.