Got my 9mm barrel today for my 40c

[125JHP]

Midway still has some in stock for those interested.

I have read the posts saying they ordered a S&W factory 9mm replacement barrel for their 40c and it converted & worked just fine. I also have read other posts that say you need a conversion type barrel from Storm Lake for it to be reliable, but I have never seen any post where the reasons or the differences between a factory and a conversion barrel have been detailed.

So I ordered the factory 9mm at half the cost. The first thing I did when I got it was to measure several areas with a caliper.

So far I can find one only one place externally where the dimensions are significantly different between the two and it isn't by much. That is in the width of the top hood (where the hole to view the loaded case is). On the .40 it measures .426" and on the 9mm it is .396" for a difference of .03" Is this critical in any way?

Also, on the very bottom of the front barrel lug, where there is a radius for the slide stop pin, it is slightly narrower than the one on the 40 barrel.(.326 vs .330 which I don't think is anything to be concerned about).

Every other dim between the two barrels has been the same.

Since I'm still curious, does anyone know the real differences between a regular barrel and a 'conversion' barrel or is it just marketing hype?

I will take this out in the desert one day soon when my 9mm mags arrive to see how she runs.

 

[S&WOkie]

Thanks for the info.

I have been waiting for them to re-stock. I just ordered one for my .357 Sig compact.

I have a .40 cal. barrel for it also, so now I will have a three caliber gun.

 

[patbelly]

I have a regular SW factory 9mm barrel for my 40 compact and it has been flawless. I don't know if there are any differences btwn factory and conversion barrels, but would guess that the conversion barrels were selling before someone realized that the factory barrels would work just fine if not better. Just a guess.

 

[1sailor]

I don't have a compact but i do have a factory 9mm barrel for my full size. So far I have fired more than 1200 rounds of 9mm through it. I have found that with WWB and Federal I have zero problems when coupled with a 9mm magazine. Using the Remington green and white box I have about one failure to fully eject about 1 in a hundred. My son and I put 250 rounds of Federal 9mm through the gun yesterday and had zero problems. I find it to be just fine for target practice and it saves me a lot of money.

 

[MichiganScott]

Using the Remington green and white box I have about one failure to fully eject about 1 in a hundred.

Not the first report of Remington ammo having problems of late. I have a couple of boxes of older Remington 9mm ammo and a case of older .22 LR that function fine. The problems appear to have become worse since Cerberus bought them and with their cheaper lines of ammo.

Really too bad to see an American company slowly lose its reputation for quality.

 

[SurgicalShark]

I have yet to have any problems with the S&W drop in 357 barrel or the 9mm barrel. Both work flawlessly in my FS 40. I'm going to order one in 9mm for my pro soon.

M&P 40/357/9mm, M&P 40 PRO, M&P 22

 

[125JHP]

Thanks for all of your positive reports, it adds confidence to the practice of changing barrels in the M&P. I hope the difference in the hood width is not something to be concerned about. I know in the 3rd gen series they narrowed the width of it in later years to where the barrels were not interchangeable and hope that is not the case here.

Could any of you with calipers or micrometers, measure the width (L to R across the top next to the chamber block) of your barrel hoods? It would be interesting to see if the difference I have is typical between calibers or may be a general production change in newer guns. My .40 measures .427" and the 9mm is .397"

I also have started having extraction failures in a few different guns that never gave me a problem before and it is usually with Remington cases. I wrote it off as being reloaded too many times but there may be some other cause perhaps related to the brass design. I may section a few cases and look at the rim profile under the microscope. I did that with some 45 and there is a variation of the rim & groove profile between manufacturers to where I can see why some may not catch the extractor hook all that well.

Thanks

 

[M_E_]

For those of you looking for the free lunch, how does the thing shoot? With a variable lock up on the rear of the barrel, you may get groups of 2 feet at 10 yards if the barrel slips from side to side. Shot a Glock 26 with a 27 slide marked 26. we found a 27 barrel that fit perfectly t the range!! The poor owner couldn't put a hole in a 4X4 foot target at 7 yards because the rear of the slide had even more slop on the breach face. It really IS NOT a safe thing to mis match parts like that. We spend hundreds of hours at the rifle shop to get a perfect lock up on our guns.

 

[patbelly]

For those of you looking for the free lunch, how does the thing shoot?

Shoots great. Lockup is tight. All rounds within a fist size hole at 7 yards. That's about the same as any handgun I own/shoot.

Phoenix, AZ 74-77, Alhambra HS.

 

[1sailor]

At a local(ish) range with my 9mm barrel I put my pistol up against a Beretta 92fs, a Beretta PX4 and 2 CZ's. I outshot or performed as well as any of them. Offhand at 50ft I will easily keep a full magazine of 9mm's inside a 3" circle with about half of those producing a quarter sized hole. Not a target pistol but certainly more than good. As far as safety goes I can only say that I have fired hundreds of rounds as have many others with no safety issues at all I am aware of.

 

[1sailor]

I just want to add that I agree with M E that mixing up parts is not always safe and should always be done with extreme caution. However, this is a case where the swap has been performed by many shooters having fired thousands of rounds through multiple guns and has not shown itself to present any dangerous effects. Careful examination after field stripping has not shown any ill effects. And to the contrary has shown itself to be a reasonably priced alteration that can save the shooter at least 30% or more in savings for training ammo. And, at least with my own pistol, has demonstrated accuracy at least on a par with the original caliber and equal to any other 9mm's I have tested it against.

 

[1sailor]

The target below was fired using a factory 9mm barrel installed in my M&P40. It was a used target that was full of holes so we stuck on a 3", a 2", and a 1" inch orange dot to cover most of the holes. The first 6 shots were fired using a combat hold on the target and produced the 6 holes in the 3" orange dot (at a measured 50ft). I really can't get good accuracy with a combat hold. I then fired the remaining 9 rounds in the magazine using a 6:00 o'clock hold on the middle of the black diamond in the big dot. That produced the lower group. With the exception of the one round touching the black on the 2" dot everything went into the ragged hole you see. While not exactly centered that's not too bad for 8 rounds. While that group is not typical it is not too far off from what I have come to expect when taking my time with a 6:00 o'clock hold.

 

[S&WOkie]

Are you guys using you .40 cal. magazines, or 9mm mags.?

I have heard that the .40 cal. mags work until the last round.

Thanks

 

[SurgicalShark]

I use 9mm magazines when I use the S&W drop in barrel in M&P40. I also use the S&W 357Auto (Sig) barrel. The gun was designed to do this according to the technicians at Smith & Wesson. They did state that the use of aftermarket barrels is contra-indicated and do not suggest using them.

M&P 40/357/9mm, M&P 40 PRO, M&P 22

 

[S&WOkie]

I use 9mm magazines when I use the S&W drop in barrel in M&P40. I also use the S&W 357Auto (Sig) barrel. The gun was designed to do this according to the technicians at Smith & Wesson. They did state that the use of aftermarket barrels is contra-indicated and do not suggest using them.

M&P 40/357/9mm, M&P 40 PRO, M&P 22

Thanks for the input.

My M&PC.357 Sig came new with an additional factory .40 S&W barrel, night sights, and three mags.

It was a LE special order that was never issued.

 

[125JHP]

Botach has 9mm 17 rd S&W magazines for $23 + free shipping - got mine in the mail today

 

[S&WOkie]

Botach has 9mm 17 rd S&W magazines for $23 + free shipping - got mine in the mail today

I get all of my M&P and Glock mags from Botach.

They have been good to deal with.

I use the full size M&P mags in my Compact with the X-Grips. Great set up!

 

[125JHP]

Well, I took the 9mm barrel out to the desert along with 6 brands of 115gr ammo and some 124 & 147 gr reloads. All together I only fired about 75 rounds, but had NO functional issues and accuracy at 10 yds was on par with my other guns and my ability, so no problems there either. I had one group of 10 round in 2 1/4" covering the 1" dot on the 9" paper plate I use for targets.
I even tried 9mm in the 40 magazine and they all fed fine except for the last round - the slide locked back as if the mag was empty. Slingshot the slide and it fed into the pipe and was away. So for range use, I am happy so far that i didn't pay 2x the price I had to. Also there wasn't any play or wiggle at the hood when locked up. That is not to say there couldn't be a little alignment skew going on as the parts cycle back into battery but I don't see it on paper yet.

 

[msg73]

Thanks for sharing. I have a M&P40FS and just got a factory 9L barrel to try out. In measuring both barrels, I also agree with your findings that all of the measurements were virtually the same at multiple points except for the "barrel hood". The 40FS is .423" wide and the 9L is .397" wide, which are comparable to your dimensions. Lining up the barrels, they look identical with the exception that the 40 ramp is a bit longer (and the 9L barrel itself is longer). The lockup is nice and tight as well. I also noticed that the end of the barrels (last 1/2" or so) are flared a bit. Since I'm using a 9L barren in a FS slide, there's more space between the barrel and the slide opening it goes through. I don't think it will be an issue as it fairly secure with the lockup. Also, they are not like 1911 barrel bushings and don't think the barrel/slide fit matters....we'll see. Got some 9mm mags and am going to try to get to the range tomorrow. Wish me luck.

BTW: I got the 9L because I may get it threaded for a comp or ported if it functions properly and has decent groups. Any idea how much threading or porting would cost?

 

[125JHP]

msg73 - Thanks for those measurements. Also glad you mentioned your longer barrel, please report back your experience.

I too have wondered if that enlarged end makes any difference and if the barrel will cycle reliably and be reasonably accurate when fitted in a shorter slide. I haven't figured out its purpose and assumed it had something to do with final lockup. I will be interested in seeing if accuracy is affected, otherwise... what is it there for?

I am on the lookout for a compact size 357 sig barrel but it seems only the factory FS are available (the aftermarket ones are too rich for my pocket). If your longer barrel works, I may try a FS 357 in my compact.