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I've been shooting WWB 115 grains in local USPSA matches. The 9mm full size P320 is new and the mags haven't seen a lot of use. During several stages I have an issue where the fired round is ejected but the slide doesn't strip off the next round and feed. It just jambs partially forward and I have to rack the slide to get it to feed.

Has anyone else seen this with a P320? Does it not like WWB?
 
Posts: 101 | Registered: September 17, 2006Reply With QuoteReport This Post
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Assuming the gun is properly lubed, the common denominator in a number of these "failure to feed" threads seems to be WWB.

I'd try something different, like 124gr, before getting too concerned about it.

On a side note, I've had three friends ask me to look at their pistols and all three were so dry they squeaked when anything moved. They must soak them in solvent to get every last be of lube removed. After a detail strip and lube all three said that they couldn't believe the difference and wanted to know what I did...
 
Posts: 1221 | Registered: October 01, 2013Reply With QuoteReport This Post
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GP229, thanks! The problem has hit in all three matches I've been in, and generally early on in the match. Before each match I've cleaned and lubed the gun and I'm mildly liberal when it comes to lube.
 
Posts: 101 | Registered: September 17, 2006Reply With QuoteReport This Post
Freethinker
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To be precise, I believe what you’re describing is probably a failure to chamber. “Feeding” is what the magazine does, and a failure to feed would be if the cartridge wasn’t pushed up to where the slide could contact it. That could conceivably be the problem, but very unlikely with three separate and new magazines.

That said, I agree about lubrication and using more powerful ammunition, but especially the more powerful ammunition because you’re already lubing properly. With weak ammo, the slide may move far enough back to eject the fired case but not far enough back to pick up the next round from the magazine, or other issues can occur.

Depending upon the type of lube you’re using and the ambient temperature, things may improve later in a match just because the gun and lube are warmer. If you are limited to using the wimpy Winchester ammunition, you might try a light lube like TW-25B.




“Most men … can seldom accept the simplest and most obvious truth if it … would oblige them to admit the falsity of conclusions … which they have woven, thread by thread, into the fabrics of their lives.”
— Leo Tolstoy
 
Posts: 36989 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
When you fall, I will be there to catch you -With love, the floor
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quote:
I'm mildly liberal when it comes to lube.



First mistake. The gun does not need a large amount of lube. A light sheen on the slide rails and a few other contact points. Grease is not used on the academy guns. slip2000 EWL is and they work reliably.

quote:
you might try a light lube like TW-25B.



That lube fell from favor as they found it separates with age. When it happens in the syringe style, it's junked.


Richard Scalzo
Epping, NH

http://www.bigeastakitarescue.net
 
Posts: 4368 | Location: Epping, NH | Registered: October 16, 2004Reply With QuoteReport This Post
Freethinker
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quote:
Originally posted by rscalzo:
That lube fell from favor as they found it separates with age. When it happens in the syringe style, it's junked.


To each his own, but I have used it for many years and 1. I have never seen it separate in the syringe and 2. I have fired guns with no problems or apparent change in functioning that had been sitting in a safe for as long as nine months after the lube was applied.

It does separate in the 8-ounce tub I have, and I simply stir it back together before loading a syringe. The reason I like TW-25B is for how it ensures reliability in cold temperatures. I have had slow slide speed malfunctions with other lubes. That’s not to say there aren’t other lubes that would also work, but although I’m always willing to consider alternatives, I’m not one to hop to the current lube du jour. I’ve tried Lucas grease that claims an effectiveness range to –20°, but it’s pretty viscous, and that makes me a little nervous in my climate; TW-25B is rated to –85°, IIRC.

What do you recommend for cold weather use?




“Most men … can seldom accept the simplest and most obvious truth if it … would oblige them to admit the falsity of conclusions … which they have woven, thread by thread, into the fabrics of their lives.”
— Leo Tolstoy
 
Posts: 36989 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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There used to be a good article on the Mil-Comm site in regard to using TW-25b.

It is actually a semi dry film lubricant, so the liquid is basically a carrier and it is not unusual for it to appear dried out after application.

It went on to state that if you see white, it's probably too heavy an application. All you need is to see that the surface is wet, or barely white for heavier applications.

You are supposed to clean all contact surfaces with Alcohol and apply it very sparingly using a brush of cloth.

I use it exclusively on internal parts and since I am in FL I use Slide Glide or Lucas grease on the rails.

I detail strip and clean all parts in an ultrasonic cleaner prior to TW-25 application and have seen as much as five oz reduction in trigger pull after proper application. (Sig's and 1911's)

I also use TW-25 on the rails if using a .22 conversion kit on my Sig's and it made a difference in ammo sensitivity there as well.

YMMV!
 
Posts: 1221 | Registered: October 01, 2013Reply With QuoteReport This Post
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I'm in balmy South Carolina and more subject to heat than cold. Using CLP on bearing surfaces and wiping down afterward.

So far the issue is usually the slide moves forward without stripping a round off the magazine. However, at the Steel Match a couple weeks ago the slide actually locked back. I have five mags total, two that came with the gun and three SIG branded others. I believe the two that showed issues yesterday were one of each, though I may have moved the followers around. The factory mags came with black followers and the others have gray.
 
Posts: 101 | Registered: September 17, 2006Reply With QuoteReport This Post
Freethinker
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Short-stroking in which the fired case ejects but the slide doesn’t pick up a new round is usually due to insufficient slide movement: it goes back far enough to eject, but not far enough to allow the round in the magazine to clear the slide and be pushed forward to be chambered. Assuming there isn’t some other problem such as insufficient or wrong lube, excessively powerful recoil spring, or mechanical interference with the slide due to the shooter’s thumb or something similar (all of which you discounted, I believe), it’s no doubt due to insufficient cartridge power. The 115 grain Winchester practice stuff is often implicated in various slow or insufficient slide movement malfunctions.

If the slide lockback occurred when there were still rounds in the magazine, the most likely cause is getting one’s thumb under the slide catch lever. Not that that’s what happened to you, but it’s a possibility. A magazine could have been at fault, but that seems unlikely if it occurred only once.




“Most men … can seldom accept the simplest and most obvious truth if it … would oblige them to admit the falsity of conclusions … which they have woven, thread by thread, into the fabrics of their lives.”
— Leo Tolstoy
 
Posts: 36989 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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While I'm not aware of any operator error, I've not shot in matches for several years. It could be the trigger monkey. I've shot 1911 in matches before, these are the first matches with the P320.

I've been planning on reloading anyway, so this gives another reason. I'm mostly discounting any disfunction in the gun, for the most part it runs. Since my reloads were also lower end loads that may have been the same issue.
 
Posts: 101 | Registered: September 17, 2006Reply With QuoteReport This Post
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FWIW, I have a P320FS .40 and a P320C 9mm, both early 2015. Never had any issue with the nine.

Did have the same feed problem as yours with the .40. Occurred several times during the first 300 or so rounds. Apparently a break-in issue, since it disappeared later with use. Some guns need a break-in...some don't.

I'm familiar with the rap on WWB 9mm as underpowered. Have never really understood it though. My 122gr lead reload velocities are far slower than WWB or any oher factory load. However, they have worked reliably with my 9mm Glocks, P320 and P239. Try some different ammo, but I'd put my money on a simple break-in issue.

If you haven't marked your mags with a unique ID, do so. Also check the gun and mags for any burrs, roughness, anomalies, etc.


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An expert is one who knows more and more about less and less until he knows absolutely everything about nothing. --Nicholas Murray Butler
 
Posts: 3883 | Location: Northeast | Registered: June 29, 2006Reply With QuoteReport This Post
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Reloaded rounds on the light end of the scale seemed to work fine with the Gray Guns fat guide rod. Didn't get to test the reloads with the factory rod and spring.
 
Posts: 101 | Registered: September 17, 2006Reply With QuoteReport This Post
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