My M&P9 and Ameriglo "Hackathorn" sight sizing

[scootle]

Hi all,

First of all, I do not mean for this to be a "negative" criticism of this product as I believe my issue(s) may be unique unless other people have similar experiences that can verify a trend. With that in mind, I would like to find out if other people have experienced any sizing issues with the "Hackathorn" sight setup offered by Ameriglo (SW-433B).

Some backstory... I have a S&W M&P9 full-size (dated Aug 2009 production). I used the OEM S&W factory sights in a "Stage-1" class with Louis Awerbuck and one of the diagnoses he made for my shooting was that the 3-dot setup was pretty clearly confusing me during sight alignment (he could see my eyes trying to focus and refocus on both during acquisition). As a check/fix we blacked out the rear dots of my S&W sights for the duration of that class and voila... problem (mostly) solved! Thus, I knew that I wanted to find a sight setup with a single front dot and minimal distraction on the rear sight. When I saw pictures of the "Hackathorn" sight configuration offered by Ameriglo, I was convinced this would be the sight configuration for me. After acquiring a Glock 22 EXO that came equipped with the I-dot Pro setup very similar to the "Hacks," I was sold that I wanted to convert all my training/practical pistols to this configuration.

In May 2011 I ordered and received a set of the "Hacks" for the M&P9 (there was a short backorder) and had them installed. At the time, nothing seemed to be amiss. I took the pistol on a short checkout session at the local indoor range and everything seemed OK. A few weeks later on a second range visit, the front sight literally slid right out of the dovetail with finger pressure at some point during my session. Uh oh.

I contacted Ameriglo and Rick, the support specialist, was very helpful and understanding. We arranged for a mail-exchange of my clearly under-sized front sight for another unit. No sweat.

Fast forward a little while and I finally had the new sight installed around August by the same gunsmith that I used for the first round. Upon inspection and fit-checking he told me that it seemed that this sight was also on the borderline of being under-sized for my dovetail. However, he suggested that since it wasn't finger-loose that he could peen or "mushroom" out the sight edges a little to allow a better purchase on the dovetail of my pistol. We checked and re-checked the sight in the store and it appeared that this time it would be OK.

I ran a check-out session (approx 100 rounds) through the pistol at the local range and all seemed well.

This past weekend, I attended the 2-day "Stage-2" class with Louis Awerbuck (I will post an AAR later) and to be honest, for the first day and a half, the sight was awesome. Being the first real "run of the gun" in a more practical application than range/lane shooting with this configuration, I really appreciated the much faster and clearer sight picture I could achieve with the Hacks while drawing and moving, etc. I thought I was all set!

Long story short (sorry I'm so long-winded!), sadly, about half-way through day 2 (300+ rounds later), lo and behold my shots were suddenly going w i d e right. Uh oh. On a whim I checked my front sight between a strings of fire and it had indeed shifted again, this time about 1/8" to the left. I completed the rest of the shooting day with a loaner M&P9 (factory config, newer production lot) from the range without further issues. Louis Awerbuck suggested that one potential solution (that might be fairly permanent) is to actually stake the sight into the slide and then monitor it carefully.

So aside from anyone else who might have had similar experience and might want to chime-in, I am curious if perhaps my pistol itself might have something going on with the dovetail size/tolerance that is making it incompatible with 2/2 front sights at this point? The OEM factory sight did not have any such issues, but in all honesty, I'd think the factory has a bucket of sights in all shapes and sizes to match up until it fits properly to a given slide.

Don't get me wrong, Rick@Ameriglo has been very responsive and understanding and I have already contacted him for further action. Rick mentioned to me that he had another M&P user with the opposite problem, where the Ameriglo part was too big for the dovetail and required filing to fit. I have full confidence we will be able to figure something out, even if it means I'm SOL and need to find another sight solution. In all honesty, I really like this setup and I'm not sure who else makes a similar configuration that would be a candidate.

Is this a potential issue I should also pursue with Smith & Wesson? I'm not sure what the solution might be other than sending me a new slide somehow?

My other concern is that I need to get a handle on this little problem since as a training/defensive weapon, I obviously need it to be reliable. If anything, anyone else who might run this setup, obviously make sure you double/triple/quad check how secure the front sight blade is before you commit to trusting your life to it.

Thanks for any feedback.


PS Some pictures below of how it looks now. I'll post a follow-up once I have sorted out the path of action.




PPS some added info from this thread... Grant posted that the base of the M&P front sight should be ~0.253". I just calipered my OEM front sight and it came out to 6.52mm (0.256") -- uh oh?

[DJK]

My "Hackathorn" is my 3rd front sight on my M&P9 and it did the same thing. An internet search showed it to be a common problem with lots of firearms. I just shimmed it and it has stayed in place for over 1K rounds. I added a drop of white paint to the base to give me an instant visual if I suspect that it has moved. Locktite with or without a shim is also an option.

[subzero]

Looks like you have an oversized cut for your front sight dovetail. Not that big a deal, and probably within factory specs for what's allowable. After all, they had an oversized front sight to give you.

I think your best option is to get a slightly oversized front sight. If your guy already peened your sight to fit and that didn't work, it's time for a new sight.

Instead of peening the sides, try hitting the bottom to force the sight up in the dovetail. It's like shimming it. This can get a marginal fit to nice and tight since it forces the angled contact areas to be flat, vice your guys way of peening the edges.

[scootle]

My "Hackathorn" is my 3rd front sight on my M&P9 and it did the same thing. An internet search showed it to be a common problem with lots of firearms. I just shimmed it and it has stayed in place for over 1K rounds. I added a drop of white paint to the base to give me an instant visual if I suspect that it has moved. Locktite with or without a shim is also an option.

Yeah, scribing or otherwise marking the sight alignment is probably in-order. What did you shim your sight with? When I hold the slide up sideways to light, I do not see any gap under the sight base (but I do see little pinpricks of light at the sharp tips of the dovetail, obviously).

Looks like you have an oversized cut for your front sight dovetail. Not that big a deal, and probably within factory specs for what's allowable. After all, they had an oversized front sight to give you.

I think your best option is to get a slightly oversized front sight. If your guy already peened your sight to fit and that didn't work, it's time for a new sight.

Instead of peening the sides, try hitting the bottom to force the sight up in the dovetail. It's like shimming it. This can get a marginal fit to nice and tight since it forces the angled contact areas to be flat, vice your guys way of peening the edges.

I'm not sure what you mean there... how would you get anything under the sight base to push it upwards into the dovetail? The M&P sight is only inserted side-ways... no access from below.

I'm thinking I might contact S&W just to see what they might be able to do. Rick@Ameriglo got back to me and didn't think they would have any sights that are almost +0.003" over their existing production stock. He said maybe they will spec a +0.001" on the next production run.

More later.

[Bowie Tactical]

I have installed alot of the Ameriglo sights and others on M&P's one thing I have found is a huge variance in the dovetails on the guns. Some are lose and some are tight to a wide degree. The Hack sight is no more than my sight design for Ameriglo with a different front sight ring around the tritium so I have obviously installed alot of them. I have found some way tight and some lose. The other problem sight makers have is folks that think the sight should slide in in real easy and then not be lose when shot so they have to ride a thin line. If you sight goes in easy then the dovetail needs crimped and if it is way to tight the sight needs fitted. It not always someones FAULT it is just the manufacturing from different companies and tolerences run. Knowledge of what to do will solve all of these problems.

David Bowie

[scootle]

I have installed alot of the Ameriglo sights and others on M&P's one thing I have found is a huge variance in the dovetails on the guns. Some are lose and some are tight to a wide degree. The Hack sight is no more than my sight design for Ameriglo with a different front sight ring around the tritium so I have obviously installed alot of them. I have found some way tight and some lose. The other problem sight makers have is folks that think the sight should slide in in real easy and then not be lose when shot so they have to ride a thin line. If you sight goes in easy then the dovetail needs crimped and if it is way to tight the sight needs fitted. It not always someones FAULT it is just the manufacturing from different companies and tolerences run. Knowledge of what to do will solve all of these problems.

David Bowie

Agreed. As an aerospace engineer I fully understand how tolerances can stack up worst-on-worst (which is pretty clearly what I've got going here) to cause fitment problems. I just wanted to make sure nothing on either side was out-of-spec per se that would require replacement outright. It's pretty clear that my pistol is on the "large" end of the M&P sizing spectrum since other owners have also experienced this issue.

I'm going to see if the gunsmith can shim or dimple the sight base a little to give the few thousands that are missing to keep this thing in tight. As it is right now, I cannot remove the sight by hand, so it's at least that tight. It's just clearly jumping around under recoil and/or when the slide heats up under sustained strings of fire.

At the worst, Rick@Ameriglo said the next production run of sights maybe early next year could be spec'ed a hair larger and maybe I can try again at that point if it should break loose yet again along the way.

Thanks again for all the replies.

[subzero]

I'm not sure what you mean there... how would you get anything under the sight base to push it upwards into the dovetail? The M&P sight is only inserted side-ways... no access from below.

Sorry, my phrasing earlier was lacking. With the front sight off of the gun, use a spring loaded center punch or similar tool to peen the underside of the front sight. This will cause a small amount of material to displace. This displaced material will cause the sight to sit higher in the dovetail, which could help solve your fitment problem.

Your deal sounds like the fitment is affected a bit by heat, so you shouldn't need to do a lot to get it to stay put.

[scootle]

Sorry, my phrasing earlier was lacking. With the front sight off of the gun, use a spring loaded center punch or similar tool to peen the underside of the front sight. This will cause a small amount of material to displace. This displaced material will cause the sight to sit higher in the dovetail, which could help solve your fitment problem.

Your deal sounds like the fitment is affected a bit by heat, so you shouldn't need to do a lot to get it to stay put.

Yeah, after I thought about it a bit, I figured out what you meant. Thanks for the clarification.

And yeah, I wonder if the heat of sustained fire might be playing a bit into why my sight ended up moving even though it seemed like this second go-around was set. I did do a couple of 10-round mag dumps on some strings (even though I didn't need to, we had the option) just to give the pistol a good workout in a setting where I was not hamstrung by 1-shot per second lawyer/range rules...

In some ways, I'm glad I found out that the sight was still not set in a class/training setting for sure! God forbid I'd ever need it in any other social setting, but you know what I mean...

[Beat Trash]

My agency has had a few M&P slides in which the factory front sight was a bit loose.

The fix the armors use is to place the slide in a protected vice. Then place the ball portion of a ball peen hammer in the center of the dove tail. They then take a second hammer and administer a "love tap" to the top of the first hammer. This will decrease the opening of the dove tail slightly. When done correctly, one is not able to notice any change to the slide by looking at it. The amount of the "love tap" is increased through trial and error until the desired effect is achieved.

Obviously this is done without the front sight installed.

One of the armors actually learned this while attending armors school for a different manufacture.

Before our complement of officers started to be decreased, we started with about 1,200 guns being issued out 6 years ago. The above mentioned fix was due to some variances in the dovetails.

Before anyone wants to use this as justification as to why the M&P is a POS compared to their favorite brand, this variance can and does happen to other brands of firearms as well.

[scootle]

Minor thread necro, but I think this deserves an update since S&W customer service really does deliver.

I contacted them a while back and described the issue, the rep just said they'd send a FedEx label so I could send them the slide for inspection.

I enclosed a note describing the issue, with the Ameriglo sights still installed, and also added a request, if possible, to have them go ahead and swap out my "old" black MIM striker assembly for the revised "silver" stainless revision.

One week turn around total... got the slide back today (obviously a brand new one) and the gunsmith went ahead and moved my aftermarket Ameriglo sights over to the new slide as well as included my old "black" striker assembly in the box (the slide has the stainless assembly installed). He/she definitely didn't have to send the old unit back, but he did, so that's a nice little touch.

Very slick. They honestly do stand behind their products... this is how you keep your customers loyal and coming back for more. (Which is why I didn't hesitate to put a 9C on order a few weeks ago since "it was time"... )