25 round mag doesn’t fit a18 - Armscor Precision Inc Rock Island TM22 25 Rounds .22LR Rifle Magazine

I purchased after reading an earlier review the magazine is missing the notch to clip in. The magazine does not fit the A18 without modification. So I used a grinder to cut the notch and it now clips in. I used the standard 10 round magazine to mark the notch with a permanent marker and began cutting.