I don't own an SR9... yet, but the possibility is there. I haven't ever even seen any peening in person, but I know the fact of the matter is truth. Quite a few members here have posted about it. Some have posted pics of theirs. Some posting instances were they have dealt with Ruger about the situation were Ruger has replaced parts for free Because of the fact that it IS a known issue. After doing some searching here about it, most of the cases here appear to be within a few HUNDRED round it becomes an issue. Maybe others here can more accurately answer your question.
Don't get me wrong. The SR9 feels a MILLION times better in my hand than ANY Glock I have owned, therefor i really want to like this gun. That said, I just hope the peening issue is solved quickly and in a better way than: "we'll fix it when it happens" approach. I still haven't decided between the P95 or the SR9 for my next gun. The P95 seems to be a more affordable (time proven) design than the SR9. But the SR9 has a design/feel I would go for quicker. Right now i'm kinda playing wait and see till my next project (computer project)
If your not seeing it after 300 rounds it is very unlikely you will. If you see any peening it might get worse. But if it's not even started I doubt it will.With mine with the second barrel I had peening after working the slide about a dozen times.
From what I've seen, it can happen like rugerfreak's around 100, or like a few more around 300-400 rounds, but it can still show minor but noticeable peening around 800 or so rounds even. The 800ish round count is much rarer but I do recall seeing it sometime before on this forum, and I want to say a couple people started seeing it +1000 rounds too. But the average I'd have to say is between 300 and 400. Just examine the barrel and slide after each range trip and see what you can determine, if you think you have a peening problem, post pictures please, they greatly help us out in seeing whats going on.....in this case a picture IS worth a thousand words.
But peening itself isn't as often a problem as the forums and internet makes it out to be. I'm not saying it's not a real problem, just one that's been exaggerated by tons of extra posts about it. Most of which are honest questions about it, but if you did a search, you'd see quite a few threads about it, probably more referencing it in someway as a potential problem for a future purchase rather an actual post with pictures about one thats peening now.
Right now it's the biggest problem for the SR9, but it's still a slim chance you'll get one that will peen. If you get one that does, just know that it may take Ruger more than one or two trips to AZ to fix it, but they have been taking care of the ones that do peen.
I would think theoretically yes, but realistically no. The force of the slide and barrel hood slamming together is the direct cause of the peening in the first place. Cycling by hand shouldn't generate the force needed to deform the metal, I don't know what force you'd need to match it by hand, but I don't think you'd get too close. You'd think if the interference and timing is that bad to deform the barrel hood, it'd be difficult to cycle by hand. I can't tell you for sure as mine doesn't peen and is only a little shiny where the slide has rubbed it during my sessions with it.