9mm Mag Questions - Old Style SVI

[Desmo412]

I was hoping some people with experience could answer a few questions I have about magazines for my STI open gun. I have a full set of STI mags that I purchased tuned from FGW when Bobby built my gun in 2012. I am trying to put together a set of SV mags though as I prefer the simplicity of not needing a spacer.

I managed to get my hands on an unused 170mm old style SV mag. The feed lips measure .305-.310" from back to front. I'm guessing this is a bit tight as my STI mags measure .350-.355". What is the general consensus on feed lip dimensions for 9mm mags? I can find plenty of info on .40 mags, but not much on the 38/9 mags.

This mag will hold 29 with a Grams spring/follower. I was planning on sending the mag to Adrian at magblueprinting.com to have it tuned for 30 round capacity. He does a really nice job squeezing the indentation smooth at the bottom of the mag so the follower doesn't flip when full. I went to TTI to order a follower and spring and I noticed he no longer carries the Bolen-style follower. He has replaced it with a "Gen-2" follower that looks more similar to a Grams. Now I'm sure these work great but I KNOW the Bolen-style follower was the way to get 30 rounds as it is a much lower profile than the Grams-style. Does anyone have any experience with these new followers? He claims they do NOT require any tuning on the tube. I will be using his new 4G2 basepad.

Thanks

Glenn

[Ace38super]

Dont mess with those feed lips. The SVI mags are shaped and spaced differently than STI. They are also harder than STI so its unlikely they are bent. Just make sure it fits the mag gage with any Dawson pad as it vould be tight. With Grams a 3mm will fit but sometimes a 4mm wont.

[Desmo412]

I have a 3mm, 4mm, and a 4G2 pad from TTI available to use, so I'm covered on basepads. I will test the mag on Thursday to see how it runs with the feed lips at their current dimensions. If I put a Bolen-style follower and spring in the mag with a 3mm pad, I can fit 30 rounds of 9x19. When I put the 30th round in, the follower slides below the indentation in the tube and flips....which allows a round to fall below the follower. The tuning will take care of that problem. Hopefully someone can shed some light on my questions about the new TTI followers.

[Desmo412]

BTT. Hoping to get some replies on this topic before I send the mag off for tuning.

[Ming the Merciless]

If your sending it to Adrian for tuning, he'll correct the feed lip dimensions if they are not correct.

[Heckler]

I have a 3mm, 4mm, and a 4G2 pad from TTI available to use, so I'm covered on basepads. I will test the mag on Thursday to see how it runs with the feed lips at their current dimensions. If I put a Bolen-style follower and spring in the mag with a 3mm pad, I can fit 30 rounds of 9x19. When I put the 30th round in, the follower slides below the indentation in the tube and flips....which allows a round to fall below the follower. The tuning will take care of that problem. Hopefully someone can shed some light on my questions about the new TTI followers.

I am using the Gen2 TTI followers with the arradondo spacers. I tuned my feed lips to 38S, 38SC,9mm, 9x23---.355"-.360" and have not had a single issue since.

Used info from these threads to get them running:

http://www.brianenos.com/forums/index.php?showtopic=99973

http://www.brianenos.com/forums/index.php?showtopic=141880&hl=+mag%20+dimension