M4 Standard Magazine/Spring

[Boon]

Hey crew.  I'm the new owner of an M4 (11707) and I've only fired about 50 slug/buck shot cartridges through it.  After a basic cleaning after the range, it's now only accepting a quantity of 4 - 3" slug cartridges in the magazine.  Depending on the manufacturer, I can fit a total of five 2-3/4" cartridges, but some are just a little too long and I can only fit 4.  Not quite 5.  I didn't have this problem until after the range.  It originally held 5 as designed, but now it's as if there's something jammed in the magazine, preventing a full load.  I never removed the spring beforehand.  Just a basic cleaning.  I have since removed the cap, spring, and follower to check for blockage, but found nothing.  After reinstalling the spring, I'm having the same issue.  The only thing I can think is that the spring is damaged (no sign of obvious damage upon inspection), or compresses oddly while loading, and prevents a full 5 load.  Anyone else have this issue?  I'll take any input you all have.  Thanks.  

[aznwhip]

Make sure the spring is fully in the follower cavity and not caught on the follower edge somehow?

[Boon]

I see now this topic has been posted several times.  If someone can pass along a link to where I can buy a standard spring, that would be great.  Not the 7 round extension spring.  Just the standard 5.  Thanks.

[Boon]

2 minutes ago, aznwhip said:

Make sure the spring is fully in the follower cavity and not caught on the follower edge somehow?

That's worth a check.  Thanks.