Yep, there's no safety issue with the bulging. I had to return mine, because I do reload and have 2 firearms in .45 colt and really disliked having to do so much working of the brass. If it will eject a higher power load and you don't intend to reload the brass, then if it shoots good, keep it. If you do start reloading, but reload only for that gun, you can use a Lee classic loader and as long as you only shoot them in that gun, you'll still be ok. It's only if you are sharing brass with a tight chambered firearm or if you shoot high power loads and it binds up that you should worry about it. There is a LOT of steel around the chamber of the .45 carbines.
I finally got an HY (2008) serial number model with a perfect chamber on the 3rd attempt. I just kept pestering the dealer/H&R until it was right. One thing to keep in mind is that if your dealer won't help you out on it, if you return it to H&R and it's outside their specification, they will probably offer to give you a different chambering, but not .45 colt. They are not making this barrel any longer and don't intend to I guess.
Good luck though and hope it works for you.