I will agree with the statement about lower manufacturing costs, and yes, that is part of the reason why it's not done more. Your statement about there possibly being more accuracy out of a chrome lined barrel than a non-lined one, is simply incorrect. I have to admit, that's the first time I've ever heard that, and I'm not sure what you base that on, honestly.
As a point of interest, low, mid, and high end rifle makers all sell and make barrels without chrome lining. I can't help but believe that if chrome lining was all some people make it out to be, more companies would be doing it. In most cases, it simply is an unnecessary addition to cost which will be passed on to the consumer.
Do I think chrome lining is a bad thing, absolutely not. Do I think it's a great thing? absolutely not. As with all things, there is a trade-off. In the case of chrome lining, the tradeoff for ease of cleaning and rust resistance is a decrease in accuracy. This is true in ALL barrels, not just high end accuracy jobs.
A good indicator of this, I think, is the fact that even the companies which chrome line their barrels don't on the DCM barrels. These are production barrels, too, not high end custom ultra accurate barrels.
We have seen both sides of this argument, and are one of the few companies who have. Keep in mind that we have in the past (and still do in some cases) offered chrome lined barrels. I personally have seen the evidence of chrome lined barrels being less accurate than non-lined barrels. You don't have to believe me, but it is what it is, and there's no arguing with cold, hard facts.
Is our decision to not chrome line our barrels a cost saving measure? I would be lying if I said no, but I will qualify that by saying it is not the primary reason. That reason is accuracy, period. We have built our line of rifles around accuracy, and this was just another way to achieve better results. The accuracy gain may or may not matter to some people, but we're happy with the choice we made, and have no plans to abandon it.
Jared (DPMS e-sales)