M&P Modification Legality

[aj123]

If I were to do simple modifications such as put a .40 slide assembly on an m&p 9mm, as well as remove the mag safety, would I be in violation of any laws?

Thank you

[hossb7]

Nope. Those are both perfectly legal.

[aj123]

Great thank you

[afteractionreport]

No...i dont think so most gun laws are for buying guns new from an ffl. They have to be sold with certain features but once you buy it you can mod MOSTLY anything on it....its yours to do what u want with it....

[SonofWWIIDI]

Go ahead.

[phase1]

as long as your not doing something illegal like threaded barrels, converting to full auto, add a stock, etc. your good

[nickel plate]

[QUOTE=aj123;13950832]If I were to do simple modifications such as put a .40 slide assembly on an m&p 9mm, as well as remove the mag safety, would I be in violation of any laws?

Thank you[/QUOTE

Just curious-why do you want to put a .40 slide assembly on a 9mm?

[Noonanda]

It legal, but I dont think you should do it. Cant say 100% but I know it applies to other guns that you can go down from 40 to 9mm, but not the other way. Before you do it I would call S&W and ask them what they think as you could possibly damage your frame. but YMMV

[Frito Bandido]

If you're aiming at having the ability to switch calibers, it might be less expensive to sell/trade and just get an M&P 40, then get a 9mm conversion barrel.

This is especially true if you're using APEX parts like the DCAEK or FSS, you wouldn't need to get parts for each slide. If you decide to upgrade your sights, you only need to do it to one slide as well.

[aj123]

[QUOTE=nickel plate;13953339]

If I were to do simple modifications such as put a .40 slide assembly on an m&p 9mm, as well as remove the mag safety, would I be in violation of any laws?

Thank you[/QUOTE

Just curious-why do you want to put a .40 slide assembly on a 9mm?

Just to have the ability to shoot both calibers since they share the same frame.

[aj123]

If you're aiming at having the ability to switch calibers, it might be less expensive to sell/trade and just get an M&P 40, then get a 9mm conversion barrel.

This is especially true if you're using APEX parts like the DCAEK or FSS, you wouldn't need to get parts for each slide. If you decide to upgrade your sights, you only need to do it to one slide as well.

I wish I would have thought about the versatility of the m&p.40 out of the box to begin with. It was a mission to even find the 9mm in the first place so idk if I want to venture finding a whole cal compliant .40

I was looking into the apex trigger kit so that's something that didn't cross my mind thank you.

[aj123]

It legal, but I dont think you should do it. Cant say 100% but I know it applies to other guns that you can go down from 40 to 9mm, but not the other way. Before you do it I would call S&W and ask them what they think as you could possibly damage your frame. but YMMV

From what I've found, the frames and all are exactly the same. One would be able to throw a .40 barrel on the 9mm if it could fit through the barrel hole in the slide (as you can with the .40 to 9 since the .40 is larger).

[aj123]

as long as your not doing something illegal like threaded barrels, converting to full auto, add a stock, etc. your good

Just safety removal and new slide as far as modifications. Upgrades are a lot longer list though (trigger, sights, etc.) thank you