The Rugged Surge has interchangeable end caps, which changes the exit hole diameter.
I bought it with the 30 cal end cap and I’ve never changed it.
I shoot 223 up to 308 and haven’t had any issues.
Is the sound that much different? I don’t know, I’m half deaf. Ask my wife!
Samesies. I bought smaller end caps and got lazy. I don't even change out the end caps anymore. Correct/smaller size end caps may reduce the sound signature by 1 to 2 dB, but not enough for me to bother with changing the end caps anymore.
One thing to be aware of with Rugged is that the end cap(s) are not crowned to the end/diameter of the suppressor tube. Meaning, if you manage to drop the can, Murphy's law says it will hit the concrete on the muzzle/exit end, distorting/damaging the end of the suppressor tube. Then, you'll have to send it back to Rugged for repair/replacement of the suppressor tube.
AMHIK. I went through that and Rugged were very good and very quick to effect the "repair". But, it should not have been necessary in the first place. I really do like Rugged, but to me, that is a very simple problem to solve. They expressed zero interest in doing so, so I'm conflicted as to whether or not I'll buy another Rugged suppressor again.
All they would have to do is to make a very minor change in their end caps so that the end cap covers/protects the entire outer diameter of the tube. That way, if the can gets dropped, the cap takes the hit, not the tube. And, if the cap gets dinged, it can still be removed and/or replaced by the user/owner. That, as opposed to having to send the whole can (with a copy of the ATF paperwork) back to Rugged.
Hell, if they made that one improvement, I'd buy/pay for the new end caps and they'd have a damned near perfect product.