Art Yeo

Nice bullets but nearly as expensive as jacketed. I only use them for big bore revolver rounds and for my .45 70. For pistols their are better choices. Pat Me, too. I tried their 44mag and 500SW --- they are pretty accurate but pricey; certainly not a bulk bullet.

That's a nice link. Thanks!

Thanks. What's the twist-rate of your bbl?

For competition pistol reloaders, Montana Gold and Zero Bullets are smaller bullet companies that produce decent bulllets. Their quality and pricing allow them to compete with big names like Hornady, Speer, Barnes and the like. In the rifle world, are there such companies you favor for the 223rem and 308win calibers? I'm looking to buy jacketed bullets in bulk. But, if you know of any equivalent to the Bear Creek lead bullet producer for rifle, I'd be interested, too.

I have not done a lot of testing on 147gr yet. Others (like Julie Golob) felt that the M&P9 performs more consistently at longer distances than lighter bullets. I just received my case of 147gr and will be testing them next.

Go to page 3 of this thread.

As for why S&W has chosen the 1:18.75" twist, it was due to their success with .38sp revolvers implementations. The question we need to ask is this: since the .38sp revolvers shoot bullets from 110gr - 200gr accurately with this twist-rate, why do we need any other twist-rates? New findings with Gen2 Barrel and How to make 9mm Accurate Pertaining to the 9mm Luger cartridge, I have been digging around and testing loads myself. It turns out that the 9mm Luger favors higher loads (i.e. with higher pressure). In the mid-1980's, this has been consistently shown by the US Army Marksmanship Units testings and their use of these heavy loads for national bullseye competition. Some of these can be found here (Article: The 9mm can be Accurate). Most of their loads made their bullets fly at 1200+ fps and they are getting 2" groups and better at 50 yards. I think Sin-ster and Trident have also confirmed (in the earlier pages of this thread) that the higher they push the power factor, the tighter their holes grouped. I believe this is contrary to the 45ACP cartridge, which is considered a low pressure cartridge. Obviously, higher pressure in the 9mm would entail larger recoil and slower follow-ups, which the bullseye competitors don't really care. Fast shooting games (like IDPA, IPSC, etc), however, may need to compromise and balance between good splits and accuracy. Among the various tests I have done, here's one particular load that may be interesting to you all: Ambient Tempt: 55 deg F Powder: Win231 Charge: 4.7gr Gun: M&P9 FS + Gen2 bbl Bullet: MG 124gr FMJ OAL: 1.1440" +/- 0.0005" Distance: 25yards Group: 2.5" I'll re-test this to see if it was a fluke or it is reproducible. As you can see, accuracy which you guys wanted is achievable with a production M&P9 that used to be a failure with a Gen1 bbl is now scaling the wall with leaps and bounds using the Gen2 bbl and the proper load. Disclaimers: I am not liable if your gun, hands or face is blown off to space. Use the loads and the partial magazine article at your own risks. Win231 is reported to be sensitive to temperature and atmospheric pressure. So, do not trust your loads if you are loading at low altitude and competing at higher altitude or vice-versa. My next step is to fine tune around this locus and see how the rest of my 9mm guns behave. I have a deep feeling that the Beretta 92A1 will perform better with an even hotter load based on the US Army's data. So far, I am not seeing flattened primers ... yet. PS: Having said all these, I must underscore the fact that the 9mm Luger cartridge is one of the most sensitive cartridges I have ever dealt with in terms of trying to achieve accuracy. It's like getting the stars to align before you shoot and if someone sneezes after the discharge, you may miss the bullseye. Compared to 9mm, the 45ACP cartridge was a walk in the park.

I tried Nu-Finish last weekend and it had the same effect as Dillon. I am a new convert now.

Yup, it is.

Yes, Apex says many things but so far, I have not seen anything released to the market that fixes the accuracy issue with M&P9 yet. I am still waiting..

KKM bbl difference I just spoke to KKM and what I have gathered so far made sense: External dimensions: they said they have increased the external dimensions to improve the lock up tightness when the barrel is in battery. Internal surfaces: they are significantly more polished. You can verify this by looking into a KKM barrel and compare it to production ones. Rifiling: they claimed that button rifiling is more consistent through the length of the barrel vs the broach rifling method. Button rifling also cost more in terns of time and resources and cannot be effectively used in mass production.

It sounded like you are saying premature unlocking is progressively worse for every subsequent shot. That's why there is vertical stringing. Why would each subsequent shot unlock with an ever increasing/decreasing elevation? Wouldn't one expect it to prematurely unlock at about the same instance? It's still not making sense to me. In my experience with the Gen1 S&W bbl, even though my POA is about the same, I am seeing shots hitting high and then low and they oscillate high/low on alternate shots. But, there's no fixed windage either; i.e. along the horizontal axis, I do not see any patterns. I doubt if there's any compelling reason to send in a plastic gun for gunsmith fit. Again, I want to bring out the fact that there are many competing products out there that certainly do not need a gunsmith to fit the barrel nor need me to buy a match barrel to shoot 3" or better at 25 yards.

Why would vertical stringing be the symptom for premature unlocking? Could you elaborate on it a little, please? My question is why are the competing guns from other brands behaving just fine with any of the ammo? Thanks!

That's the same price as Dillon's Rapid Polish.

Google "premature unlocking M&P 9" and you will see them all. I am curious what you think is the cause of the accuracy?

I think we're forgetting that with the same type of hand-loaded ammo, quite a few of the other competing pistols performed about the same --- very good. Why is there so much need to tweak every single parameter just to make the M&P9 perform close to par? I don't think it is the ammo (bullet, powder, OAL, etc) because I 'd bet that all of your ammo will perform fine on other competing pistols at 25 yards. I'm going to do some more testings in comparison to my other pistols at 25 yards just so we have a base to discuss. Since I no longer have the S&W Gen1 bbl, it'll be with the Gen2 bbl.

******************************* *** 2 More conjectures *** ******************************* Weight of bbl: I have recently measured the weights of the gen2 bbl vs the KKM bbl and they are the same on my postal electronic weighing machine. I no longer have the gen1 S&W bbl. If anyone still has it, could you kindly weigh it and let us know the weight, please? So, here's the theory ... Heavier bbl means higher inertia and higher inertia takes longer to move it; thus, reducing the premature unlocking issue. Lowering the discharge load: if increasing the recoil spring would slow down the premature unlocking of the bbl, wouldn't reducing the discharge load of the ammo do the same to attack this problem? Anyone tried that?

17# Thanks!

Well, it appears that some believe the premature unlocking of the barrel could be caused by a weaker than necessary recoil spring and replacing it with a Wolfe 20lb spring may solve the issue. So, here is another article that supported the theory that a heavier recoil spring can extend the length of time before the unlocking of the barrel. I know that this article is talking about the 40SW cartridge but look for the phrase "heavier than factory tension recoil spring" in that article and you'll see that it is talking about a similar issue about premature unlocking except for the 40SW case, it was safety related. Assuming swapping in a 20lb recoil spring may tune the accuracy even further, I guess the downside is that it will increase the split time for follow-up shots, wouldn't it? PS: Does anyone know what the strength of the factory recoil spring?

If understand you correctly, you are unscrewing the 2 screws underneath the priming assembly and swapping it out? Correct. Takes all of two minutes. Unscrewing them is easy, putting it back and aligning it takes more than 2-3 mins in itself. Then, some QC check by looking through the primer magazine from the top (vertically down) and lifting the platform to ensure the primer seat arrives directly underneath the primer mag. So, in my experience, to manually switch out the primer size support, it takes slightly more than 5-6 mins. Yes, a little patience can help. -- Art Y.

Wow, now that's a deal but they are mainly in CA and one store in MT only.

If understand you correctly, you are unscrewing the 2 screws underneath the priming assembly and swapping it out?

I gave up on this pursuit quite a long time ago and I certainly will not pay more than $400 for it. I have shelved this idea up for the 2nd half of next year. Incidentally, for retailers that are selling to LEO/Military/1st-Responders, they have allocation beyond your wildest dream. But, none of us civilians qualify to buy those.

So, it seemed, conjectured and some proven it for themselves. I have not tried it myself but may, one of these days. Incidentally, I have gone back to the range today to try the KKM barrel at 25 yards and compared it to my Les Baer Premier II 1911 45ACP. The performance of the KKM barrel is glaringly eye-popping when you stretch the shooting distance to 25 yards. At shorter distances, the KKM barrel looks and performed close to the Gen2 S&W barrel but once you increase the distance to 25 yards, its abilities are astounding. I had to stretch myself in my bulls-eye shooting techniques as well. Before I post the pics, I'll have to go to the range just one more time to shoot the 25 yards target with the Gen2 S&W barrel so as to convince myself whether I was right or wrong with the original postulation. I didn't have enough time to do it today.

Well, it appears that some believe the premature unlocking of the barrel could be caused by a weaker than necessary recoil spring and replacing it with a Wolfe 20lb spring may solve the issue.