The results weren't all too surprising. The Brady Campaign had the oldest commenters with an average age of 55. The CSGV came in second with an average age of 52. The NRA came in 3rd with an average age of 46. And the VPC came in last with an average age of 41.
My conclusion is that even if you assume the average age of gun owners is increasing, there is a high chance they are younger than the average Brady Campaign and CSGV supporter and only slightly older than the average VPC supporter. If I were to increase the sample size, the results would probably move slightly more in favor of the NRA considering one of the youngest people in the sample was both a participant in the VPC's and CSGV's groups. Increasing the sample size would only decrease the weight that individual's age carries (unless there were more who participated in multiple anti-gun groups).
Another conclusion that can be made is that people who actively participate in the gun-debate are old in general. People my age (29) and younger had little to no representation in any of the groups. It appears the gun issue in general, whether pro or anti, is simply not a young person's concern with the anti side being even less of a young person's concern than the pro side.
So what does all this mean? It means the pro-gun side is going to continue winning. Out of all those who are passionate about the gun issue, we're among the youngest and greatest in number.
I just wanted an excuse to make a chart.