IDPA legal mags for STI/SV

[Mikey]

Anyone familiar with STI/SV guns,

I just got finished with a new IDPA gun in 40 caliber built on an STI standard
dust cover frame and slide. I have 10 pre-ban hi-cap standard length
(126mm) mags with carry base pads which I bought for dual use, IDPA and
IPSC Limited, but, alas, the gun won't fit in the IDPA box with these mags.

I see in Brownell's where SV makes a "duty" mag, which is advertised at 2
rounds less capacity than the standard, but they don't list a length. I also
see that STI makes a 120mm mag but they say it's for the 3.9 frame only.
With the 126mm mag inserted in the gun there is a 10mm gap between the
base pad and the gun butt so it appears the 120mm with the same pad
would fit but I would like to know for sure before I buy them.

Which mag do IDPA shooters use in their guns? Any help will be appreciated.

Mikey

 

[TaxPhd]

Mikey,

Is yours a bull barrel, or standard with a bushing? Bull barrel won't work for IDPA (or at least it didn't used to).

 

[Mikey]

TaxPhd,

I guess I should have explained that I'm not a novice IDPA shooter. Your question is a reasonable one. I'm really hoping to get an affirmative answer on the 120mm mag length being compatable with the standard grip profile.

The rest of the gun is IDPA legal. STI standard dust cover frame, no mag well, STI standard profile slide, MMC low profile adjustable sights, standard stainless full length guide rod, standard weight Nowlin ramped barrel with bushing, no extended mag release etc.

I thought the mags would be flush fit since they were listed as the "standard" mags, but they aren't. I have been told the 120mm will work with the "carry" base pad. Looking for confirmation...

Mikey