STI 9mm mags

[pevadijk]

I hate the spacers in my 9mm mags, can I just remove them and put a .38 super follower in it, or is the magazine spring different?

Brownells sells Teflon followers from Arredondo and the Magtech ammo that I shoot has as COL of 30,35mm so I guess it works without those spacer-things.

[Flatland Shooter]

I hate the spacers in my 9mm mags, can I just remove them and put a .38 super follower in it, or is the magazine spring different?

Brownells sells Teflon followers from Arredondo and the Magtech ammo that I shoot has as COL of 30,35mm so I guess it works without those spacer-things.

I use .38 Super Grams followers and springs in my Brazos tuned STI mags with no spacers. My bullet length is 1.20" (30.48mm) and I have no magazine problems.

Per Brazos, they recommend spacers be used for ammo with an AOL less than 1.20" on their tuned magazines. At 1.195" (30.35mm) your loads are close but a little short. It won't hurt to try it.

Bill

[TeamGE]

pedavdijk,

I highly recommend using spacer plates in STI mag tubes for the 9x19 cartridge. It does not matter how long you load your ammo. The reason for the spacer is to push the case forward so the case mouth can be controlled by the forward spacing groove of the STI mag tube. If there is no spacer, the side of the bullet will be the control surface, and allow the double column of ammo to be too wide, and cause stacking problems. The only way to get rid of the spacer plate is to replace the tube with a SV or SPS tube (different design tube all together), or have the entire STI tube reformed.

Keep the spacers, but glue them in place. They should not be loose in the tube. Use my FKS9-11 Follower Kit for the short mags, and the FKS9-13 Follower Kit for the long mags, and everything should be very easy to maintain.

[pevadijk]

The reason for the spacer is to push the case forward so the case mouth can be controlled by the forward spacing groove of the STI mag tube.

But if I try to make my ammo as long as possible, I might end up with ammo that's close to .38 super length (although I might tough the rifling before I get that far).

BTW, you don't seem to sell a FKS9-11 kit............

Edited July 28, 2007 by pevadijk

[Flatland Shooter]

On the negative side of running 9x19 long is you will need your gunsmith to run a throating reamer in your barrel so that the bullets do not touch the rifling.

On the plus side your Major 9 ammo will be too long to fit in the magazine of your non-major rated 9mm guns. Not 100% foolproof but it may help.

Just a thought.

[GentlemanJim]

HSMITH..Or Howard Smith here on the forum reforms 9mm sti mags for no spacer.

They work perfectly and he does very nice work.

We have had 10 mags done by him ...with ZERO malfunctions since he reworked them!!!!

Jim

[TeamGE]

pevadijk,

If you load your ammo longer, how is that going to push the mouth of the case forward, to touch the forward spacing rib? Check for yourself. Roll a 9x19 cartridge into the bottom of an empty STI tube, just like it would be sitting if you loaded it from the top. You will see how the cartridge relates to the spacing rib. I do sell a FKS9-11, it just does not show on my website.

Flatland Shooter is correct. Freebore length must be checked when running longer then normal OAL ammo.

GentlemanJim,

Though I personally have not seen one of the mags that Howard Smith has tuned, I have read on this forum that he re-forms the STI tube for 9x19, and does not need spacers at this point. I agree with this method, and as I stated before, this will work too, but requires sending your tubes in and having the work done, or buying them directly as 9mm mags. I look forward to seeing one of Howard's mag tubes one of these days.

This thread was started with the question of using spacers or not. In my opinion, the STI tube was not designed to hold 9x19 correctly. It must be fixed, either with spacers or re-forming. Otherwise, buy some new tubes that are made to work with the 9x19 from the start.

[DougCarden]

As I sit here, I have a couple of high places and wins with STI super mags that Beven tuned and I put in his spacer plates and follower kits for 9x19 last year and this year. I won my class at the Handgunner and got 2nd/5th at the Big Dawg Steel match as well with his mags/kits. You cannot go wrong with Beven's stuff, period. All my .40 mags will get his follower kits this fall......

Thanks for your products, Beven!

Doug Carden

[pevadijk]

My Edge is still fairly new, so I still need to find out how some things work...........but I guess I'll be needing the spacers ;-)

And thanks Mr. Grams, I just might buy some of your performance parts!

[pevadijk]

I bought some Grams spring/follower kit and made my ammo slightly longer (30,48mm) and it runs like a rabbit without the spacers ;-)

To this point I've shot around 1500 rounds without a hickup and I've dropped the magazines on purpose quite a few times, so they might get shuffled it the mags, but it just keep workings, although I needed to adjust the feedlips.........there were very W I D E!

BTW, the quality of the Grams stuff is way better than the standard STI follower/spring and with the original parts, its very easy to push down on the front and with Beven's stuff I guess it works how it should, although I had to modify my slidestop because it was activated with a round in the mag ;-)

Edited August 27, 2007 by pevadijk

[HSMITH]

I agree that the Grams kits are fantastic quality, I use them and recommend them.

I also agree with Beven that you NEED spacers, or an SV mag, or an STI mag that has been re-shaped to run 9mm without spacers. Your current setup runs, that is great, but I'll bet lunch that you are on borrowed time.

I went through all of this when I built my first 9mm, and there wasn't a lot of information to pull on how to get it running well. I KNEW the gun was right, but it wouldn't run consistently. Sure, it would run a thousand rounds problem free, but then it might puke 5 times in the next two mags. I loaded out to 1.220", and all the way down to 1.15", I tried everything I could think of and everything everyone else recommended too. I talked with all of the mag companies, mag part companies, top smiths and everyone else that would listen. I wasn't able to get it working for any period of time. It wasn't CONSISTENT. Common knowledge then is much as it is now, you either run spacers in STI mags or you run SV tubes. I hated the spacers though some of my heartburn with them could be eliminated by welding them in but I didn't want to do that either. Some study of the problems I was having told me I either had to re-shape the STI tube or run a spacer to get them to work. SV tubes are hard to find for most people and they are expensive, so I went after the STI tubes. I made a couple sets of dies, shot thousands of rounds and re-shaped the magazines countless times until I found 'the' settings I needed to get them reliable. Lots of time and money was spent getting them to work, but they work.

I personally use re-shaped STI mags and SV mags in my 9mm Open gun. I have done enough testing to know that the gun won't run consistently with anything else unless I use spacers.

I don't mean to rain on your parade, please don't take it that way. I am also not trying to sell anything, with your location I couldn't sell you anything even if I wanted to. If you can get Grams follower kits where you are then you should be able to get his spacers also. They are very nicely made and easy to fit. It would be a good idea to have some on hand.....

[Huston in Austin]

pm sent

Edited August 28, 2007 by Huston in Austin