S&W M&P 40-9

[maxwell0700]

i know you can BUT i want 100% reliability, like if the pistol was 9mm to start off with, i kind of regret buying 40 instead of 9mm.

ive been hearing reliability takes a hit when changing the barrels out...

what do you guys think?

[Jet Setter]

If you are using a stock barrel, then reliability might be an issue. I hear it is better if you use a proper conversion barrel from storm lake or wolf. I use regular 2 port .40 match barrel from SL. I like it. Easy to shoot and accurate. I love my M&P40. Glad I never got the 9. What is it about the 40 that you regret?

[BDP]

I picked up a 40-9 SL barrel. So far no problems except for the first time using it. The first 2 rounds ejected to my face but after that no problems.

[Mike718]

I have problem when I change out the 40 barrel with the 9 factory barrel. I would occasionally have FTE even when using factory 9 magazine.

[Tjfearl]

I have a few hundred through my stock 9mm barrel with 9mm mags, but I only use it for target shooting. I have never have any issues with my full size or compact. If you plan on CCW or HD then I would use the 40 barrel. I only have the stock 9mm barrels to save some cash at the range. If I wanted a 9mm then I would buy a 9mm.

[rsrocket1]

Ditto TJ
I would also have pause for concern if you are involved in a SD situation where the authorities find out that you are registered for a M&P40, but shot with a 9mm bullet. If you really want a 9mm gun for a life or death situation, get a real 9mm gun. Otherwise have fun swapping barrels at the range and enjoy the best of both worlds at a low cost.

I'll bet you can swap for an M&P9 pretty easily, or sell your 40 and buy an M&P9.

[BajaJames83]

I have a few thousand 9mm through a factroy barrel on my 40 gun without any problems, but I use 40 for SD/ HD 9mm just for the range

[maxwell0700]

well i just love to see $11 for the 9mm box and then next to it it says .40, $15 lol, what if i started using steel? what do you guys think of that?

[daybreak]

You're never going to 100% reliability, stock, new, old, converted or not.

[maxwell0700]

well what im trying to mean is that i want as much reliability as i couldve had if i just got a 9mm instead.

[fmunk]

You are not making much sense. I've witnessed nor experienced any problems using a factory 9 mm barrel in a .40 s&w. None.

Too many factors are involved. The internet is the worst kind of sewing club ever. All it takes is one isolated incident and suddenly there's a plague going around. If you want to do it, just do it. If it doesn't work out, whine about it then. Tell you what, sell your 40 and just buy a M&P 22. Even cheaper.

[slid349]

where are you located? I have an almost new full size m&p9 that I might be willing to trade.

[maxwell0700]

Yea? Well my m&p slide is coated in MAGPUL FDE...

I love it but its just want to shoot for less that's all

[9mmepiphany]

I wouldn't do it to a carry gun, but it is just because I have seen enough guns have problems with their stock parts that adding another variable doesn't seem very wise.

I would think the larger concern would be the differing POI between the two cartridges

[chrisf]

I have the 9 and will trade for my beloved .40. Pm if interested.