[orangeninja]

http://www.thehighroad.org/showthread.php?s=&threadid=65565

link above:confused:

[Brian Williams]

How many rounds are thru it, does it need an new spring kit??? What is the feed ramp like, does it need polish?

Check your mag springs and followers. Does the bullet nose dive or hit the top of the barrel hood.

[orangeninja]

The nose will actually go into the chamber, but it seems to get stuck about half way. Both mags are brand new...and should work. Maybe the feed ramp needs polishing....how do you go about doing somthing like that?

[1911Tuner]

The nose will actually go into the chamber, but it seems to get stuck about half way.

Probably stem bind. Check the case on a jammed round for a crescent-shaped mark just below the mouth. Advise...

Check the breechface for roughness. Check the extractor for easy function.
A weak magazine spring can also be a player in certain circumstances.

Try different ammo. Some pistols are persnickety about the overall length
and will exhibit stem bind if the cartridge is a little longer or shorter than it
likes.

EDITED: After reading the thread...Are you letting the slide go at full speed during the reload, or riding it to battery? Autopistols generally need to be
fed at full speed unless fine-tuned for feed reliability.

Standin' by...
Tuner

[orangeninja]

Letting the slide go at full speed. The cartridge works perfectly in my other Sig 229...so I doubt it is the ammo. It may be a weak recoil spring? I guess I can try another one. What else may it be? should I just take it to a smith?

[1911Tuner]

alduro said:
Letting the slide go at full speed. The cartridge works perfectly in my other Sig 229...so I doubt it is the ammo. It may be a weak recoil spring?

Check for that crescent-shaped mark on the case and ckeck the extractor for free movement. Got a feelin' it's one or the other...

[orangeninja]

What if it does have that crescent shape? I haven't noticed it...but I will look. Why would the extractor have anything to do with feeding a bullet?

[1911Tuner]

alduro asked:

What if it does have that crescent shape? I haven't noticed it...but I will look.

If the mark is there, it's coming from a condition called Stem Bind. Basically,
it's the bullet nose hitting the underside of the chamber, trying to break over to horizontal to ENTER the chamber, and the moving slide getting it
into a bind at three points by forcing the side of the case into the top of the throat, the nose of the bullet into the top of the chamber, and the rim
at the breechface.

Lowering the angle of entry as it tries to go to horizontal can help. Breaking the sharp corner at the top of the throat/entrance to the chamber
will help. Polishing the roughness on the breechface will help. Thoroughly
cleaning the breechface with a stiff toothbrush and solvent may be all it needs. A toothpick will also help get it all.

There's a chance that this is purely and simply a magazine problem. Try
to borrow another magazine to see if anything changes. Most autopistol
failures to feed are due to bad magazines, and since the Sig is such a sound, reliable design, I have to suspect it.
----------------------------------


Why would the extractor have anything to do with feeding a bullet?

As the slide strips a round from the magazine, it causes the case rim to slide under the extractor hook. The extractor has to hold a certain amount of sideways tension on the case rim in order to reliably extract it from the chamber after the round fires. If that tension is too high, the rim can't slip
under the hook and break over to horizontal to enter the chamber. The
slide stops just short of going to battery.

If the extractor's movement is limited by dirt, crud, or a piece of grit so that
it can't move sideways to allow the rim to get under the hook, the effect is
the same as too much tension.

I'm not too familiar with the Sigs, since we don't see many around here.
I don't know if yours has an internal extractor...like the 1911...or an external extractor mounted on a pin and powered by a coil spring.

If it's internal, remove it and clean the channel. If it's external, you can
try spraying some carburetor cleaner around the area to remove any
build-up that may have gotten behind it. Put a drop of oil around it when you're through.

Hard to diagnose this kind of thing sight unseen...All we can do is point you in the right direction and see if you can nail it down.

Luck!

Tuner

[tc300mag1]

Just wondering if your using slide stop to release it or slingshooting the slide

[orangeninja]

I will look at it, strip it down and take a gander.

If I slingshot the slide the round will chamber with no problem. It does go in a little rough though it seems, like maybe some resistance from somewhere. If I simply drop the slide stop I get the failure.

[1911Tuner]

alduro said:

maybe some resistance from somewhere. If I simply drop the slide stop I get the failure.

A fresh recoil spring may help, but it's a band-aid fix for the real problem.
If the gun is right, it should strip a round and go to battery with a spring
that's half the rate of the one specified. F'rinstance...If I can't get a
street gun to feed and go to battery by pushing on the rear of the slide...with one fingertip... with the recoil spring removed I start lookin' for a reason why.

It's usually somethin' simple...

Luck!

Tuner

[orangeninja]

I'll break it down tonight and take a looksee....It didn't do that for the first 30-50 rounds. I may just take it to the local smith....its supposed to be a defensive weapon...I must have darn near 100% reliability.