Pipe Size

Hi all,
The more I read about pipes and pipe smoking the more I see people talking about their pipes sizes and that some of them dedicate small ones or large ones for certain type of tobacco. I really would like some help in indicating the size range for these divisions. In other words, I would like to know what pipes are considered small, medium or large.

I tried to measure the chamber of my pipes and ended up with a range between 8.5cm3 to 15.5cm3 but that did not help me a lot since I couldn't find any online reference to know which range of sizes can be considered small and where does large pipes size starts.

Any help would be highly appreciated.

Thanks a lot for the information it was really helpful. First of all, I totally agree with tbradsim1 that without holding the actual pipe in your hand it is really hard to tell.
Regarding the video sent it was really great, using this I have now a base of reference. I checked the actual sizes of groups mentioned in the video online and deducted the following list of average chamber size:
Group 1: 7 cm3

Group 2: 8.5 cm3

Group 3: 9.5 cm3

Group 4: 10.5 cm3

Group 5: 12.5 cm3

Group 6: 13.5 cm3
According to the attached video group 4 is the most common which indicates that I can consider 10-11 cm3 as the avrage size and hence compare my pipes to it.
Thanks a lot again for the great help

For my pipes I used a small ruler to get the diameter of the chamber and used the poker of the pipe tamper to measure the internal height of the chamber. Multiplying the height by the radius (half diameter) square by 3.14 (pi) would give a very close chamber volume
V = h X pi X R X R
h: chamber height, R: half the chamber diameter, pi: 3.14
Moreover, I retrieved Dunhill pipes sizes (which unfortunately I have none of) from an online pipe shop called Alpascia (www.alpascia.com). In this website they give a lot of information about the pipes they offer which includes internal chamber height and diameter. That is how I was able to determine the average volume of different Dunhill pipes groups
Although this method will not give the exact chamber volume but it is the closest possible I thought of. I am not sure but it will be great if someone here will be able to give more precise method than this.

cortezattic thanks a lot, I will always check the forum, it is a great place to share ideas and benifit from your experiances.
acme I totally agree with you

Al you are right, the more I work on this the differences appear more. for Vauen (the brand most of my pipes are) it is around 12-13 cm3 which is a bit more like dunhil group 5 average. For big Ben it is almost the same but they have really large chambers for a relatively small pipes. they go up to 17 cm3 as a regular production and not an over size.
I think each factory have a certain number or sizes of drilling bits since most of the differences between pipes in the same brand are in length rather than diameter.
Cigarmaster thanks a lot, I am really glad to be a member of this forum. Regarding dunil sizes, the number I mentioned was the group average and it is very true that in every group there are several sizes and that was my first impression till I entered the number in excel file and retrieved the average. Moreover, if I had the chance I will always go to group 5 size since I think it is the best fit for me (I am not a small guy hehehe)
I am sorry to use the cm rather than inches but it is the most used in my area, in all cases I think it is so easy to convert them online