When MDT dropped their poly/metal magazines, I thought they were going to be that magic sweet spot. Reliability of the metal up top, with the weight savings of polymer throughout. Unfortunately, after running them for a short period I noticed that my bolt was starting to bind. After closer inspection I I found that the front corners of the polymer shaved off.
That results in the magazine inserting too far and the bolt binding.
All of the loading/shooting occurred while prone, off a bipod. So, not a particularly abusive scenario. I have two of them and it happened with both. One more than the other. I suspect that's the case because I was using one more than the other. To be clear, I think that MDT produces good products. I even ordered a couple more metal mags from them after I discovered this problem. Just thought I would share in case others are considering that particular product. YMMV.
That results in the magazine inserting too far and the bolt binding.
All of the loading/shooting occurred while prone, off a bipod. So, not a particularly abusive scenario. I have two of them and it happened with both. One more than the other. I suspect that's the case because I was using one more than the other. To be clear, I think that MDT produces good products. I even ordered a couple more metal mags from them after I discovered this problem. Just thought I would share in case others are considering that particular product. YMMV.