We recently conducted a second test of Glock OEM G19 10 round reduced capacity magazines. Ten 3rd gen G19's (ser #GXP, MBG, PMW, PUU, PYT, RRY, VKS, XBF, WNB, WWK) were used; all of the pistols had previously proven extremely reliable feeding and functioning when using standard capacity Glock OEM 15 & 17 round magazines shooting Federal AE9FP 147 gr FMJ practice ammunition, as well as Federal P9HST2 147 gr JHP and Winchester RA9T 147 gr JHP duty ammunition. Ten new OEM Glock G19 10 rd reduced capacity magazines were used. The intent was to fire 100 rds through each pistol using AE9FP practice ammunition fired from a G19 reduced capacity magazine. However, after 500 rounds, ALL of the pistols exhibited magazine related failures to feed and function. The test was stopped and the OEM 10 rd 2183 followers were all changed to OEM #3 followers. An additional 500 rounds of AE9FP were fired through the pistols--again ALL of the pistols exhibited magazine related malfunctions...

Note that in the mid-2000's we did a similar test where we used ten reduced capacity 10 rd OEM G17 mags, along with 10 standard capacity OEM 17 rd G17 mags--ALL of the 10 rd magazines demonstrated feeding malfunctions, while NONE of the standard capacity mags had any problems. In that test, several of the OEM 10 rd G17 magazines exhibited improved function when #3 followers were substituted, but NONE of the reduced capacity 9 mm Glock magazines functioned as reliably as standard capacity 9 mm Glock magazines.

For those in states which idiotically limit magazine capacity, Glock 26 10 rd OEM magazines function reliably--so using a G26 or cut G19 is a possibility, but not ideal due to the short grip inhibiting magazine changes. The neutered S&W 10 rd OEM M&P9 & M&P9c magazines seem to have no problems reliably feeding, however, they often fail to drop free, unlike the standard capacity S&W OEM M&P9 mags which drop free with ease. S&W OEM 10 rd M&P45 magazines generally function reliably.

For the record, I despise neutered magazines; their is NO logic behind the artificial bureaucratic mandates that require their use, especially given that the increased likelihood of inducing a malfunction using a reduced capacity magazine could prove catastrophic in a defensive encounter...