I picked up one of the new Ruger BX-25x2 magazines for the Ruger 10/22 last week and thought I'd take a few minutes to share my impressions of it, along with a few photos.
HISTORY
For nearly as long as extended-capacity detachable magazine rifles have been available, GIs and other fast-action shooters realized they could decrease the time needed to reload their weapon and get back into action more quickly by taping/clipping two detachable rifle magazines together. High-speed recreational .22 shooters quickly embraced this concept as a way to keep those beverage cans bouncing or spinning targets spinning with minimal interruptions. This has led to a huge secondary market segment for high-capacity rimfire rifle magazines, including those that can be snapped together to make a double-capacity-mag, for many popular .22 carbines such as Ruger's 10/22. Ruger finally claimed a chunk of this extended-capacity-mag market with the introduction of their popular BX-25 25-shot magazine, and is now going after the dual/clipped-together mag market with their newest offering, the BX-25x2 double mag.
INITIAL IMPRESSIONS, STATS
First, despite what the printing on the left edge of the package indicates, this is NOT "two coupled 25-round magazines"; you cannot pop this magazine apart and have two separate 25-shot mags, and for that reason, I think the package statement is a bit misleading. It is, in fact, a single mag that feeds from separate feed tracks/lips located at opposite ends of the mag, so perhaps "permanently coupled dual magazine" would be a more accurate description. Even so, the mag does seem to share many parts with the standard BX-25 mag, but its main selling point is the compact central portion of the main body, which reduces the width of the mag by about 20% compared to some competing twin-coupled-mag designs (or even taped-together stock BX-25 mags).
Overall length of the BX-25x2 is about 9.25 inches (tip-to-tip), compared to 7.625" (seven and five-eighths inches) for a standard BX-25. Side-to-side thickness is about 2 inches, vs. 1.25 inches for a single BX-25 mag. Front-to-back measurements for either style of mag are about the same, if measured at the same point on the mag bodies.
BX-25x2 on the left, BX-25 on the right:
A quick measurement of a popular competitor's dual-magazine design showed a clipped-together width of about 2.5 inches, so the Ruger BX-25x2's decrease in this dimension is an appreciable and quantifiable 20%. Whether or not it makes any practical difference in actual use will be up to the user. Carrying either type of mag (Ruger's BX-25x2 dual-built-mag design, or two single-mags-clipped-together competitors' mags) on your belt, for instance, will still require a rectangular pouch approximately the size of a standard masonry brick; a curved/contoured pouch could be made slightly smaller and still work, but it's still going to be pretty chunky. Pouch flaps/lids must fit snugly and close securely to prevent the smooth, curved mags of either type from working their way out of a pouch through a gap and becoming lost during movement.
(to be continued...)

HISTORY
For nearly as long as extended-capacity detachable magazine rifles have been available, GIs and other fast-action shooters realized they could decrease the time needed to reload their weapon and get back into action more quickly by taping/clipping two detachable rifle magazines together. High-speed recreational .22 shooters quickly embraced this concept as a way to keep those beverage cans bouncing or spinning targets spinning with minimal interruptions. This has led to a huge secondary market segment for high-capacity rimfire rifle magazines, including those that can be snapped together to make a double-capacity-mag, for many popular .22 carbines such as Ruger's 10/22. Ruger finally claimed a chunk of this extended-capacity-mag market with the introduction of their popular BX-25 25-shot magazine, and is now going after the dual/clipped-together mag market with their newest offering, the BX-25x2 double mag.
INITIAL IMPRESSIONS, STATS
First, despite what the printing on the left edge of the package indicates, this is NOT "two coupled 25-round magazines"; you cannot pop this magazine apart and have two separate 25-shot mags, and for that reason, I think the package statement is a bit misleading. It is, in fact, a single mag that feeds from separate feed tracks/lips located at opposite ends of the mag, so perhaps "permanently coupled dual magazine" would be a more accurate description. Even so, the mag does seem to share many parts with the standard BX-25 mag, but its main selling point is the compact central portion of the main body, which reduces the width of the mag by about 20% compared to some competing twin-coupled-mag designs (or even taped-together stock BX-25 mags).
Overall length of the BX-25x2 is about 9.25 inches (tip-to-tip), compared to 7.625" (seven and five-eighths inches) for a standard BX-25. Side-to-side thickness is about 2 inches, vs. 1.25 inches for a single BX-25 mag. Front-to-back measurements for either style of mag are about the same, if measured at the same point on the mag bodies.
BX-25x2 on the left, BX-25 on the right:

A quick measurement of a popular competitor's dual-magazine design showed a clipped-together width of about 2.5 inches, so the Ruger BX-25x2's decrease in this dimension is an appreciable and quantifiable 20%. Whether or not it makes any practical difference in actual use will be up to the user. Carrying either type of mag (Ruger's BX-25x2 dual-built-mag design, or two single-mags-clipped-together competitors' mags) on your belt, for instance, will still require a rectangular pouch approximately the size of a standard masonry brick; a curved/contoured pouch could be made slightly smaller and still work, but it's still going to be pretty chunky. Pouch flaps/lids must fit snugly and close securely to prevent the smooth, curved mags of either type from working their way out of a pouch through a gap and becoming lost during movement.
(to be continued...)