Conversion barrel for 4" M&P 2.0 - .40S&W to .357Sig

O

oworthsr

US Veteran
Joined
Oct 28, 2018
Messages
85
Reaction score
99
Location
Republica de Tejas
Here's a link to the KKM Precision webpage in which KKM claims it has two M&P Compact conversion barrels to make a 4" .40cal S&W into a .357 Sig - one that has suppressor threads and the other a "plain Jane" barrel.

Compact (4.00") | KKM (kkmprecision.com)
M&P Compact 2.0 .357Sig (4.0″ Model) with 1/2×28 Suppressor Threads (4.50 OAL) | KKM (kkmprecision.com)

In response to my emailed query, the manufacturer responded as follows:"...you can literally just swap in that 357sig (both the MPC02 barrel and the suppressor-threaded MPC02T1 barrel) and go shoot. No other modifications or parts are needed to convert your 2.0 compact 4" 40S&W. You will even use the same mags.

This sounds interesting. But I recall my grandfather's commentary on early 1840's Texas settlers: "Pioneers got the land. But they also got the arrows."

So I'm curious...has anyone on this Forum had experience with KKM's barrels? And more particularly these two .40S&W-to-.357Sig conversion barrels?

I'd appreciate your feedback.

johnny-baseball - aka The LoneStarLizzard
 
I have been procrastinating on ordering the .357 Sig barrel for my M&P Pro (5" bbl). Really want to see what kind of velocity I get out of the 5" bbl, but haven't pulled the trigger yet. I am curious with other's experiences also.

Rosewood
 
I can't speak to the .40 to .357 Sig barrel however I have used their .40 to 9mm conversion barrels. KKM Precision makes a fine barrel and the folks there are top shelf in my opinion.
 
Conversion barrel for 4" M&P 2.0 - .40S&W to .357Sig

I enjoy my original M&P 40 & 357 Sig. No need for a barrel. I have the whole gun.


Sent from my iPhone using Tapatalk
 
Last edited:
While I can't comment on KKM, I can vouch for the concept. I bought a RIM Country Manufacturing 357 Sig barrel for my H&K VP40. It dropped right in and functions perfectly using my 40 cal mags. I didn't do anything except swap the barrel.
 
TXbug said:
The KKM .357 Sig barrel will work in the .40 S&W M&P. I have experience with it. If you are worried about a kaboom, there is no need to worry.
Click to expand...

Give them time, someone will chime in with how bad it is to use the sig in the 40 and quote how S&W recommends against it. :D

Rosewood
 
You just did.

It's like conversations with one of my kids. They say, "Dad, can I ask you a question?" I answer, "You just did." They say, "No, no, can I ask you another question?" And I say, "You just did." Finally, they say, "Can I ask you two questions?" "Sure," I respond.
 
AppStFan said:
I can't speak to the .40 to .357 Sig barrel however I have used their .40 to 9mm conversion barrels. KKM Precision makes a fine barrel and the folks there are top shelf in my opinion.
Click to expand...

Same barrel and same impression of the folks in charge.

FWIW,

Paul
 
I have a factory .357 SIG barrel in one of my LE Trade in 1.0 FS M&P .40's and a Lone Wolf 40 to 9mm conversion barrel in another FS 1.0 LE Trade in M&P. I shoot much better with the LW 9mm barrel than any of my other 9mm guns.
 
You could tell him to try underwood 135gr at closer 1430fps or 155gr at 1320fps ammo then figure out why a 357 sig is really wanted as it best with only a 124 or 125gr bullet. leave a lot on the table . If he wants a conversion get a 9mm conversion barrel
 
hardluk1 said:
You could tell him to try underwood 135gr at closer 1430fps or 155gr at 1320fps ammo then figure out why a 357 sig is really wanted as it best with only a 124 or 125gr bullet. leave a lot on the table . If he wants a conversion get a 9mm conversion barrel
Click to expand...

Those 124 or 125 grain 9mm bullets are cheaper than the 135 .400 bullets and easier to find. But I do concur, you can do just about the same thing with a 40 that you can with a .357 sig if you handload or buy boutique ammo.

Sometimes we do things just because we can or because we don't have that one yet. :D

Rosewood
 
Mikey1871, I saw those barrels, too. Unfortunately they are for the Shield, and the manufacturer confirmed to me that (a) those barrels do not fit the Compact 2.0, and (b) the manufacturer had no plans to make conversion barrels for the Compact 2.0.
 
You must log in or register to reply here.

Similar threads

S
M&P 2.0 45 for duty/trigger pull
Replies
18
Views
256
suthrncop66
S
D
S&W M&P 2.0 Compact 4"Recoil Spring
Replies
4
Views
913
hardluk1
H
C
M & P 2.0 Magazine Capacity
Replies
1
Views
348
Saudade
Saudade
JoeDice
M&P 2.0 Subcompact and
Replies
18
Views
1K
hardluk1
H
P
M&P 2.0 .45ACP Non-OR Barrel in OR Pistol?
Replies
2
Views
272
Paul_H
P

Latest posts

Back
Top