AR pistol with fixed Mag? (In mass )

[amm5061]

I don't see why it wouldn't. Same diameter case. Similar OAL.

This. There's no reason why they wouldn't work. .300 Blk is just a .223 case necked up to take the .30 cal bullet.

As to not doing one for .300 blk, well, I don't have anything else that eats it, so for the first one I kept it simple. Theoretically you could do any caliber you want, you'd just need to change out the fixed magazine for a caliber appropriate one. Something like a Lancer with a single stack follower would work great for large bore rounds (.458 SOCOM/.450 Bushmaster/.50 Beowulf), though you loose the ability to use the side loaders for any caliber that doesn't use .223 as a parent cartridge. Top loading isn't that bad, and really only slightly more annoying than loading magazines the normal way without a speed loader.

Might do a .300blk one day, but right now I can't really afford to start stockpiling another caliber.

 

[Dennis in MA]

I almost went 300blk. In the end, I decided to stick with 5.56. There is some decent ammo for it and I figured that was AOK. With the short bbl, you still get the terminal effects of the 5.56 at close range. This isn't a 50yd gun. It's probably not a 20yd gun. My house is only 40-ish feet at the longest point. In the back yard, I might get 100-120 feet from woods-to-woods. That would be extreme for this firearm.

 

[Dennis in MA]

The nice thing is you can always get another upper. I might try it some day. I went the 10.5 route. Agree that 5.56 is not 7.5 worthy.

Do you people have any idea how much money NES costs me. Damn you people!! Lol

 

[Viper22]

Take a look at the performance/gel tests of the 194 grain Lehigh Defense 300 Blackout offerings. Looks like a good HD option.

 

[Shawnyc]

Love 300BLK, wish we could have suppressors in MA though. If you keep loaded mags around make sure you label the caliber on them!

 

[amm5061]

Now - looking at 458 SOCOM or 450 Bushmaster, that may be worthy of another build. IIRC there are 30rd mag bodies with a specific follower for the big bore rounds. Something like 10rds of 458 fits in a 30rd mag body. Just imagine how much of a thumper a 458 pistol would be!

Tromix Restricted State, Compliant Magazines - Tromix Lead Delivery Systems

Pin one of those. .458 SOCOM is a fun round, but it does get expensive to shoot. Kicks like a mule, too. Tony also sells completed 8" uppers for .458 SOCOM, 12" uppers for .450 Bushmaster, and 10.5" .375 SOCOM and .50 Beowulf uppers. I've got a 16" Tromix barrel for my .458 SOCOM straight pull bolt action AR and it's more accurate than I am.

Truthfully, if you want to go the shortie big bore route, I would get a tax stamp on a rifle lower. You're gonna want a good buttstock to help absorb that recoil. Also make sure you get a big bore style upper receiver. A standard .223/5.56 upper has to have the ejection port opened up slightly to allow reliable ejection of the larger cases, but a .450/.458/.50 upper has the ejection port already milled out a little more.

Agree that 5.56 is not 7.5 worthy.

I disagree--7.5" is perfectly fine with 5.56. Mine groups beautifully at 50 yards, and the only reason I haven't stretched it out to 100 yet is a.) laziness and b.) lack of time to get back to the range. It's an eminently workable CQB upper. Ideal for home defense, though with all carry and HD guns I would make sure to put a couple hundred rounds of your ammo of choice through it to ensure reliability and to know how it performs.

That said, I also went with a 10.5" that will eventually go on my SBR when I get the stamp back.

 

[joe1231913]

Ok cool, what a nightmare to have anything another other than an A2 on a 7.5". The rifle on top is a .22, all good there.
View attachment 278024 View attachment 278025

I see a JC Arms lower there...thanks for the business!

 

[epinero]

I see a JC Arms lower there...thanks for the business!

You're very welcome. Both Fixed mag lowers are JC lowers, very happy with them. Thank you for a quality product. Any thoughts of making AR10's?

 

[joe1231913]

You're very welcome. Both Fixed mag lowers are JC lowers, very happy with them. Thank you for a quality product. Any thoughts of making AR10's?

Maybe in the future, as of right now we are overwhelmed with making the standard caliber platform. We only have one CNC machine unfortunately.

 

[Stone_Cutter3579]

Since fixed mag AR seems to be here to stay for some time (ugh)…would the Cross Armory quick pin and safe mag system be compliant with MA laws? Looks a lot better than having to use a MA loader


View: https://m.youtube.com/watch?v=MuAN52aQfgU

 

[amm5061]

Since fixed mag AR seems to be here to stay for some time (ugh)…would the Cross Armory quick pin and safe mag system be compliant with MA laws? Looks a lot better than having to use a MA loader


View: https://m.youtube.com/watch?v=MuAN52aQfgU

IANAL, but I'm gonna say no. Read up on the JC Arms case where the cops destroyed a fixed magazine to remove it and put their own standard cap mag in its place.

Any system that allows the magazine to be easily removed without some serious disassembly leaves you open to the same treatment.

 

[Viper22]

Yeahhhhh.....that's not too "permanently fixed" IMO. While the MA Lock isn't the best looking way to fix a mag - There is no way to remove it without destroying some metal. It is still fixed in place when the upper & lower are separated.

 

[Viper22]

Below are the beginnings of the AR9 en route to me. Very excited for this one too.

Now that looks like it will be fun.

 

[DJBrad]

Don’t pay attention to the royal mess up of them sending me a 5.56 lower instead of the 9mm lower that I ordered. That’ll get fixed. Other than that snafu I’ve been very happy with their products.

 

[Aaron[MA]]

Oooooh this is gonna be a fun one. The ceracote job is fantastic.View attachment 282873 View attachment 282874 View attachment 282875 View attachment 282871

View: https://m.youtube.com/watch?v=V268Qk6-xsw

 

[amm5061]

View attachment 284066 A quick dry fit with the 80 percent 9mm lower. I think this will turn out pretty darn good. Love the looks of it. Could do a pistol tube buffer instead but I do like the SBA3 braces. Preban glock fun mag stuffed in there for a test. Would look more balanced with a smaller mag. A reflex sight would do well or the Holosun one I use on another which is of very good quality. When it gets built it will probably get my own version of a fixed 10 rd glock mag with a drill, tap, and weld.

Let us know how top loading the Glock mag works. Keep a baseplate tool handy in case you get a jam.

 

[DJBrad]

Let us know how top loading the Glock mag works. Keep a baseplate tool handy in case you get a jam.

Yes that may prove challenging but will update when that occurs.

 

[Mountain]

This pipe dream GTG or a problem?

• Pre-Healy lower purchased years ago on a 4473 but never built into anything. (not that pre-Healy means anything for a non-AWB build)
• Install fixed 10-round mag, then assemble rest of the lower.
• Pistol brace from one of the known vendors w/ ATF blessing. (edit- will discard/destroy pistol brace and go brace-less if the law changes or go through the SBR process)
• 10.5" upper in 300 BLK.
• EFA10 as a 30-cal non-high capacity pistol.

Mass OK way to do it? Thanks...

 

[DJBrad]

This pipe dream GTG or a problem?

• Pre-Healy lower purchased years ago on a 4473 but never built into anything. (not that pre-Healy means anything for a non-AWB build)
• Install fixed 10-round mag, then assemble rest of the lower.
• Pistol brace from one of the known vendors w/ ATF blessing.
• 10.5" upper in 300 BLK.
• EFA10 as a 30-cal non-high capacity pistol.

Mass OK way to do it? Thanks...

It all depends on the lower. Was it pistol? If so then ok. Was it rifle? Then no go.

 

[Mountain]

It all depends on the lower. Was it pistol? If so then ok. Was it rifle? Then no go.

Neither.

 

[DJBrad]

Then if 80%, 0%, multi cal go for it.

AFAIK when a lower is produced by a manufacturer it’s either rifle or pistol. I may be wrong on this.

 

[amm5061]

Neither.

If it was 4473'd as "Other" then you're g2g, but honestly I wouldn't waste a good pre-Healey ban lower on fixed mag. Save it and get yourself a virgin new production lower.

 

[Mountain]

Then if 80%, 0%, multi cal go for it.

AFAIK when a lower is produced by a manufacturer it’s either rifle or pistol. I may be wrong on this.

If it was 4473'd as "Other" then you're g2g, but honestly I wouldn't waste a good pre-Healey ban lower on fixed mag. Save it and get yourself a virgin new production lower.

Sounds like a good opportunity for an 80%.

 

[DJBrad]

If it was 4473'd as "Other" then you're g2g, but honestly I wouldn't waste a good pre-Healey ban lower on fixed mag. Save it and get yourself a virgin new production lower.

That is if the virgin new production was a fair price. Here in Ma is there anyway to get one cheaper than $275? Unless you’re building it there is indeed a increased cost on the build.

 

[amm5061]

That is if the virgin new production was a fair price. Here in Ma is there anyway to get one cheaper than $275? Unless you’re building it there is indeed a increased cost on the build.

If you find the right FFL to inbound it for you.

You could also just pick up an 80% for $40-60. More fun and you get the satisfaction of having really built it yourself.

 

[DJBrad]

If you find the right FFL to inbound it for you.

You could also just pick up an 80% for $40-60. More fun and you get the satisfaction of having really built it yourself.

Find me that ffl :emoji_grin:

 

[Mountain]

You guys must have missed out on some of the group buys a few years back. I can't remember what I actually paid for stripped lowers but seems like it was ~$60, give or take.

I may check and see if I have an 'other' which I think was the way to do it in most cases. Assuming I have one, no biggie if I use it for this purpose. If I move to a free state, I still want an AR pistol and at that point can machine out what made the mag permanently affixed.

On another note, out of curiosity I contacted Mean Arms regarding their fixed mag loading device and 300 BLK. They confirm that although it was not designed for that, it will work just fine. Quick response and nice folks.

 

[amm5061]

No reason why .300 BLK shouldn't work in them. Case is just a necked up .223.

 

[DW357]

Oooooh this is gonna be a fun one. The ceracote job is fantastic.View attachment 282873 View attachment 282874 View attachment 282875 View attachment 282871

That looks sweet. Who makes that grip??

 

[DJBrad]

That looks sweet. Who makes that grip??

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