I am sorry I am late to this dance. I do have a lot of 1911 experience (not so much Ruger tbh).
What you are describing is *probably* a classic magazine issue. It's not the gun at all most likely. It's like swc rounds in a hybrid feed lip magazine. Does just what you are describing. If you aren't familiar with 1911 magazine feed lip designs and issues, google that and read up.
Two sources of the issue are spring rate but more likely feed lips. Feed lips and bullet/projectile selection are critical here. I should also mention OAL as it matters. As a caveat, I've tuned 45, 9mm, and 40 s&w with the same issues to work, but not .38 Super (would love to do so, though!). But it's the same issue.
Ramped barrels are a big headache as they require tuning the cartridges' meplat length to replicate the projectile meplat length they were designed for. It's not a clearly intuitive process. I built some guns with Clark barrels and they helped me work through this, as did Herb Germaine, a noted past 1911 builder, who was then local to me and a friend.
First question is what magazines are you using, what bullets, and what OAL are they loaded to?
There was an amateur gunsmith who made a great blog post about this issue. I am also certain I bookmarked it but right now can't lay eyes on it. I'll try to find it tomorrow night when I have time again.