How should a semi-auto feed?

L

Logistar

New member
Being new to semi-autos (and being concerned about my Taurus PT-111 being VERY RELIABLE), I was wondering if my Taurus was functioning normally. Here is how it works.

Looking at the rear of the barrel, there is a piece of metal that extends down from the end of the barrel (it is kind of like "ramp" - not sure what it is actually called.)

When the slide pushes the bullitt forward, instead of going straight into the bore, it hits way down on the ramp. This ramp is VERY "steep". Most of the time it hits low and slides up the ramp and everything is fine. When it DOESN'T slide up the gun jams and you can easily see that the bullitt only obscures about 15-20% of the diameter of the bore. (Not even close) Actually, it is slightly more reliable if I push the magazine upward when the slide comes forward (bullitt will initially hit the "ramp" higher and closer to bore.)

I actually have 2 questions.

1. Is this NORMAL? Should the bullitt hit very low and have to be deflected into the bore?

2. If this IS normal, it is normal to have jams when the gun is new? Could this "ramp's" angle be too steep or should it be polished?

Thanks guys! I really appreciate all the help!
 
Not having that specific gun to look at, it's hard to say if your description exactly matches what happens. However, it's pretty normal for many new guns to require a break-in of at least several hundred rounds. I pretty much discount stoppages in the first few hundred rounds when breaking in a new gun. The best thing you can do is shoot it a few range sessions, then evaluate it's performance.

There are also lots of things you can do to improve the gun, one being polishing the feed ramp. Either very fine emery paper 600#, or my trusty Dremel tool with polishing compound. The object is to make it smooth, NOT change it's contours! However, I'd shoot a few hundred rounds first...
 
My understanding of cartridge-feeding is based on 1911-like semi-autos.

Cartridge feeding is seldom 'straight-in' to the chamber, but a series of 'bounces' into the chamber. The process is highly aided by a properly-designed magazine, since the magazine dictates the initial positioning of the top round for feeding.

Two critical 'bounce-points' for cartridge-feeding into the chamber are:
1) The feed ramp below the chamber, angled at about 45 degrees, and either a part of the pistol frame or integral to the barrel design, and;
2) The barrel hood, situated above and behind the chamber and an integral part of the barrel.

Typically the bullet will first strike the feed ramp, then rebound upward from the feed ramp as the slide pushes the cartridge forward. The next collision of the bullet is with the barrel hood, where the bullet rebounds lower - aligning with the chamber as the cartridge is pushed forward into the chamber.

This process can be enhanced somewhat for feeding reliability by polishing of both the feed ramp and the barrel hood to slick up the surfaces where the bullet impacts on the way to the chamber. This is a very light and slight polishing to improve surface quality of these surfaces. Avoid any serious metal removal - polish only - since some ramps are plated, and removal of ramp plating to expose softer under-metal will/can result in a damaged frame.
 
Couple more thoughts.

If the situation changes when you hold the magazine up, that's tellin me there may be a problem with that magazine.

Also, if cartridge stripping from mag ok but bullet riding low, may need a little opening up of the forward portion of the magazine lips.

I believe that a defensive gun should be fully operational from the git-go. If it takes couple hundred rounds to break in so it functions reliably, wasn't finished when sold.

Sam
 
Your description is pretty good for someone unfamiliar with semi-auto pistols, surprisingly good.

But I think that Dorcas hit on a key point - are you slowly dropping the slide to see what happens when the gun jams? And/or is it jamming like this during normal firing? If it is only jamming like this while you slowly lower the slide - don't worrry about it. This is called "riding the slide down" and is to be discouraged with pistols. Some folks develope this as a bad habbit - hanging on to the slide as it drops while loading. It can cause the jamming you describe, improperly chambered rounds, and deformed cartridges. Your pistol is designed to feed at full speed, a slower moving slide will affect all kinds of things! The proper way to drop the slide is to bring it all the way to the rear and let it go.

If you are experiencing this jamming during normal firing, then something is deffinately wrong and we can start diagnosing weather it is magazine related, feed ramp, or ammunition - with a little more info.

Let us know, eh?
 
You guys are GREAT! I REALLY appreciate your help!

I have another post on here concerning the same topic but I guess I am still concerned about it. Anyway....

The gun has NEVER actually jammed after a shot was fired. I would SWEAR though that 3 or 4 times after firing a round that the slide went forward, stopped for maybe 1/4 second and then continued. (As if the bullitt hit the feed ramp, stopped, then slipped into the bore.)

My fears come from the fact that the gun jams when loading the first cartridge. After being told from my first post NOT to hang on to the slide, I now lock the slide back, insert the magazine, then release the slide. I do NOT touch the slide at all as it is released. This DID improve things as MOST of the time the gun does not jam but it still jams occasionally. Actually it jams very often when using Speer Gold Dot ammo. (124 gr. GHDP) It jams less often when using Federal "Hydra-Shok" ammo. It almost never jams when using Winchester Winclean ammo.

C.R. Sam may be correct as the spare magazine I bought seems to have a lot of "play" in it once it is inserted. Original mag has very little "play" and does seem SLIGHTLY more reliable.

As for the feed ramp, it is NOT 45 degrees. 25-30 MAYBE.

Being curious, I field-stripped the gun, placed a magazine in it, and placed the barrel exactly where the barrel would be during normal operation. Without the slide, I could use my fingers to push the cartridge forward to mimic the movement of the slide. When I did this, the bullitt contacted the "feed ramp "pretty low. I could see how the gun might jam. I honestly thought the the bullit should head straight for the hole and only occasionally hit below or to the side... with the contour of the end of the barrel guiding it in. I didn't expect that the bullitt was supposed to HIT an "obstacle" on it's way in. Like I said, I am new to semi-autos.

BTW - when the gun jams after releasing the slide, the cartridge is in the EXACT same position as when I push the bullitt forward into the feed ramp with my hand. In fact, if you hold the gun JUST RIGHT, despite the fact that it gas been thoroughly cleaned, it looks like there is a slight indentation or possibly a slight copper-colored discoloration at that point of impact. (I may be imagining things now!)

Sorry to be so long-winded but I was trying to give you more details (as requested). Summing up:

I have fired about 130 rounds in the Taurus PT-111.
Gun occasionally jams when mag is inserted and slide is released.
Gun NEVER jams after firing a shot. (so far)
Bullit occasionally hits bottom of the feed ramp and just sits there when loading the first round.
I tried locking the slide and releasing it and I tried pulling the slide all the way back and letting go. - Still have jams.

I will try and take the gun back to dealer but he has been closed recently due to illness.

Thanks again to all of you. If you have any more thoughts, send 'em my way! I won't carry this weapon if I don't have confidence in it. (Wish I'd found TFL before I bought it!)
 
I have found Taurus to be a good gun but like any new gun you must disassemble and clean it.

Remove all factory grease and clean the parts with petroleum based lubricant like Remoil. Do not clean with silicon lubricant like Hopps in the orange bottle because it will not breakup grease.

After cleaning my gun the feed ramp was shiny with mirror surface and feeds hollow points and semi-waddcutters perfectly.

Good luck,

Shok
 
:confused:

Maybe this could help...

searanim2.gif




Best,

New_comer
 
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I notice one thing- you say it chokes on hollowpoints, but seems to feed non-hollowpoint (AKA "ball") ammo OK. This is a fairly common thing, but by no means acceptable on a defensive pistol. The reason for it is that the nose of the HP bullet is shaped in a manner that causes the cartridge to 'catch' on something (part of the feed ramp, the edge of the chamber, whatever). Ball ammo often feeds more reliably because its, well, round.

What I would do is this:

1. Buy a bunch of cheap ball ammo and shoot the gun a bunch. Like, several hundred rounds, or maybe a thousand. This will eliminate the 'break in' problems. Use this time to see if it is related to any particular magazine(s), or to any factor of grip or gunhandling, or to cleaning (DISREGARD if this has been done already).

2. Start looking for a brand of hollowpoint ammo that will feed flawlessly. This will be expensive, and do not be surprised if you get great reliability with one type and crappy with another. My P232 (a quailty gun) will shoot Hydras all day long, but can't abide Silvertips. So buy a few boxes of everything, and shoot until you have one that looks good. Then buy a bunch of boxes of that kind and shoot ALL OF IT to make sure the danged thing works. (DISREGARD if this is not a defensive pistol)

3. If that doesn't work, start doing a few at-home gunsmithing tricks, like feedramp polishing. ASK FOR TIPS before you do it, because once you polish stuff off, you can't put it back on. ;)

4. Failing that, take it to a gunsmith.

5. If that doesn't work, sell it to someone you don't like. :D

Mike
 
I really want to thank all of you for those excellent responses to my original post. Thanks to you, it looks like I have everything figured out.

It appears that as long as I use Federal Hydra-Shok (sp) AND I pull the slide ALL the way back and release it (instead of just releasing it from a latched position) it seems to feed perfectly now.

Also... since this gun has NEVER failed to feed the next round AFTER firing a shot, I am confident that I can fire 11 rounds with NO problems. - That is assuming the gun is carried with one round already in the chamber (with safety on).

The only trouble I MIGHT have would be when getting the gun "ready" to carry. - I could deal with a jam then. (Just hope that I don't NEED to use that second magazine!)

I DO plan to polish the feedramp and check out different brands of ammo. Hydra-Shok looks pretty good right now. I will let you know how it ends up. I will probably give it a month or two before I report back.

Again, thanks to all!!! :)
 
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