Magazine Blocks to reduce capacity. Are they legal in MA?

the factory long 10 round mags for the M&P 15/22 come apart easily to upgrade back to 30 rounds.

I could certainly set up a Glock mag with a magpul blocker to be more difficult to disassemble than the factory S&W 10 round mag.

What's the threshold. That's the question. And the only real answer is that nobody really knows. So what is your risk tolerance??

I carry old U notch non-drop free mags in my GEN 5 Glock 19 for 4 reasons.

1) With a Wolfe spring and updated follower it runs FLAWLESSLY.
2) I don't carry a spare mag, so non-drop free is better for me. Especially as a Left handed person.
3) With the new follower it will NOT lock the slide back on empty. Since I'm not carrying a spare, why telegraph if the gun is empty.
4) there is absolutely positively ZERO doubt that this mag is 100% LEGAL.
 
You would think that DAs would have better things to do with their time however I absolutely have no doubt that some DAs would go after you in this state.

My friend is a long time LEO. One of the good ones. We have discussed this on several times. He says that if he gets you for high cap magazines you have other problems and he is just using that as an add on.
An "add on" that happens to be one felony count for each magazine possessed. One guy on another forum had a UC-Berkeley campus police "friend" who told him that it no big deal to carry a pocketknife on campus, then busted him for it. I don't trust cops...period. Do so at your own risk!
 
The best way to block a mag is to use a stainless steel pop rivet to block the follower and then use a TIG torch with a .045 Tungsten and some .035 309L filler to weld the head of the rivet to the mag body. It's quick and easy, can't be reversed without grinding and drilling, and it's possible to reverse by just cutting it out with a spot weld cutter and welding up the hole. Of course, this requires you being a decent TIG welder with a machine that runs smooth on low amperage as it is a very small weld on very thin material. On an aluminum mag, u can use an aluminum rivet and the appropriate filler.

If the block is welded to the mag body, there is no question about it being permanent, as it literally becomes part of the magazine body. It can't be returned to high cap status by simple disassembly, or chipping out the epoxy, or any other f***ery that could be done by a lawyer or "a firearms expert" in a court room. Nobody is going to whip out a welder, a drill, and a grinder in a court room and try to tell a judge that it can be easily converted back to high cap. If you want to be extra sure do it on both the front and back of the mag and grind the weld flush and refinish the mag body so the average idiot can't tell it's been modified.
 
Aren't these blocks bad for the mags?

If they prevent the spring from compressing all the way, isn't that bad?

I remember reading somewhere (maybe here?) That as long as the maga are fully loaded and the spring is fully compressed, they will be fine, but you don't want to have a mag half full for a long period of time.
 
If a LEO finds you with anything that looks like a high cap he's arresting you. The old 'Tell it to the Judge applies here'.

Lol, Casually? You're assuming said LEO gives a shit, and that's hardly even consistent. An awful lot of them, don't, if a person is otherwise licensed properly.

Now, if you're actually being investigated for something, or served process and your shit is confiscated, wholly different ballgame.
 
Aren't these blocks bad for the mags?

If they prevent the spring from compressing all the way, isn't that bad?

I remember reading somewhere (maybe here?) That as long as the maga are fully loaded and the spring is fully compressed, they will be fine, but you don't want to have a mag half full for a long period of time.
Can't say as I could imagine why. Springs fail for two reasons - plastic deformation, and fatigue. Properly designed, modern magazine springs should remain in their elastic region through their entire range of travel; if there's (basically) no creep at full compression there shouldn't be any at half. Fatigue is a function of cycles: empty > full > empty; no amount of sitting in storage increases cycle count.

Maybe if you drop a partial mag it's possible for the whole thing to hammer itself apart on the rebound? That sounds like such a stretch as to be not worth considering...except for maybe the P320
 
Aren't these blocks bad for the mags?

If they prevent the spring from compressing all the way, isn't that bad?

I remember reading somewhere (maybe here?) That as long as the maga are fully loaded and the spring is fully compressed, they will be fine, but you don't want to have a mag half full for a long period of time.
This nostrum doesn't make sense like @Mesatchornug indicates. Look at cripplemags as an example. Some cripples like CZ basically have a full length mag spring and dimples that impede the follower accepting more than 10 rounds. Cripplemags are stupid, but these mags aren't any worse than other cripples, despite the spring only ever being pressed like 50 or 60% of the way down.
 
AW violation:

Dude was lucky the department armorer didn't monkey with the sear to get the weapon to fire fully automatically. ATF would get involved and he would be facing a U.S. attorney as a prosecutor and 10 years in federal prison.
 
Aren't these blocks bad for the mags?

If they prevent the spring from compressing all the way, isn't that bad?

I remember reading somewhere (maybe here?) That as long as the maga are fully loaded and the spring is fully compressed, they will be fine, but you don't want to have a mag half full for a long period of time.

Nope, half full for a long period of time is totally fine. Two ways to wear a magazine spring.
1. Cycles of compression and decompression
2. Time spent near, at, or beyond the elastic limit of the spring

Some magazine springs are near their elastic limit when fully loaded, others not as much. But storing a magazine half full or less is extremely safe from a magazine spring life standpoint.
 
Lol, Casually? You're assuming said LEO gives a shit, and that's hardly even consistent. An awful lot of them, don't, if a person is otherwise licensed properly.

Now, if you're actually being investigated for something, or served process and your shit is confiscated, wholly different ballgame.
Well if they're checking your magazines they are already looking at you for something.
 
Back to the original post: Go ahead and install your magwell. Trim the plastic mag bases to be flush with the mag body and at this point they will seat with the magwell. Then epoxy the baseplate of your choice such as the Henning, Taran Tactical, or the Springer Precision, depending on the weight and material of your preference (or make your own!). Don't screw around with a block when you can use the spring as it was intended and simply remake the floorplate to fit with the magwell. Putting junk inside a mag body is asking for some tiny bits of the block to come off and snag the spring at an inopportune moment. Your issue is not the mags, it's the fact that you want a magwell. Some people just do the first step of just trimming the factory "plate" to be flush with the mag body and leave it at that.

Also, I believe Carver Custom makes what you want.
I think this works with their magwell. Their site is probably worth a browse for you.
 
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Lol, Casually? You're assuming said LEO gives a shit, and that's hardly even consistent. An awful lot of them, don't, if a person is otherwise licensed properly.

Now, if you're actually being investigated for something, or served process and your shit is confiscated, wholly different ballgame.

If a LEO is inspecting your mags to see how many rounds they hold, its a safe bet you are already cuffed and in the back seat of a police car. i.e. You are getting arrested anyway.
 
If the ADA can knock out the block with a ball-peen hammer and load the magazine to its full (over 10 rounds) capacity in front of gullible jurors, he/she could very well secure a conviction.
3D print the block with a small vial of nitroglycerine concealed within.
Tell the DA to peen away.
 
I'm no gunsmith but I am pretty sure anyone could drill them out and the mag would load to full capacity and work fine.
Old thread, but wanted to respond. Canik magazines (that I have seen) have a fairly small, ovoid/oval dimple that could be readily drilled or dremelled out, returning it to free state capacity. There is no horizontal serration, as with some S&W mags that I have seen that have long horizontal indents on both broad sides of the magazine, and a serrated line thru the rest of the circumference such that it will split in two if the indents are dremelled out. A reason to not buy S&W, or at least relevant offerings of theirs. I think there is another manufacturer that does the same, maybe also in the Mass/Conn area, but I forget.
 
Old thread, but wanted to respond. Canik magazines (that I have seen) have a fairly small, ovoid/oval dimple that could be readily drilled or dremelled out, returning it to free state capacity. There is no horizontal serration, as with some S&W mags that I have seen that have long horizontal indents on both broad sides of the magazine, and a serrated line thru the rest of the circumference such that it will split in two if the indents are dremelled out. A reason to not buy S&W, or at least relevant offerings of theirs. I think there is another manufacturer that does the same, maybe also in the Mass/Conn area, but I forget.
All my Sig crippled mags just have a dimple. Quarter inch drill and you’re back to unrestricted.
 
FYI I know someone who was stopped in Boston at gunpoint because of a "man with gun" call - not sure if be was printing, wind blew his jacket open, etc. Cops disarmed him and unloaded his magazine. He was not arrested and was eventually let go. Point being, it's possible for cops to be inspecting your mags without it being any sort of add-on offense.
 
FYI I know someone who was stopped in Boston at gunpoint because of a "man with gun" call - not sure if be was printing, wind blew his jacket open, etc. Cops disarmed him and unloaded his magazine. He was not arrested and was eventually let go. Point being, it's possible for cops to be inspecting your mags without it being any sort of add-on offense.

Doesn't mean they actually "inspected" anything, though. Of course I'm only basing this opinion on the premise that a lot of cops dont want to make "fake problem A" into "actual problem B C or D" etc. Obviously if you get pulled over by DoucheLeo Badge #6969 or something, virtually anyone can get in trouble for anything.

Things like AWB charges dont typically "emerge from an LTC holder on the side of the road" they emerge from things like 209A confiscations (but even in many of those, cops dont give a
shit. ) or more commonly an actual arrest and a corresponding full blown criminal investigation. I have had FFL buddies tell me stories of PD pickups where they would go to a 209A retrieval for a client and then upon getting there and logging all the shit in had to go to the client and be like "Dude I cant transfer most of your stuff back, a lot of it isn't legal in MA" etc. In one case a dealer told me about a guy who had an AR confiscated and you could take off the muzzle device by just turning it with your fingers... [rofl] police never saw it, customer got RO vacated, and he was moving out of MA so MA dealer just logged out and shipped the guns to a dealer in the "free" state he moved to, etc.
 
Doesn't mean they actually "inspected" anything, though. Of course I'm only basing this opinion on the premise that a lot of cops dont want to make "fake problem A" into "actual problem B C or D" etc.
They were more than happy to chase this one - they called his town's CLEO and attempted to get his LTC pulled over nothing. Thankfully he's a lawyer and was friendly with said CLEO, from what I understand. He told me that he probably would've gotten arrested if he had mags over 10rnds but he's confident he would've won in court.

Unfortunately, as we all know, a lot of MGL is gray at best. What's a good enough mag block? What's the correct way of attaching a muzzle device? What's the legal way of permanently securing a stock? What's the BAC limit for carrying? Is a .458 mag illegal because it can hold a lot of 5.56 rounds? The list goes on and on. I have no clue if some of the stuff I own/do would be deemed legal in court - I just do my best to follow the law as best as I understand it and hope I don't need to test it in front of a judge. Risk tolerance is a big factor in this state unfortunately.
 
They were more than happy to chase this one - they called his town's CLEO and attempted to get his LTC pulled over nothing. Thankfully he's a lawyer and was friendly with said CLEO, from what I understand. He told me that he probably would've gotten arrested if he had mags over 10rnds but he's confident he would've won in court.

Unfortunately, as we all know, a lot of MGL is gray at best. What's a good enough mag block? What's the correct way of attaching a muzzle device? What's the legal way of permanently securing a stock? What's the BAC limit for carrying? Is a .458 mag illegal because it can hold a lot of 5.56 rounds? The list goes on and on. I have no clue if some of the stuff I own/do would be deemed legal in court - I just do my best to follow the law as best as I understand it and hope I don't need to test it in front of a judge. Risk tolerance is a big factor in this state unfortunately.

So basically he got a Zebco treatment but not the whole surf casting rod?
 
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