Tuesday, October 22, 2019

Resolving Tanfoglio Witness Magazine Issues

This post is in regards to my own observations and my particular model pistol, a Tanfoglio Witness P-S imported by EAA circa 2012.  If you're reading this because you're troubleshooting or looking for magazines or a review, consider that we might be thinking about vastly different pistols.  Let's take a moment to paint a more appropriately muddied picture.

These both are full-size polymer-frame EAA/Tanfoglio Witness pistols in 9mm
It is a rather common occurrence there may be many different unique products associated with an overarching product family name.  Figuring out which specific model you actually have and searching for parts is made difficult by the reluctance of manufacturers, marketers, and retailers to make differentiating information (i.e. unique model numbers or names) prominently available.  Just as "Motorola Razr" might be a smart phone or a flip phone, a "Tanfoglio Witness 9mm" might be one of several different things.  The Witness family covers steel frame and polymer frame pistols in different frame sizes depending on caliber and manufacture date.  They're also subdivided into compact and full-size variants within that distinction.  While most of the Witness models are based on the CZ-75 design, there are also M1911 clones under the same name. As far as magazines go, EAA does provide a serial number lookup tool to help owners identify their model and the requsite magazine.  Adhering to time-honored tradition, this tool only works on some browsers.  Bear in mind though, if a large fraction of retailers don't provide any compatibility information more specific than a model family, confidently searching for parts might still be difficult even if you know the specifics of your product and the desired part. 

Walking back toward those specifics, my pistol is a post-2005 full-size polymer frame variant (SKU: 999044).  This is described as "New Frame Special", which appears to be a variant of what is more often simply referred to as the "small frame" pistol.  This seems to make sense, as it is a Witness P-S (polymer, small frame) as opposed to a Witness P, which is (to my knowledge) an earlier larger frame model.  To be appropriately confusing to the incautious, the frame is marked "Witness P-S", while the slide is marked "Witness P".  Again, this information is useless since almost every retailer uses "Witness P" and "Witness P-S" interchangably if they mention it at all.  The magazines which are compatible with my pistol are #101900 (16 round), #101920 (10 round blocked), #101921 (25 round).  The magazine which shipped with mine is #101900. 

Original Magazine #101900

I have had this pistol for several years and have put 300-400 rounds through it.  While I'm comfortable with it and generally satisfied with its performance in comparison to what it replaced, it has always had a tendency to occasionally misfeed within the first few rounds out of a full magazine.  With round nose FMJ, the issue is rare, but with flat-nose or JHP ammunition, this tendency can be frustrating.  The misfeeds take various forms depending on the bullet geometry and cartridge OAL.  Flat-nose and JHP rounds may get stumped against the bottom edge of the feed ramp.  Round-nose ammunition may do complete nosedives if the OAL is short.  When the problem manifests, it will tend to persist for the next 3-4 rounds before disappearing. Until recently, I had never used anything other than round-nose FMJ.  At the time, I simply attributed this very occasional fault to either my loading of the magazine or perhaps the need for some break-in.

Hornady JHP with short OAL stumped into feedramp
Complete nosedive with Remington UMC round-nose FMJ

In response to a partial-feed issue which arose when changing ammunition, I used Cratex and a wool buff to ease and polish the edge and bottom corner of the extractor to keep it from biting into case rims.  I polished the feed ramp, breech face and the side of the breech opposite the extractor.  In all, this reduces the amount of force required for a round to slide under the extractor.  This solved the particular ammo-sensitivity I was having, and I wondered if I had just solved the more longstanding misfeed issue at the same time.  On the second magazine after my polishing work, I wound up with a handful of complete nosedives using both Remington UMC and PMC Bronze 115gr FMJ.  It seems I had solved one of two unrelated faults contributing to the misfeeding tendency; the prime suspect was now the magazine.

With a bit of fiddling and observation, I had a handle on what was happening.  The problem seems to be an issue of magazine geometry more than anything else.  With only a few rounds in the magazine, the rounds in the tapered section seem to be well constrained and will reliably stack against each other with the top round tightly against the feed lips.  When there are >10 rounds or so in the magazine, the rounds in the tapered section of the magazine may not stack uniformly.  They tend to pivot around the wrong side of the ribs, allowing the top several rounds to fan out vertically.  One way to induce this mis-stacking is to push down on the nose of the top round.  You may feel the stack shift as you depress, and when you let go, the top round will be held only by its rim.  The front of the case will be unsupported and ready to nosedive when stripped.  The placement of the retention dimples in the feed lips seems to exacerbate the problem by giving the round something to pivot against. 

Tight stacking with only 3 rounds
Splayed stacking with 13 rounds
Unsupported round will easily pivot down when stripped

While I'm sure someone would suggest that this is all caused by a collapsed spring, I doubt that for three reasons: The problem has been manifest since the magazine was new.  The misfeeds never occur at the end of a magazine.  Adding a filler block inside the magazine to increase the spring force does not change the behavior, and manually applying an excess of force to the follower with the floorplate and spring removed will not prevent or remedy an irregular stacking condition either.

How big of a problem is this though? While it can be intentionally induced as described, the condition also seems to arise naturally during loading and handling.  The fact that the slide keeps the stack depressed while closed means it can occasionally recur even if the magazine was stacked tightly when it was first inserted into the pistol.  A magazine which is sluggish either due to fouling or a weak spring will probably be more prone to this mis-stacking when the slide opens.  Sometimes this mis-stacking can be cured by slapping the magazine on its side, though it often can't.  A small tool or pocket knife can be used through the magazine catch slots to push the stack back into alignment, but that's hardly a practical solution. I think it's big enough of an issue that I am willing to write off this magazine as having a flawed design. The best fix is replacement with something different.

MEC-GAR MGWIT9SFAFC

As I mentioned, it's hard to confidently find parts when retailers don't know what they're selling or don't care to communicate any amount of unambiguous identifying information.  As far as I know, if you want a different magazine to replace a #101900, your only option is a Mec-Gar MGWIT9SFAFC.  This is listed (and stamped) as a 17-round magazine, and it fits well.  The feed lip and transition geometry do significantly differ from the original magazine.  The follower is different primarily in that it matches the narrower transition geometry; this also means they aren't interchangeable.  The spring is significantly longer and has more turns.  The end result is a magazine which reliably stacks perfectly every time.  The aforementioned method of inducing mis-stacking does not work on the Mec-Gar magazine.


So far this sounds like a perfect fix.  I ran several dry-cycle drills without fault, trying to induce misfeeds with flat-nose rounds all the while.  I eagerly loaded up a magazine with said problematic flat-nose FMJ and spent it on steel plates.  I was a bit distracted by the satisfaction of getting the ammo to finally feed that I lost count and was a bit confused when the hammer finally dropped on an empty chamber; the slide didn't lock open when the mag was empty.  I depressed the mag release, and the magazine happily stayed put.  Only after a bit of wiggling would the mag come out.

Follower rounded over on Mec-Gar magazine
The plastic follower barely catches slide lock on its edge, and after only a few dry-cycle drills and a single mag in live-fire, it had rounded off and wedged against the side of the slide lock instead of lifting it.  Now it would no longer reliably catch the slide lock.  Okay, I guess a LRHO is kind of a convenience, but now the mag won't drop because it wedges against the slide lock.  So even though it solved the misfeeding issue brilliantly, the Mec-Gar magazine introduces a new inconvenience.  Granted, I only have one magazine to base this on, but at an overall cost of $33 each, I'm not exactly going to buy enough magazines to do a statistical analysis of this failure mode.  At this point, I see two options: cut off the corner of the follower so that it neither lifts the slide lock nor wedges against it.   This defeats the LRHO, but it's the easiest to do.  Alternatively, one could repair and reinforce the edge of the follower where it engages the slide lock.  That is what I opted to attempt.


My first attempt was simply to cut a piece of spring steel strip to match the profile of the follower edge and epoxy it in place.  After some final dressing, this looked fine and worked perfectly when tested manually.  I loaded a single round in the magazine, shot a steel plate, and was rewarded with an open slide.  I removed the magazine, and the steel reinforcement fell out on the floor.  The epoxy didn't bond at all to the follower.  Based on appearance and toughness, I had assumed this was glass-filled nylon, but perhaps it has a lubricant additive. After a few other attempts, I resigned to the fact that bond strength was going to be very limited. 


I changed plans and came up with a reinforcement which relied more on mechanical support than the adhesive bonding.  I drilled a small hole in the follower to retain a section of 3/32" steel rod.  The hole is deep enough to reach the centerline of the follower, ensuring that the end of the rod is fully captured.  I used ScotchWeld 2216, as this relatively flexible epoxy tends to have good adhesion to troublesome plastics. The bond strength is still relatively weak, but it's the best I had.  At this point, the LRHO works correctly and the follower edge is resistant against deformation. 

I have no idea if the problems I've experienced are common or even repeatable.  I do not know if there are other alternatives beyond the two magazines I've described.  If you found any of this information useful, then I suppose that's a good thing.