I took my NEA to the shop to buy mags and found as I had previously suspected that some spear mags fitted ok and some were tight and awkward to get out.
The clear ones seem to be a bit skinnier than the black ones. If possible take your rifle or (just the lower half of it) and test the fit.
Not sure if this is just a spear mags thing , or whether matching mags to magwells is a common problem. They should be tight enough not to rattle, but loose enough to drop free under their own weight when empty IMHO.
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