Fitting a KKM barrel?

[bigfish]

So I ordered what was suppposed to be a drop in kkm barrel for my m&p9 and its just a little to tight. The I took the slide off to drop the barrel in I had to push kind of hard to get the barrel to go into lock-up. After racking the slide a few times it seems to go all the way into lockup fine now but the gun just doesnt want to run reliably. It tends to stop just alittle before the barrel is all the way up in the lockup position. Can anyone tell me how to fit this barrel to this gun?

[bigfish]

Also I have run about 500 rounds through the barrel thinking it might break in and be ok just the problem is still there

[partyboy424]

Do you have a set of calipers to compare it to your stock barrel? I have 3 KKM barrels and all have needed a break in even though everyone says they don't. However, Mine all broke in with about 200 rounds or so. I did have the problem your describing when I installed a new slide, barrel and extractor. I needed to break in the barrel and file the extractor, but that was a .40. Even though they all needed break in, all of the barrels dropped right in, they just would have a tight lock up, I could literally place the barrel on the slide and angle the slide down and the barrel will drop right in. If it doesn't, something is definitely off.

First things I would try: If you handload, try a new recoil spring with some hotter loads see if it cycles. Try hand cycling the gun slowly, so rack the slide all of the way back and slowly let it forward by hand and see if and where it stops on its own. That way you can figure out if there's a spot that you could hit with a file.

[atbarr]

Get some Dyekem blue or probably just a blue sharpie. Mark you barrel and work the action. That will show you the contact area.

[mcracco]

And if you look closely with an eye loupe you will probably see edges on the barrel that are burred. Stone the burrs down as needed.

If that doesn't work I would be willing to trade you a stock barrel for the KKM.

Edited March 27, 2013 by mcracco

[bigfish]

Well, I stoned the leading edge of the barrel where it locks up with the slide removing about .0015 of an inch and it seems to be much smoother when hand cycling. I ran about 50 rounds through with out any problems. That is better than what it was last Saturday. When measuring the breech to the part of slide that the barrel locks up with on the slide vs the same part on the barrels I had only .001 in clearance with the kkm barrel and .005 with the factory barrel. I have no idea what spec is but .001 seems a little tight. I'll run a couple hundred rounds through this weekend and see what happens.

[pharoh]

if the pistol functions good with the .001 clearance i would prob leave it like that. the tighter lockup will/should help with accuracy. **make sure** to check the barrel and slide after each string of 25-50 rounds to make sure the metal is not peening any wheres.

[Dimon]

Where did you buy a barrel? I did order in January. A few days later received a mail from Kevin, where he wrote that it will take the 4-5 weeks. After 5 weeks, I called and he told me that he needed another 8-10 weeks

[bigfish]

if the pistol functions good with the .001 clearance i would prob leave it like that. the tighter lockup will/should help with accuracy. **make sure** to check the barrel and slide after each string of 25-50 rounds to make sure the metal is not peening any wheres.

That's the problem. It never has functioned properly with the new barrel. It will shoot fine for a few rounds and it chokes. I used a u-die and drop tested the rounds so I doubt that its an ammo issue. I've run at least 500 rounds through it thinking it would break in and start to work ok but it hasn't. I haven't messed with it yet this weekend since its raining but will put some serious rounds through it tomorrow if it's nice out. I do know after a little stoning it locks up much smoother.

[bigfish]

Where did you buy a barrel? I did order in January. A few days later received a mail from Kevin, where he wrote that it will take the 4-5 weeks. After 5 weeks, I called and he told me that he needed another 8-10 weeks

Strait from kkm back in oct. I practiced with it once and shot the last match of the year and until last week when the snow finially melted enough to get out and shoot all I have done with it is dryfire all winter. I had mine with in a week when I ordered it.

[bigfish]

Well, I have run about 250 rounds through it now with now problems. I think I'm just going to call it problem solved. I think we all know that it is like most reliable guns and wont choke until the worse possible time during a stage if it is going to fail so we will see how it is after a few matches.

[mcracco]

So now that it is shooting.....how does it shoot? I assume you spent $200 on a barrel to tighten up your groups.

[Bike Effects]

So now that it is shooting.....how does it shoot? I assume you spent $200 on a barrel to tighten up your groups.

Waiting for an answer on this as well.

[BillR1]

I have two 5" 9mm Pros. My KKM barrel fits in one of them but not the other! The hole in the slide seems smaller or just cut at a different angle...not sure. KKM said to send it back and they would fit it for free, but I decided just to use it in the gun that it fits. I'm thinking S&W cut a few guns slightly different.

[partyboy424]

It should fit, S&W messed up a bunch of slides and you have to torque the barrel up as you put it in and then snap it down into the slide. Doesn't damage the barrel or slide at all, once it's in the gun functions fine.

[bigfish]

Sorry, forgot to post a pick. 15 yards freestyle 147gr precision bullets. Elevation is great except the one flyer. Side to side variation might just be me, after all it was freestyle

[SW4me]

I've been having failure to feed issues with my KKM barrel on my Pro 40. When hand cycling rounds it seems to stick on the 3rd or 4th round out of each magazine.

[partyboy424]

I've been having failure to feed issues with my KKM barrel on my Pro 40. When hand cycling rounds it seems to stick on the 3rd or 4th round out of each magazine.

Extractor related? Is it a new extractor that needs to have the edges broken or a stock one that hasn't been cleaned recently? Almost all feeding issues with M&P's that I've found, are related to extractor issues or weak recoil springs/weak ammo.

[chuck s]

My 5 inch pro grouped only fair ,so I bought a kkm barrel and it was really no different. After 6 thousand rounds, I decided to replace the locking block,and I noticed that the rails were larger(.4 vrs .5 inches) on the new block. The gun shot no different with the original barrel, however, when I tried the kkm barrel it grouped much better, going from 4 or so inches to 2.5 inches at 20 yds.