Benevolence

No problem. I recommend you get the two Kuhnhausen 1911 books (they can be ‘acquired’ online as PDF’s too) if you’re going to start tinkering.

They’re located referenced to the slide stop hole; the hammer hole is 0.016” above and sear hole is 0.252” below. So, 0.268” nominally.

Hi all, I’m working on fitting a kkm threaded 355 bull barrel to a fusion slide and stuck at 0.034” locking lug engagement. The lug recess on the barrel and slides are on approximately 0.055” and I’ve got the hood fit. From looking at wear marks from fitting as well as looking online, it appears the barrel near the muzzle end needs fitting to allow it to engage more. Also, the barrel appears to engage the lower side of the slide more when locked up. My question is, do I remove material from the barrel upper or lower sections highlighted (poorly) with a sharpie (nevermind near the locking lug though), or from the lower surface of the slide that interfaces with the underside of the barrel. If the answer is the barrel, do I use a file or is a lathe necessary? I was thinking to use a dowel and sandpaper (320-1200 grit) to grind down the lower barrel support section of the slide near the muzzle. I’ve done a kart ez bushing barrel and it was somewhat painless. The guy at kkm said just to remove material from the lug recess but that is not the limiting feature it appears.

Got the bottom milled out and dremeled the top round to fit with the frame but still has a bit of a shelf for thumb webbing. Taped the frame off and JB welded first layer to blend out the frame fitting. Ugly as sin but feels better. Drilled out 2x 3/32” holes for the cross tension pins however I’m not thrilled with how little plastic is left on the frame to hold it on. Also having done a JB weld & 36 grit on my M&p, and how beat up my hands got, I am going to try some hockey tape, and it will help hold the tungsten backstrap on as well. At this point I’ll have created two abominations, never mind my 2011’s. Next up is lightening the slide, sending it out to Primary Machine for SRO cut, and getting the tungsten guide rod with 1911 springs on. Hoping this total adds on 12oz or so to the frame and take a few off the slide. I shot the gun first time this weekend, without the tungsten modifications though. Did 750 rounds of that Winchester steel case crap and no hiccups. Very happy with the lowered recoil and striker springs. Maybe a bit too low on the recoil though; it seemed to come back high on target. If anyone is wanting to do a tungsten backstrap, ebay has some bucking bars for $30 that you can cut between the countersunk holes and have a perfect length. I did an Archimedes water test and it’s close to 19g/cc, so I think they’re the 90% tungsten, ~5 & 5% copper/nickel.

How does the cone-comp setup work? Do you put it on a bushing non-threaded barrel with silver solder and the end of the cone is threaded or part of the compensator? As for titanium, it should stop sparking once it’s oxidized a bit; if fresh unoxidized titanium is exposed to air it does that. Actually a hazard for the titanium powder in additive manufacturing with it. The right part of the flame with a bit of heat should make it stop right away, if it bothers you.

Got the tungsten backstrap started today. 8.6oz and going to put some cross pins on top and bottom then build it up to the grip profile with some jb weld then 36 grit finish. Got to mill the bottom flush as well.

I feel like the way the M&p fire control group works allows it to have a better trigger than a P-10F or a glock. That said, the HBI trigger and some springs have really gotten the trigger to where I’m happy with it; very close to the M&p with apex. That said, I like the grip and slide better on the p10.

Great, thank you! I just went through all my mags (OEM base plate) and pushed in as much as I could and still didn't get them to touch. I definitely see how a rear relief cut could make it a non-issue with mag extensions that may not go as high on the tube. I almost think at this point I'd be better off using $240 towards practice ammo than +3/4 on my mags. Hoping to get that tungsten backstap done tomorrow

Alright, thanks. I guess I was basing that off the previous posts I saw; I think Earlan357's and you had made a comment. I suppose I'll cross that bridge when I get to it.

Quick question: I’m looking to put some 140mm magazine basepads on but I’m wanting to make sure the ones I get will prevent over-insertion and breaking the ejector. It looks like the factory ones do, and probably CZC’s. Do Hennings do this as well?

Sear spring too weak or trigger bar is getting pushed out from under the sear. Put more bend in the trigger bar perhaps. I would suspect the trigger bar. Take the slide assembly off, and see if you can get the problem to repeat itself. Maybe be able to see the problem easier that way. Edit; out of battery actually sounds likely as well. Does it fire if you push forward on the side after slamming a mag in? If so you’ll need to either increase recoil or decrease striker spring.

Are you having rounds get under the follower or just binding and preventing spring tension on the upper round? Supposedly if you use a rod and bottom out the ammo in the mag out every 5 rounds or so during loading, it helps them arrange a bit more organized (MBX's video on youtube https://www.youtube.com/watch?v=X1VUOVSBUlY). Probably combination of geometry and friction.

Usually with a direct optic-slide fit you can get the optic quite a bit lower than with mounting plates. May not be much but it can start to feel a bit high.

I had the same issue. Old LEO trade in M&P9 1.0; installed Apex trigger but sear housing was old and small hole/spring. I bought this part (https://www.midwayusa.com/product/1004477881?pid=546264), swapped over Apex sear and removed the magazine safety parts. I had several 2 round bursts and dead trigger before installing the new sear housing (and I used the Apex sear spring as well).

I may be mistaken but I thought the glock gen3 guide rod was drop-in compatible. The work that a few others (including the ‘next steps’ in that link) did was to get larger diameter guide rods and use 1911 springs. @aandabooks Opening up the guide rod hole to a larger diameter in order to accommodate a larger guide rod.

From the sounds of it, gen3 glock guide rods are compatible? Maybe minor shortening of the length? Source: earlan357 https://czfirearms.us/index.php?topic=107144.0 Im currently milling some cheap bucking bar tungsten (90W,~5Cu,5~Ni) I got off eBay to try to copy some of the previous ones people have done.

Thickness and deposition temperature vary quite a bit. Any chrome/nickel that's electro/electroless deposited will typically be 0.003" thick on surfaces unless it's "flash chromed" where it's 0.0002" thick. Tank plating in a solution is usually lower temperature (23-100°C) but PVD coatings can get up to 500°C and start to distort parts enough to need refitting (happened to a slide of mine that was chromium nitrided CrN). DLC can be catered towards wear resistance or lubricity (diamond vs graphite structure) and is typically low temperature (~100-200°C) deposition so you don't have to worry about distortion as much. DLC is also thin (~0.0002"). As PCPEMark said; the PVD processes are very thin and will show the same finish as pre-deposited. Only thick coatings like hard chrome can be polished back down without taking it off.

It isn’t very thick, I believe about 1/8”, but I trust it enough; the thread engagement on mounting plates isn’t much either and this is a really hard/tough stainless steel (guessing 416). If I’m not mistaken, the barrel weight doesn’t act to cause much muzzle flip and actually reduces it. I realize it does move down and back slightly. Though it’s effect on the timing/unlocking of the barrel/slide may be more influential.

Okay, fair enough. I’ll do a moderate lightening on the next 2011 build and see how it does.

Ya, it cycles quite nicely. I had the old sear block in it which had a light sear spring and I got some sear flutter (2-3 round burst) but the new sear block & stronger spring will resolve that, I believe. Still contemplating taking out more in the extractor area. That’s assuming stripping of the round requires the momentum of the slide, but the same spring should (in theory) bring a slide forward faster (same potential energy, lighter mass). I often get messed up on when momentum or energy is more important. If I’m not mistaken, @CHA-LEE decreased his spring weight as he decreased slide weight.

I was hoping to get a discussion on slide weight going. Aside from structural integrity, is there such a thing as too light of a slide, from the shooter's perspective? Would it become snappy? I have not seen titanium slides made, is there a reason besides cost and galling for this (doing a boriding or nitriding could fix the latter)? How about an aluminum with steel inserts (bushing, rail, breech face)? I'm also looking at methods for reducing slide weight in a 2011 with cuts. I'm seeing top/side windows along the barrel region, as well as the "gills". Also just milling out from the underside, like in the National Match picture in the extractor channel; can the same be done on the ejector channel side? The benefit of the 1911 platform I suppose is that you have the recoil spring, hammer spring, and firing pin block radius to tune to your slide weight as well. I read Cha-Lee's thread as well; between his experience as a shooter and experiment results, it was pretty neat! I've done my own horrible butcher job on a M&P9 1.0 that I actually really like.

Would anyone with the suppressor ready version be able to measure the distance between the front of the rear sight and the breechface? I was hoping to get one and mill for an SRO yet maintain the rear sight if there’s enough room

I was just thinking that if the chamber in the barrel was long and the extractor had some slop in it for the case to be seated off the breechface of the slide, it would stretch back (after expanding to grip the chamber) and that would locally "neck" or reduce the outer diameter of the case. But from the sounds of it not seating in other 9mm chambers it's expanding/bulging instead.

Is that bulging or is it necking underneath due to excessive headspace? Does it drop into other 9mm chambers? does anyone know of any indications for CZ to make a long(er) slide P-10? If the C and F were the G19/17, then a G34 equivalent?

Would be cool if S&W did a steel frame M&P...or at least a tungsten infused. Would like to see a further undercut up in the beavertail as well as trigger guard as well.