Newbie with a whole lot of trouble with his STI

[Indebt]

Hi guys i just finished shooting my second USPSA match today and like my first had a whole lot of gun trouble. First the gun only feeds round point bullets no flat point hollowpoints etc... It is very magazine selective out of 5 STI 140mm tubes with STi springs at 10 coils Dawson Precision followers and Arrendondo base plates it will work with three. With the other two the bullet either nose dives into the feed ramp or makes it partically into the chamber and jams. This typically happens when I chamber a round though it can happen with either when i am firing if i did manage to chamber a round which is rare with the two mags. I don't know what to do I am real pissed because it truely messes everything up. I'm ready either to send the mags off to Grams and have them tuned or be done with it and shoot a glock. Either way I'm out alot of money and all I want to do is shoot any help would be great.

[kimel]

Hello Indebt and welcome to the Forums!

You didn't say if the STI was new or used so will toss out a few things:

Likely to be a mag problem...especially if some mags work and some don't. Go get out your dial calipers and measure the feed lips on the mag that works and a mag that doesn't. Measure both front and back gaps. There is a chance that your lips on the mags that don't work are out of tolerance. Doesn't matter if these are new or used tubes...it happens.

Another possibility is the mag catch. A worn mag catch will allow your mags to sit lower than they should which can lead to feeding problems.

If your gun is new...how many rounds through it? It can take a few hundred rounds through a gun to get it to "settle in".

And finally, factory ammo or reloads? If reloads, check your OAL.

Those are the places to start anyway. Sending mags off to Beven is always a good thing to do. Brazos and others also do this service.

Hope that helps.

[Mistral404]

Indebt,

I have had Beven tune my mags before, he does an awesome job.

I had some problems with my Edge (.40) digesting its food.

I switched to SV mags and a SV mag release. The SV mag release was an immediate improvement.

BTW: AOL should be ~1.2.

Do not forget to polish your ramp, it does help. I have heard that a lot of .45s do not like anything other than round nose ball. If your STI barrel was like mine, it makes for a very snug fit.

and no offense to Glock folks but do not give up on your STI. You can send me a private message and I can recommend some good smiths to look at your gun if the mag catch does not do the job.

[Guest Larry Cazes]

Just a little more detail on the mag tuning. My suggestions.....

Measure the feed lips at 2 points, approx. 1/16" from the front and back, with a caliper. Adjust the front of the lips until the difference front to back is within .003".

I polish all of my mags at both the inner surface of the feed lips and inside the body of the tube using a dremel tool with a felt wheel and Flitz brand metal polish. This cuts way down on the resistance that the rounds have to overcome as they feed up and out the tube. As to springs and followers, I have very good luck with Grams Engineering new format parts which are pretty much drop in. Talk to Bevan Grams on the phone and he will let you know if you need to clip some coils from the springs when you buy them.

Aside from the magazines, you may still have issues with extractor Tension, etc. but I find that this tuning is worth doing on all of my mags to keep them happy.

[ErikW]

Also use a heavy enough recoil spring. An 11# isn't going to cut it with borderline ammo and mags.

[wide45]

A doublestack .45 is a special animal. It has been said that it is the most difficult configuration to make reliable. Be wary of taking advice from those whose experience is only from other calibers. I reccomend changing one thing at a time, so when it gets worse, you know what did it.

[Bruce]

I recommend sending it to Benny Hill with some ammo and paying him to sort it out. I had a pistol that gave me fits, it went to him and came back with better manners...nary a problem since.

[benny hill]

With a little care given to the feed ramp & extractor, new ISMI mag spring's, the gun will feed it all. Feed lips should be about .415

[benny hill]

With a little care given to the feed ramp & extractor, new ISMI mag spring's, the gun will feed it all. Feed lips should be about .415

[diehli]

I recommend sending it to Benny Hill with some ammo and paying him to sort it out. I had a pistol that gave me fits, it went to him and came back with better manners...nary a problem since.

As a testament to Benny's work, IIRC I was the only person on our squad (besides the guy shooting a Glock 17) at the Infinity match this past weekend that didn't have a single gun hiccup. Beven deserves a bit of that credit, too.

Color me pleased.