I know that Hornady states that it can potentially cause the gas system to function as if its over-gassed.  Yet I still hear a few good reports from guys using it in carbines or mids.  I guess before I plunk down $20 to try some I just want to test the waters here and see who's shot them and how they worked out.

Edit:  Go ahead and feel free to post up if you're shooting it in a carbine.  This is non-exclusive.

I've shot it out of my carbine.  I've had no ill effects, at least not that I can tell.  I probably have a 150 - 200 rounds down it.  I guess I actually forgot about this, not that it would have stopped me.  

Here is another question.....I realize that it is hot, and loaded to a higher pressure correct?  What then, could it possibly do to your gun?  Meaning, my guns (as are most of ours), are 5.56 chambers, which is usually a couple of hundred feet a second faster than .223 ammo.  and at 5 or 6  thousand psi more stout.  Can this ammo be that much more hotter?  

I hope somebody smarter than me wil chime in, and shed some light here.  L2

Ya I figured that as long as the gun is truly 5.56, its probably not anything to worry about... but I have no REAL idea.

Soooooo, in other words, it may be extracting hot burnig powder, still in progress?  If so, that may explain why I have no eyebrows left.  L2

^^^^^ What he said. ^^^^^  I use them for groundhogs 53gr  in my RRA 16 mid. I've ripped the lip off of a few cases but a gentle push with a cleaning rod usely knocks it out. What bothers me is it ruins the next bullet up by jamming the bullet back into the cases



Edit : I have a target on here somewhere with them think it was a ten round group
I don't know how or have the ability to look up my old posts.

The Superformance rounds have the same peak pressure as any other 5.56 round.....it just lasts longer.  In my midlength SASS all the primers blow out.  The only way i can shoot them is with SLASH's heavy buffer and spring.  An adjustable gas block would fix any problems also.

Makes perfect sense Sir.    Maybe I have been lucky???  I have not had any blown primers, ripped cases, or flames.  I run a carbine, with a Spikes h3 buffer.  But that was anyway, anyhow.  I shoot the 53 gr. V-max, and the 75 gr. HP.  I was only kidding about the eyebrows.  I shave those off.  L2

I tried them, ran fine but they were getting extracted early (bent rims/extractor marks) and it was running the gun(s) too hard. On top of all that the accuracy was terrible (308 included) so I stopped buying it.
 

Thanks for the responses.  So I guess I can feel safe trying it out.  My gun runs fairly "soft" already, so it may work out OK.  If not, does anybody know of any vmax or varmint tipped ammo loaded to 5.56 NATO pressure instead of 223 SAAMI?  I imagine that would produce velocities pretty similar to superformance and aid function, instead of impede it.