I have found some 40rnd TripleK mags for sale and I am trying to find out if they are worth trying.  I recently purchased 4 40rnd Colt mags that would not insert in my Armalite and would not seat in a Bushmaster.  The mags cost under $20, and the company is offering a guarantee for function.

Thanks for any input.
Nik

Im no mag expert but I didnt know Colt made 40 round mags. In fact, I didnt know Colt made any mags at all!

In any case, Triple K mags are junk. The only 40 round mags worth having at all are the Sterling 40 round mags, and they are quite scarce. If you do find them, they go for a MEGA premium price, say $100 per mag.

Short of that, it's usually best to stick with quality USGI 30 round mags.

Thanks for the info on the Triple K mags.  The other mags had Colt stamped on the floor plate and came from Bushmaster Firearms.

I compete in IPSC 3Gun matches and have found stages were an extra 10 rounds would make a difference, but not sure a $100+ mag would be a worth while investment.

Also, just checked out your FDCC website.  Sounds interesting, might see if I can make it out to one of you shoots sometime soon.

Thanks again.
Nik.

The other 40rd mags that are reliable are the PMI and Federal Ordinance brands.  The finish on these mags are blued compared to the parkerized Sterling mags.  That guarantee is worthless, they will replace a nonfunctioning mag with another useless mag.