FPC 9mm Magazine Compatibility Issue

[mmelton]

I've had my 1st gen M&P 9 since 2007. I love it and wouldn't trade it for anything. I've wanted a PCC with compatible mags for a long time but never really liked the Sub2000. I've been wanting the FPC since it came out even though I dislike the stock. I almost ordered one from my LGS this week but ran across a comment (a Reddit thread I think) about how there is an issue with the mags IN THAT the grip/magwell of the FPC is shorter than the pistol. All the mags that come with the carbine have a shim on them. This means the mags can't be used in the pistol w/o pulling the shim off and the mags w/o the shim have a chance of being inserted to far into the magwell of the carbine that the bolt won't close.

I happened to be in the local Bass Pro and checked to see if they had the FPC in stock as well as a pistol. They did and when I explained to the guy what I'd read, he was curious enough to pull both of them down and experiment. Roughly 50% of the time when he had the pistol mag w/o shim in the FPC and racked the bolt, it didn't close unless he pulled on the magazine and fiddled with the bolt at the same time. And, of course, the shimmed magazines wouldn't engage the mag release in the pistol and just fell out.

IMO, the point of having a carbine and a pistol that take the same mags is so you can swap mags as needed in the heat of the moment.

I'm definitely not going to purchase one unless they do a redesign so the FPC takes the standard 17 round mags w/o the need for a shim.

Open to correction or explanations on how/why S&W seems to have goofed on this.

 

[McChemist]

I have a M&P9C 2.0 and a FPC 9mm. I have used the 17 rd pistol mags in the FPC. THOSE WERE Pro-Mag mags, not S&W. I have cycled 15 rnd pistol mag rds through the FPC (without firing). You may have better luck if you try locking back the bolt before inserting a full mag. I have seen a video where ETS mags fail, but can be altered so that they will work. It is a shame that you are having difficulties. The FPC 9 is a blast to shoot and with 9mm prices low, not too big a bite on the wallet. Have you approached S&W about this problem?

Several other items:
1-While all the videos complain about the perceived bolt release button being very tough to use, it is not a release. It is a locking device. To release the the bolt, pull back on ther charging handle and release. That is in the instruction manual. Amazing that none of the gun pundits never read the manual.
2-The dame pundits criticize the 23 rnd mag release lever. Push the right side and the left mag releases. And visa versa for the left mag. The simple hack is to lift up the release lever and the same side mag is released.

 

[mkess]

I have a M&P9C 2.0 and a FPC 9mm. I have used the 17 rd pistol mags in the FPC. THOSE WERE Pro-Mag mags, not S&W. I have cycled 15 rnd pistol mag rds through the FPC (without firing). You may have better luck if you try locking back the bolt before inserting a full mag. I have seen a video where ETS mags fail, but can be altered so that they will work. It is a shame that you are having difficulties. The FPC 9 is a blast to shoot and with 9mm prices low, not too big a bite on the wallet. Have you approached S&W about this problem?

Several other items:
1-While all the videos complain about the perceived bolt release button being very tough to use, it is not a release. It is a locking device. To release the the bolt, pull back on ther charging handle and release. That is in the instruction manual. Amazing that none of the gun pundits never read the manual.
2-The dame pundits criticize the 23 rnd mag release lever. Push the right side and the left mag releases. And visa versa for the left mag. The simple hack is to lift up the release lever and the same side mag is released.

Crazy that you mentioned the bolt catch. My LGS was having a hard time getting it to release and even said that it's a common complaint. I get home and start reading the manual and came to the same conclusion as you.

 

[JRD]

The FPC was deliberately designed with an M&P 2.0 Compact sized frame for compatibility with the majority of M&P 9mm factory magazines. You can use the 23 rounders, 17 rounders from a full sized pistol, and the 15 rounders from the 2.0 Compact. The theory of using the same magazines between the pistol and carbine was indeed what S&W had in mind.
However, when using the 17 and 23 round mags there is a gap left between the grip and buttplate. S&W includes those spacers as an ergonomic feature for those who want pinkie finger support. They are not needed to properly locate the magazine. See the owners manual, page 40 in bold "Grip adapter -not required for proper function in the M&P®FPC®".

https://www.smith-wesson.com/customer-service/owners-manuals

In your case, when you were at Bass Pro, were you holding in the mag catch button while you attempted to over insert the magazines? If you just insert the mag normally, the mag catch should engage and prevent the magazine from overtraveling far enough to touch the bolt, even without the pinkie finger spacer.

I shoot my FPC with full size mags without the spacer and have no issues. I can then insert the mags directly into a full sized pistol too.
Don't pay too much attention to the Reddit experts. Most probably haven't read the manual or found out what S&W's actual design intent was.

Also, the FPC has a bolt catch (not bolt release) which is meant for locking the bolt open only. To close the bolt, rack and release the charging slide. As McChemist points out, that's what the manual instructs. Why not push the bolt catch finger tabs to release the bolt? Look at the massive recoil spring that's powering the bolt. You're trying to overcome that spring to release the bolt so just learn the manual of arms to rack and release the charging slide.

ETS magazines being plastic have much thicker lips than the factory sheet metal magazines. They require more clearance around the lips than factory metal magazines and apparently the FPC underside of the bolt is different that a pistol slide. Just use factory mags. They are more durable anyway.

I've grown quite fond of my FPC's and shoot them a lot. Multiple friends at my gun club have bought their own after trying mine. I find them quite handy, fun to shoot, and the manual or arms has gotten to be second nature.

 

[zaitcev]

This means the mags can't be used in the pistol w/o pulling the shim off and the mags w/o the shim have a chance of being inserted to far into the magwell of the carbine that the bolt won't close.
. . .
Roughly 50% of the time when he had the pistol mag w/o shim in the FPC and racked the bolt, it didn't close unless he pulled on the magazine and fiddled with the bolt at the same time.

Magazine overtravels on the ejector in a PCC. So just insert it until it clicks, then tug on it to make sure it's seated. That's all there's to it.

 

[JRD]

"Magazine overtravels on the ejector in a PCC."
Not on all PCC's. The FPC doesn't use the ejector for mag location.
"So just insert it until it clicks, then tug on it to make sure it's seated. That's all there's to it."
Yup. Agreed.

 

[Quicksteel57]

I was using the full size pistol mags for my FPC today and a problem I encountered was the bolt locking back during firing.
This happened several times with both 115gn practice and 124gn defense ammo. It never has happened before when using the FPC mags, but started today after using the pistol mags. It happens with both kind of mag now. Any Ideas on why?

 

[McChemist]

The FPC was deliberately designed with an M&P 2.0 Compact sized frame for compatibility with the majority of M&P 9mm factory magazines. You can use the 23 rounders, 17 rounders from a full sized pistol, and the 15 rounders from the 2.0 Compact. The theory of using the same magazines between the pistol and carbine was indeed what S&W had in mind.
However, when using the 17 and 23 round mags there is a gap left between the grip and buttplate. S&W includes those spacers as an ergonomic feature for those who want pinkie finger support. They are not needed to properly locate the magazine. See the owners manual, page 40 in bold "Grip adapter -not required for proper function in the M&P®FPC®".
https://www.smith-wesson.com/customer-service/owners-manuals

 

[jack zeller]

The FPC was deliberately designed with an M&P 2.0 Compact sized frame for compatibility with the majority of M&P 9mm factory magazines. You can use the 23 rounders, 17 rounders from a full sized pistol, and the 15 rounders from the 2.0 Compact. The theory of using the same magazines between the pistol and carbine was indeed what S&W had in mind.
However, when using the 17 and 23 round mags there is a gap left between the grip and buttplate. S&W includes those spacers as an ergonomic feature for those who want pinkie finger support. They are not needed to properly locate the magazine. See the owners manual, page 40 in bold "Grip adapter -not required for proper function in the M&P®FPC®".

https://www.smith-wesson.com/customer-service/owners-manuals

In your case, when you were at Bass Pro, were you holding in the mag catch button while you attempted to over insert the magazines? If you just insert the mag normally, the mag catch should engage and prevent the magazine from overtraveling far enough to touch the bolt, even without the pinkie finger spacer.

I shoot my FPC with full size mags without the spacer and have no issues. I can then insert the mags directly into a full sized pistol too.
Don't pay too much attention to the Reddit experts. Most probably haven't read the manual or found out what S&W's actual design intent was.

Also, the FPC has a bolt catch (not bolt release) which is meant for locking the bolt open only. To close the bolt, rack and release the charging slide. As McChemist points out, that's what the manual instructs. Why not push the bolt catch finger tabs to release the bolt? Look at the massive recoil spring that's powering the bolt. You're trying to overcome that spring to release the bolt so just learn the manual of arms to rack and release the charging slide.

ETS magazines being plastic have much thicker lips than the factory sheet metal magazines. They require more clearance around the lips than factory metal magazines and apparently the FPC underside of the bolt is different that a pistol slide. Just use factory mags. They are more durable anyway.

I've grown quite fond of my FPC's and shoot them a lot. Multiple friends at my gun club have bought their own after trying mine. I find them quite handy, fun to shoot, and the manual or arms has gotten to be second nature.

 

[GUNMAN40]

I have shot mine with the factory magazines, ProMag 17 rounders and ProMag 33 rounders without any issues.

 

[zaitcev]

I was using the full size pistol mags for my FPC today and a problem I encountered was the bolt locking back during firing.
This happened several times with both 115gn practice and 124gn defense ammo. It never has happened before when using the FPC mags, but started today after using the pistol mags. It happens with both kind of mag now. Any Ideas on why?

How many rounds remain?
If only 1, then the root cause is obvious.
If more than 1, it's not so obvious. Bullets may be touching the pawl, or the recoil activates it.

 

[McChemist]

The FPC was deliberately designed with an M&P 2.0 Compact sized frame for compatibility with the majority of M&P 9mm factory magazines. You can use the 23 rounders, 17 rounders from a full sized pistol, and the 15 rounders from the 2.0 Compact. The theory of using the same magazines between the pistol and carbine was indeed what S&W had in mind.
However, when using the 17 and 23 round mags there is a gap left between the grip and buttplate. S&W includes those spacers as an ergonomic feature for those who want pinkie finger support. They are not needed to properly locate the magazine. See the owners manual, page 40 in bold "Grip adapter -not required for proper function in the M&P®FPC®".

https://www.smith-wesson.com/customer-service/owners-manuals

In your case, when you were at Bass Pro, were you holding in the mag catch button while you attempted to over insert the magazines? If you just insert the mag normally, the mag catch should engage and prevent the magazine from overtraveling far enough to touch the bolt, even without the pinkie finger spacer.

I shoot my FPC with full size mags without the spacer and have no issues. I can then insert the mags directly into a full sized pistol too.
Don't pay too much attention to the Reddit experts. Most probably haven't read the manual or found out what S&W's actual design intent was.

Also, the FPC has a bolt catch (not bolt release) which is meant for locking the bolt open only. To close the bolt, rack and release the charging slide. As McChemist points out, that's what the manual instructs. Why not push the bolt catch finger tabs to release the bolt? Look at the massive recoil spring that's powering the bolt. You're trying to overcome that spring to release the bolt so just learn the manual of arms to rack and release the charging slide.

ETS magazines being plastic have much thicker lips than the factory sheet metal magazines. They require more clearance around the lips than factory metal magazines and apparently the FPC underside of the bolt is different that a pistol slide. Just use factory mags. They are more durable anyway.

I've grown quite fond of my FPC's and shoot them a lot. Multiple friends at my gun club have bought their own after trying mine. I find them quite handy, fun to shoot, and the manual or arms has gotten to be second nature.

The FPC bolt is very differently, considering that it is hammer-fired and the pistols are striker-fired.

 

[marvin02]

The FPC bolt is very differently, considering that it is hammer-fired and the pistols are striker-fired.

The FPC and the double stack M&P pistols do use the same magazines even though the rifle is hammer fired and the pistols are striker fired. The FPC was designed that way.

I've shot steel challenge matches with my FPC and M&P 2.0 and used the same mags for both. Mags with a 15 round capacity or larger work in the FPC. The 23 round mags that come with the FPC works fine in all of my M&P double stack pistols.

The issue the the OP was/is having is not a common one. The mags are interchangeable.

* Some 10 round mags designed for restricted capacity states will work in the FPC.

*Edit "the FPC underside of the bolt is different that a pistol slide "

This is true. Aftermarket mags with thicker lips (usually plastic) that work in the handguns don't work in the FPC. I have used non S&W metal mags that work fine.

 

[McChemist]

The FPC and the double stack M&P pistols do use the same magazines even though the rifle is hammer fired and the pistols are striker fired. The FPC was designed that way.

I've shot steel challenge matches with my FPC and M&P 2.0 and used the same mags for both. Mags with a 15 round capacity or larger work in the FPC. The 23 round mags that come with the FPC works fine in all of my M&P double stack pistols.

The issue the the OP was/is having is not a common one. The mags are interchangeable.

* Some 10 round mags designed for restricted capacity states will work in the FPC.

*Edit "the FPC underside of the bolt is different that a pistol slide "

This is true. Aftermarket mags with thicker lips (usually plastic) that work in the handguns don't work in the FPC. I have used non S&W metal mags that work fine.

I have the FPC & M&P9C. No problems with S&W & Pro-Mag magazines. Striker v. hammer shouldn't matter until it does.