CZ Scorpion Pistol to SBR

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The Annoyed Man
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Re: CZ Scorpion Pistol to SBR

#16

Post by The Annoyed Man »

Regarding the CZ SBR...... I recall a recent article from TFB about CZ and other brands of pistols with folding braces being reclassified as “other” and seized by ATF - something to do with the overall length of the weapon’s overall length with the brace extended versus folded. With the registered SBR, is there a risk that ATF would do the same thing to SBRs that have folding stocks and seek to seize them? If you could provide some additional clarity on that whole issue, that would be great. Sometimes these kinds of articles are written by someone who does not have your ATF credentials, and who may be hyperventilating a little bit.

Regarding vertical forend grips...... I’ve always avoided them because as a general thing, I prefer a more traditional way of gripping my rifle with my off hand.,...... with one exception. I built a replica M16A4 last year, and the KAC vertical forend grip was an issue item along with the KAC M5 RAS forend assembly. The vertical grip does seem to help manage the weight of the full length rifle, making it easier to keep the thing pulled into my shoulder .....although I’ve shot for years without using one, on heavier rifles, and had no problems. Mostly, it’s there for the sale of visual authenticity.

Regarding your AR SBR pictured above..... I built a 10.5” .300 Blk SBR a while back, and I originally used that same Minimalist stock that’s one yours. A few months back, I swapped it out for a Magpul MOE ACS-L carbine stock, which I prefer. The Minimalist stock is well made, but I had the problem of always snagging the toe of the stock on things like folds in clothing and such when mounting the stock. The Magpul unit doesn’t weigh too much more, and it feels more like a buttstock to me, with a better cheek rest.

Edited to add...... is there any other reason than convenience for using a locking lug type of mount for a suppressor? I have an Obsidian pistol suppressor, and it is direct thread mounted. Are the lug type mounts as secure in terms of keeping the can concentric to the bore?
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Re: CZ Scorpion Pistol to SBR

#17

Post by Scott B. »

The Annoyed Man wrote: Thu Jun 07, 2018 10:16 am Regarding the CZ SBR...... I recall a recent article from TFB about CZ and other brands of pistols with folding braces being reclassified as “other” and seized by ATF - something to do with the overall length of the weapon’s overall length with the brace extended versus folded. With the registered SBR, is there a risk that ATF would do the same thing to SBRs that have folding stocks and seek to seize them? If you could provide some additional clarity on that whole issue, that would be great
...

Edited to add...... is there any other reason than convenience for using a locking lug type of mount for a suppressor? I have an Obsidian pistol suppressor, and it is direct thread mounted. Are the lug type mounts as secure in terms of keeping the can concentric to the bore?
I had to go back and reread that article as I only skimmed it when it was first published. It appears that particular situation is unique to the great state of Connecticut and their interpretation of what a pistol/rifle/eveeeeeel black gun are.

INAL, this is just general info.

The advantage of an SBR is that you don't have to worry about some new interpretation of what a pistol is or is not. You've paid for the 'privilege' of going short with whatever stock rocks your boat. There are occasional rulings on new firearms when it comes to the NFA side, but it's pretty static.

Unlike the ground we find ourselves on w/ what is or is not a pistol, based on a brace 'designed' to accommodate those unable to grasp a pistol normally.

For your SBR, or SBS, the overall length, or even barrel length, provided at the time of your stamp application doesn't have to be adhered to after approval. You can go shorter, longer, whatever. I think it's recommended that you have the ability return to original config if you want to sell it on. However, since there's really no secondary market for NFA items --- save for full auto -- then that's basically moot.

AND, if you get tired of the NFA game. You can return your item to title 1 configuration, pistol or rifle, and let ATF know to take it off the books.


Suppressors. W/ a mount system you have more confidence that the suppressor is staying on and is lined up correctly (provided the mount itself was lined up correctly when installed). Direct thread cans, particularly on rifles, sometimes back off under continued firing. That said, people have screwed up when using some of the different mount systems too.

To me the advantage of the mount system is the ability to move to other rifles without much fuss.

Now w/ pistols, cans are almost exclusively direct thread.
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Re: CZ Scorpion Pistol to SBR

#18

Post by SigM4 »

The Annoyed Man wrote: Thu Jun 07, 2018 10:16 am Edited to add...... is there any other reason than convenience for using a locking lug type of mount for a suppressor? I have an Obsidian pistol suppressor, and it is direct thread mounted. Are the lug type mounts as secure in terms of keeping the can concentric to the bore?
I'll echo what Scott said on the subject. At least in the case of the 3-lug mount, I shouldn't have to worry about it backing off after an extended string of fire. Couple that with the easy on/off attachment and it makes for easily swapping between pistol caliber carbines. Rugged makes a very nice 3-lug adapter for your Obsidian (I have an Obsidian and the adapter in addition to my Octane) in case you ever have the desire to suppress something in this vein down the road.

As far as the lockup, yes, very positive lockup and keeps the can nice and tight without any wiggle.
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Re: CZ Scorpion Pistol to SBR

#19

Post by The Annoyed Man »

SigM4 wrote: Thu Jun 07, 2018 12:50 pm
The Annoyed Man wrote: Thu Jun 07, 2018 10:16 am Edited to add...... is there any other reason than convenience for using a locking lug type of mount for a suppressor? I have an Obsidian pistol suppressor, and it is direct thread mounted. Are the lug type mounts as secure in terms of keeping the can concentric to the bore?
I'll echo what Scott said on the subject. At least in the case of the 3-lug mount, I shouldn't have to worry about it backing off after an extended string of fire. Couple that with the easy on/off attachment and it makes for easily swapping between pistol caliber carbines. Rugged makes a very nice 3-lug adapter for your Obsidian (I have an Obsidian and the adapter in addition to my Octane) in case you ever have the desire to suppress something in this vein down the road.

As far as the lockup, yes, very positive lockup and keeps the can nice and tight without any wiggle.
Both of my rifle suppressors mount by means of a flash hider or muzzle brake with a proprietary mount. I have an AAC flash hider on 3 of my rifles, to fit my AAC can; and I have Griffin Armament taper mount muzzle brakes on 3 other long guns to mount my Form 1 can. The AAC can always locks up tight because it uses a 51T ratchet.But the Form 1 cans we own have to be checked periodically to make sure they haven’t shot loose. if you tighten them down onto the taper too much, you can’t get them off without waiting for everything to cool down sufficiently.

I have tried swapping my Obsidian can between a Glock 17 and a Keltech Sub 2000 carbine, but there are issues. For instance, my can is the Obsidian45, and it works fine on both 9mm and .45 pistols. I had purchased a 9mm end cap for it, which worked fine on the 9mm pistol. But when I shot it configured that way on the Keltec (with a fixed barrel spacer in place of piston), I got a strike on the 9mm end cap that ruined it - a $65 lesson. Going back to the .45 end cap fixed the problem, but point of impact shift is so severe that there wasn’t enough adjustment range in the PA RDS to zero the carbine. Back to square one. I’m not going to bother replacing the 9mm end cap, as the .45 version with 9mm subsonics is still REALLY quiet.

Also, even if you put a 3-lug mount on both weapons, you still have to remove the piston and substitute a fixed barrel spacer anyway to go from a pistol to a carbine. So unless I’m missing something, I don’t see an advantage there. But I can see how it would make switching from pistol to pistol, or carbine to carbine easier.......just not from pistol to carbine or visa versa.
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SigM4
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Re: CZ Scorpion Pistol to SBR

#20

Post by SigM4 »

The Annoyed Man wrote: Thu Jun 07, 2018 2:07 pm Also, even if you put a 3-lug mount on both weapons, you still have to remove the piston and substitute a fixed barrel spacer anyway to go from a pistol to a carbine. So unless I’m missing something, I don’t see an advantage there. But I can see how it would make switching from pistol to pistol, or carbine to carbine easier.......just not from pistol to carbine or visa versa.
I wouldn’t recommend a 3 lug on a pistol simply because the recoil with the Nielsen Device could do funky things with the 3 lug engagement. I’ve never heard of it happening, but I’d rather be safe than sorry. Plus, it just looks weird on a pistol. :mrgreen:
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Re: CZ Scorpion Pistol to SBR

#21

Post by SQLGeek »

Scott, I dig that color. It reminds me of plum AK furniture which I am also rather fond of.
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Re: CZ Scorpion Pistol to SBR

#22

Post by Scott B. »

Hmmmm, something seems to be missing from this pile of parts. :mrgreen:

I've sent the barrel off to have something interesting done to it. Hope to see it back by the end of the week.

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Re: CZ Scorpion Pistol to SBR

#23

Post by SigM4 »

Oh boy, can’t wait to see the barrel on its return.

Did you happen to see where HBI is now selling their own K length barrels that have the three lug machines into it along with 1/2x28 threads? Wish those had been around earlier as I’d have opted for that over the three lug adaptor I have on mine.
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Re: CZ Scorpion Pistol to SBR

#24

Post by Scott B. »

CZ Scorpion aftermarket is humming right along. Ton of great stuff out and coming out.

I was running one of the HBI tri-lug adapters on my Scorpion before I tore it all down. Testing out an old MP5 9mm suppressor I picked up cheap that's headed to my MP5 when it gets finished.
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Re: CZ Scorpion Pistol to SBR

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Post by Scott B. »

Let me preface this all by saying I'm absolutely cheating. This is a demo platform / personal toy. We show this to customers to say "look what you can do!" I'm licensed by ATF to do all this without waiting AND pay a yearly tax for the privilege plus fun paperwork.

Here's the barrel as I sent it off to be modified. This is a Scorpion barrel that had been re-profiled a bit from standard. You'll also notice at the bottom of the picture the trunnion from the HBI Industries handguard which is a key component of this modification.

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Sent it off to the clever folks at Innovative Arms in South Carolina, https://innovativearms.com/

They sent the barrel back with a little extra added. Here the trunnion has been mounted, the barrel is sleeved, and a suppressor integrated. This whole piece is serviceable. It's not permanently attached, although the barrel has been permanently modified. When I clean it I'll have to grab some photos of what they do, it's very clever.

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Here's the muzzle end showing a little better the very unique profile this suppressor has which is why it's specific to the HBI handguard.

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Here we see the barrel mated to the receiver halves. To get the barrel out you have to completely disassemble the Scorpion as shown in my previous posting.

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Handguard slipped over the assembly. I'll note on the squared off handguard, you loose the ability to mount anything on the first two muzzle end mlok slots. I only lost my QD mount position, I intend to move it back on the handguard.

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The whole thing back together and looking pretty darn sexy, I think.

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And all folded up to go back into my range bag.

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Compare the new setup length to a more traditional can I had on it last.

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Okay, last bit. I love this new setup. It's really great, super cool, and I'm going to really enjoy showing it off. But, the one thing that impressed me most? When I remounted the MRO sight that's sitting on a Midwest Industries mount? It was bang on zero. That's after having the two receiver halves apart!
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Re: CZ Scorpion Pistol to SBR

#26

Post by PriestTheRunner »

Wow! Not gonna lie, that CZ looks like it came straight out of Judge Dredd... lol

Were you able to get your hands on a decimeter and determine the "exact" decibel drop?

Cool build! :tiphat:
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Re: CZ Scorpion Pistol to SBR

#27

Post by Scott B. »

Took an infrared thermometer to the range, but not a sound meter because it was indoors. I'll try to get an average next weekend.
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Re: CZ Scorpion Pistol to SBR

#28

Post by Scott B. »

Shot it outdoors this weekend, much fun was had. I am going to have to change the vertical grip. Need something with a little more thermal protection. Ordered an MP5 style grip from A3 Tactical. Hope to have it before the weekend.

Had too much fun and forgot to get sound levels.

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Re: CZ Scorpion Pistol to SBR

#29

Post by SigM4 »

I’m now undecided if I’m going to transfer my SBR’d upper over to the new Manticore Arms/CZ USA bullpup stock, or just buy anothe carbine to convert with the stock (or wait till CZ starts selling them as factory rifles). Either way I’m getting one.

Scorpion Bullpup

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Re: CZ Scorpion Pistol to SBR

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Post by Scott B. »

You'll have to post the build and review. There are very few bullpup that I like, but am very curious about this conversion.
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