It seems to me that pumps and straight-pulls should be on the engineering table of every gun maker, and in fact, maybe they already are.

Both suffer from lack of force for primary extraction but in calibers like the .223 and even better, the more expertly designed {for automatic arms}, tapered 5.45x39 and 7.62x39 should be winners.

On that note, I'd love to see a straight-pull with a reversible bolt handle in 7.62x39 that takes AK mags.