Teach me about STI vs SV mags

jtischauser · May 5, 2013

I'm trying to sort through all of the BS to get setup with some 170mm mags for my open gun.

Will SV mags fit in an STI gun?

What do you run for 170mm mags? The gun I'm building will shoot 9mm.

bsdubois00 · May 5, 2013

SVI will SORTA fit your STI gun. I have both Sv and STI mags for mine. Chances are 99% you will have to tweak the svi mag. Use a file and just take the mag catch hole up a smidge as well as they may have to be squeezed a tiny bit with a vise. Literally it's maybe 5 min of work. I really like the SVI mags I have and in fact those are the ones I use with the STI mags being my backups.

backer · May 5, 2013

100% STI tubes here.

Grams follower and spring (9mm needs spacer, get this one http://www.shootersconnectionstore.com/Shooters-Connection-Joey-Hardy-9mm-Spacers-170mm-P533.aspx)

Dawson base pad.

I polished the crap out mine externally and internally so they fall freely from the gun and helps with reliability when feeding.

My understanding is that the old SVI mags will work in both, but the new SVI mags require some work to get them to play nice with STI.