Pop opens are shockingly scary, but fortunately not harmful except for the spent case, one member got a nice burn on the forehead from the hot case.
H&R won't convert to ejectors, I don't think they even have all the ejector parts any more, specifically the ejector itself and the lift button for rimless chamberings, the underlug has to be machined and the ejector parts installed. Brownells used to carry the parts, but they've been out of the 30-06 size ejectors for a long time and the lift button is no longer even listed, but both can be made with a little work.
I would contact H&R and make arrangements to get it fixed, they'll have to replace the barrel, they don't shim, ask them to send or download a prepaid shipping label to cover shipping costs. I don't know if you have any recourse thru Dick's, but that may be worth pursuing too.
Tim
http://www.hr1871.com/support/repairs.asp