Does this look right?

[rdhjr1973]

The picture with the lower sitting round is my 10rd mag and the higher is my 9 rd mag.

I have an XD 40 SC and was inspecting the gun because I've had some premature slide lock issues while mag still has ammo in it. I no this can be thumb placement and haven't ruled it our completely. However I was checking to see if the bullet was tripping the slide lock from the inside and clearance looks good with both factory mags. I did notice though, that depending which mag was in, the sit differently. Any ideas?

[smittty]

In the middle pic, is the cartridge pushed all the way to the back?

The cartridge won't engage the slide stop. I think you could be hitting it with your thumb.

[rdhjr1973]

In the middle pic, is the cartridge pushed all the way to the back?

The cartridge won't engage the slide stop. I think you could be hitting it with your thumb.

Yes, it's all the way back.

After checking the clearance with both mags, I agree with you.

I had read a few articles saying that some of the XD 40's had a problem with the knob inside the slide lock being to long and hitting on the bullet, causing premature slide lock.

After checking the clearance was good, I figured it must be my thumb but then I noticed how different the bullet sits depending on which mag. Not sure if this could be causing my issue or not?

[FourLoko]

Strange. I used to have a problem with the slide NOT locking back on a Glock because my thumb was on the slide stop. You're saying it locks open while you still have rounds in the mag?

[rdhjr1973]

Strange. I used to have a problem with the slide NOT locking back on a Glock because my thumb was on the slide stop. You're saying it locks open while you still have rounds in the mag?

Exactly, not every time but enough.

[JTROKS]

It's possible that the bullet will hit the lever that engages the mag follower upon empty. Insert an empty mag into the lower and take a picture of that lever in relation with the mag's follower. If there's some room to trim the lever then that may be needed.