S&W Pro CORE 9L Open Gun Build

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twoicebergs

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North of Oakbank, South of Selkirk, West of Beause
Just as the title says, I want to build a reasonably competitive Open Gun using my M&P Pro Core (5" barrel). Maybe it is just a foolish passing, but I see there have been good results and easy access to parts if you live south of the boarder. So for those that have purchased aftermarket parts, where did you get them and/or how did you get them to Canada? If you were sneaky, please don't post. With my job, I can not risk being denied access into the USA.

This is what I need:

Short reset trigger and method to reduce trigger pull to about 2-3 lbs. I had thought of keeping many of the original parts and just doing a trigger job, but the current safety/trigger will not work for for a minimized reset and short pull. Apex or other.

A second slide would be nice to have, including milling it for weight reduction. I could always take the original slide and barrel with me on a trip south for porting, but if I have read correctly, Magna-ported barrels with slide cuts are not as effective as barrels with matched (screwed on) compensators. I have seen a few, but again, no one will ship to Canada.

A barrel in 9mm that is designed for major loads. KKM, Storm Lake or other about 5.5-5.7" threaded. This I can find, but a package with a matched compensator and slide would be ideal.

Any other ideas as more than welcome. If it just isn't worth the effort, I will have a fairly new Pro Core with a Burris FF3 for sale soon. It shoots very nicely, but I don't need 4 Production guns in the safe.
 
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I recently tried a M&P Standard gun with an Apex trigger and it was a huge improvement! The trigger had a nice pull but the reset on his wasn't great (he did say something else needed to be completed so it would feel better) It also had a mag funnel you could shove a horse down, so they're available. I have no idea where he picked it up but I'm sure he didn't break any laws to do it. It seemed like a great choice for three gun because of it's simplicity but I'd say it wouldn't be my first choice for IPSC.
 
Smith now makes a Pro Core with a comp'd barrel, Brownells carries Apex, as does CTC (http://ctcsupplies.ca/collections/triggers/products/apex-forward-set-sear-trigger-kit) the comp spring kit will reduce the pull weight on the trigger (down around 2 lbs), but does so at the cost of a softer reset. You can somewhat offset this by gently tweaking the trigger bar inward (very gently, or buy a spare) and this will firm up the tactile feel of the reset. Note that most people are installing Apex parts with no polishing, this can improve things greatly - all Apex stuff is top quality and will polish up very nicely.
 
storm lake ships to canada, I'm sure if you emailed them they would make an extended and threaded barrel (doesn't even have to be threaded, any smith can do that). Most smiths can make a comp as well.

the FSS from apex can now be bought in canada, I believe wanstalls carries them, among others.

Really the cheapest way to do this is have the gun built in the states and import it as a while, then the import fees are only $200
 
As an update I have since acquired an STI Trubor, but I am actively working on putting the M&P Pro Core together as well. I have a Burris Faast Fire III mounted on the slide that is holding up well after the first one started to loose the lens. I did buy a barrel, compensator and springs from Carver Customs, but KKM and Carver didn't check to ensure they had the 9mm barrel in the correct box, so I got a 40 cal barrel in the 9mm box. Of course no one, including the importer knows what to do to get the exchange of the correct barrel done. There goes another few more months before this project can get completed as I need a replacement. If someone wants a a 40 cal KKM barrel, PM me. I have it listed in the pistol parts sale section.

Earlier this summer I started to due some part shaping to smooth out the trigger. I started with the USB by rounding the edge. This significantly reduced the gritty feel to the trigger pull. I will say that the new Pro Core has a better trigger out of the box than the plain M&P. Recently I did some work on the sear and noticed that the Pro Core already comes with the performance sear that is shaped similar to the one in the Burwell PDF. I took a bit more of the rear lip off and polished it. I should have stopped there with a very smooth 4-5lb pull. I then started to remove a bit off the upper side of the sear only to find the 0.012" I took off was enough to cause the firing pin catch to release if the slide was lifted slightly. It looks like the performance sear already had the minimum sear thickness to function properly. I still didn't really like the longer reset, so I will just get the Apex FSS kit for the better trigger and new sear. I doubt I will get the flat faced trigger.
 
AriZona Tech this time around.

I put in the Apex FFS sear and trigger kit ordered from IRG, but I used my self ground firing pin blocker as it was smoother than the one that shipped in the Apex kit. I also used the original trigger spring from the Pro Core. My trigger pull is now 2.6 lbs. I could do a bit of polishing and remove a slight amount of material to bring it under 2 lbs, but I am very happy with the trigger set-up now. The remaining parts (9mm threaded barrel, SS magwell, slide-racker, and extended mag release will make their way to me within the next week.
 
Just waiting for the thread-locker to cure. The only things left are some magazine extensions and a slide-racker!

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Today I took it out for a sight in, chronographed the major loads, and ran some drills and steel. The first thing I noticed was the S&W magazines did not lock in position; however, the 3 ProMags did! I suspected I might have to do some trimming with the 10 round mags, but not the 17s (pinned to 10). It definitely needs 1/2" or longer base pad extensions with the larger magwell.

Overall it shoots pretty well, but I had more muzzle rise than expected with the major PF loads (using 7.1-7.4gr of 3N37 powder - PF171-177). It certainly isn't a Trubor or Checkmate, but it doesn't weigh in as a heavy-weight either! With lesser loads (PF137) the muzzle control was pretty good and the gun cycled normally, but it was just on the edge for the selected spring weight. It was interesting to see the much higher PF compared to a Checkmate or STI with the same ammunition. Perhaps lowering the PF a bit or switching powder may help the gas production, but the 9mm casing limits the powder choices.

Disclaimer: This barrel/compensator combination is designed for MAJOR loads. Don't try this on a barrel that is not designed for this purpose!
 
I have put about 400 rounds through it to test it and fix a few issues. The first one was I was getting light primer strikes. I thought it might be the primers or my press, but for this gun it turned out to be the Upper Striker Blocker (USB). With the Apex FSS it tuns out the trigger bar timing was out enough to have the firing pin just catch the blocker, but not always (Nearly every unfired primer had a dent and usually went on the second engagement). The USB catch on the firing pin is damaged beyond repair and the USB edge is beat up as well. The good news is this is Open gun, so there is no requirement for the USB to be installed! Removing the USB has also lightened the trigger to just over 2 lbs.

Here is a side view of the recoil in slow motion shooting a Bill drill with 9mm Major ammunition. It is snappier than my STI Trubor in 38 Super, but the gun is significantly lighter, especially at the compensator end.


I don't know why it won't embed properly!

Magazine extensions made from a cutting board!

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Last installment. (maybe)

Since I am running 9mm Major loads I decided to experiment with a heavier compensator and also by closing the side holes to force more gas out of the top to reduce muzzle rise. The problem with being on the north side of the boarder is that it takes forever to get parts, assuming you can even find them for some guns; so out came the welder and a few other tools to attach a 95g brass weight to the compensator.

Comp weight screwed by twoicebergs, on Flickr

I also had a complete failure of the Springer Precision Extended Mag Release. As I started shooting a few days ago, the mags just started dropping from once in a while to almost after every shot! No one knows why it happened, and Springer already has another one on the way to me!

Springer Precision MR by twoicebergs, on Flickr

When I get a video of the gun in action I will post it.
 
Shooting 9mm Major Power Factor loads (1,348fps), 124gr FMJ RN bullets, 6.9gr of VV 3N37, 1.14 OAL. It shoots pretty flat and runs perfectly

Also, with a lighter recoil spring and factory Centaure 124gr 9mm ammo (PF about 142 with this gun barrel combo), the gun cycles very well as long as you have a strong grip. I tried 2 other brands and some 137 PF home-made ammo, but it wouldn't cycle the slide with that ammo.

 
Time for an update.

With the added weight to the compensator it actually started to bend at the threads and the bullets started hitting on the lower edge of the compensator, resulting in the bullets going up to 10" high while I was figuring out what was going on. I rebored the compensator, but it once again moved enough to cause contact with the bullets.

With just the aluminum compensator in place, the gun does not perform as well as my STI Trubor or STI Match Master. I still may try a steel compensator, but I have pretty much placed this project on hold until a relatively inexpensive steel compensator comes my way (maybe a .223 comp could be adapted). Also, with only 1/2" or less of threading even a steel compensator may not be able to take the stress on recoil.
 
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