Well, as I've mentioned in most of my other threads, I've been very interested in boosting the capacity of my XD since I bought it during the BS "assault weapon" ban, and thus all of my mags were the limited 10rd capacity. I have a 4" XD in 357sig, with an EFK drop-in 9mm conversion barrel. It's kinda weird, because a while back I bought a 10rd 40s&w mag that was supposedly altered to work with 9mm for my conversion barrel. I think I only got a chance to try it once before my untimely demise, and remember having a few ftf issues. I wish I had tried just using 9mm rounds in the 357 mags I already had, because just recently I tried them out, and they fed fine. the 40 mag holds the rounds tilted down slightly, which I believe is why they jam. It might help if the EFK barrel ramp were tweaked slightly, but it looks like the mag is the main issue. Anywyas, as far as the high capacity mag weirdness... I bought a full-capacity SA 357sig 12rd mag, and then an AGP mag extension and extra power spring, which gives me a nice 15rd backup mag. Then I did several weeks of price shopping for Mec-Gar mags, as well as the 30/32 rd National & Promags which everyone seems to hate. I found a great deal on those mags & an upLULA at Trophy's Hunting Gear. I have to pass on this find to you, now that I have received the products and can verify that they are legit. They have the Mecgar 13rd 40(357) & 18rd 9mm XD mags for $19.55! So I got one of each of those. They also have the dreaded Promag 32rd 9mm XD mag for $21.76. I know everybody says they are trash, but I figured it would at least be good for novelty and possibly fun on the range; but the main thing that motivated me was the possibility of the so-called "assault weapon" ban returning in a permanent way, as it sounds like may happen with our current political situation. Since I got my XD back in the day, it didn't come with a speedloader, so I also had to get the much-loved upLULA(for $22.64!). Using the upLULA, I was finally able to get the last two rounds into my SA mag w/ the AGP extension, and that worked just fine. So here's where it gets weird: I loaded the Mecgar mags, which have gotten unanimously positive reviews. I was pleasantly surprised that they really did look good and flush when loaded in my XD. The 9mm mag worked great with my conversion barrel, but the 40 mag jams(wtf, ftf)! I was shocked, I was using jhp rounds, though I'd never had that problem with my SA mags. So I bought some fmj wwb 357sig rounds at Wally World(Ugh, I feel dirty giving $ to that wretched corporate incarnation of evil!), thinking they might feed better. However the tips of the rounds were flat, not rounded as I had hoped. But I thought they would probably still feed easier than the jhp's. No dice, still jammed! WTF?! I haven't heard of ANYONE else having a problem with Mecgar mags! WHY?!! Like my problem with the "converted" SA 40 mag, I think the issue is with the mag and how/where it holds the round. However, as suggested with my problem with the inproperly converted SA mag and my conversion barrel, the feed ramp might have been an aggravating factor? Now obviously the 357sig barrel is the one that came with the gun, so I don't think it could even be as much of a factor as the 9mm conversion barrel(which is to say I'm pretty sure that's NOT the problem), but I have to wonder about it for one reason. I had the barrel hard-chromed. I really hadn't even shot the gun much and "broken it in". I probably haven't even put much more than 100rds through my XD, sadly(I haven't even shot it in 5 years now!). So I have to wonder if chroming the barrel almost out of the box may have made the feed ramp a little... pickier? Again, I still think the issue is with the magazine, since I have NEVER had a ftf with my SA mags. Any advice on how to correct this issue? Hang on, it gets weirder! I checked out the dreaded Promag. First off, YUCK! it came coated with some kind of sticky black grease. The bag it came in still has the grease print in it. BTW, I'll try and post some pics of all of this gear soon. Anywho, after wiping that nasty gunk off of the Promag, I tried loading it using the upLULA. It's hard to say for SURE, because I'm easily distracted and the Promag doesn't have any holes drilled in it to indicate how many rounds it is holding(boo!), but I THINK I was able to get 35 rounds loaded in it! WOW. I didn't think it would even hold 32, and probably stop at 30. I had read reviews of the Promag 20rd 40s&w mag where people said that even using a mag loader they were not able to load anywhere close to 20. But when the mag is loaded into the XD, it is a little loose and sits a hair too low, and the rounds don't want to feed unless I press the mag up firmly into place, then they feed fine. I'd appreciate any suggestions on how to fix that little glitch. This is where it gets REALLY weird. I don't know why I even tried this, but for some reason I tried to put some 357sig rounds into the Promag 32rd 9mm mag, and they fit! I was able to load 15rds of 357sig ammo into the mag before something bloacked them. I could tell that the mag wasn't full, but something got in the way. There's no dimples in it like the SA 10rd mags, so I'm not sure what they were hitting. I didn't feel like taking the mag apart to investigate, but I just might if I get really curious and bored. The weirdest thing is, the 357sig rounds would feed from the 9mm promag without even needing to push it up like when using the ammo it was made for(9mm)! HOW WEIRD IS THAT?! The 9mm Promag works better with the 357sig rounds than the 40s&w Mecgar mag!!! What gives?! I am so thoroughly confused! Does anyone have any ideas on how to solve my magazine issues???