jdoe, i think bigcock&titluvr was talking about the "second" (sometimes called "third" sphincter")
Ok everyone, time for a quick anatomy lesson.
Ok so as we all know there is the external sphincter (you have some voluntary control over this one) and then about an inch and a half (give or take) inside is the involuntary sphincter (sometimes called the second sphincter which gets confusing as I am about to explain)
So then you have the rectum which is anywhere from 10-15 cm in length (just under 4 to just under 6 inches). Again this is on average. It is not out of bounds of reason to think that some people may have longer. Hence the 7 to 8 inches some people are reporting before they experience discomfort/pain. Or a louielouie82 said; it feels like it hits a wall. For him he said it was around 7 1/2. Side note to this, I have no idea if these people had measure their partners, and also if someone has a really beefy ass, there may be no way to get one's entire dick in, the cheeks will stop you, so maybe people did measure their guys, but neglected to account for this. I dont know.
Anyways...at this point, some (for arguments sake) lets say 4 to 8 inches in a person is going to encounter what is commonly called the "second" sphincter (or sometimes "third" if you counted the two at the beginning separately) Perhaps second involuntary sphincter would be more accurate
except it wouldn't. What you are hitting is technically not a sphincter at all, but a band of muscle that acts similar to one.
This is the puborectalis (sometimes called the pubo-rectal sling). It's a band of muscle that wraps around the colon, forming a boundary between the rectum and the sigmoid colon. This muscle is responsible for holding feces back until it is ready to drop into the rectum, where it is stored briefly before being voided. Since it acts very much like what we think a sphincter should act like, that is where the confusion comes in. This is further exacerbated by the fact that it is sometimes called the Sphincter of O'Beirne.
Since this muscle is involuntary, the same rules of penetrating it apply as when one is penetrating the true sphincters. It needs to be relaxed, teased and gently dilated. This is why petite has success when she uses toys that are at least as long as the BF. You notice they don't have to be as thick. This will get the PR muscle to slowly relax and be more accepting of a cock (for those of you who like to finger first to prepare, think of it like in those terms)
Sooooo, going through the PR muscle would have a similar sensation as of gong through a "second" hole.
Hope this helps. Dang that was a lot of info I just gave. I think I will copy it and start a thread of my own with it in there, to reference people to.:biggrin1:
