Not enough barrel!!!!

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rotz
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Not enough barrel!!!!

Post by rotz » Tue Feb 18, 2020 3:46 pm

Hey guys!
I live in a not so free country that although doesn't regulate suppressors, heavily regulates guns and especially barrels. This makes buying a new barrel very ilegal so here is my issue:

Just bought a new cz p07 handgun in .380 (biggest caliber you can own) and need to fit it with a supressor so I can actually practice without the neighbors freaking out but I don't have enough barrel sticking out of the slide! I have a lathe and I was wondering if someone has done this or if you think it's doable to cut some sort of step on the last few mm of barrel, and press fit an "extension" that will have the male threads that can accommodate a supressor... What is you opinions?

Thanks!!!
BR

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T-Rex
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Re: Not enough barrel!!!!

Post by T-Rex » Wed Feb 19, 2020 8:36 am

Bore and internally thread.
Make a male to male adapter, that threads into barrel and supplies threads for silencer.
It's done all the time, for pistol barrels, such as this.
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a_canadian
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Re: Not enough barrel!!!!

Post by a_canadian » Wed Feb 19, 2020 4:27 pm

I'm curious how the crown gets finished when counter-boring for an adapter like this, or even more so when something like a 10-22 bull barrel gets used as a short barrel with integrally machined suppressor as we've seen displayed a couple of times on these forums. Seems getting the finish just right on the crown of the barrel would be challenging to put it mildly. Too easy to leave a slight burr or some irregularity when going deeply into the barrel, without any easy access to polish it back to a proper exit for the projectile. But yes, of course counter-boring, accurately threading and making a male-to-male adapter is the obvious solution. Been done lots of times on everything from a .22lr Bobcat to considerably larger bores.

ECCO Machine
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Re: Not enough barrel!!!!

Post by ECCO Machine » Wed Feb 19, 2020 10:48 pm

a_canadian wrote:
Wed Feb 19, 2020 4:27 pm
I'm curious how the crown gets finished when counter-boring for an adapter like this, or even more so when something like a 10-22 bull barrel gets used as a short barrel with integrally machined suppressor as we've seen displayed a couple of times on these forums. Seems getting the finish just right on the crown of the barrel would be challenging to put it mildly. Too easy to leave a slight burr or some irregularity when going deeply into the barrel, without any easy access to polish it back to a proper exit for the projectile. But yes, of course counter-boring, accurately threading and making a male-to-male adapter is the obvious solution. Been done lots of times on everything from a .22lr Bobcat to considerably larger bores.
I counterbore with a sharp square end mill for internal barrel threading, bring the ID to correct minor with carbide boring bars.

It will leave a very sharp 90° crown, and it has never negatively impacted accuracy in my experience. I've done it dozens of times.

That said, I usually do very fine (36 or 40 pitch) external threads on .380/9mm and larger barrels with female-Male adapters because the barrel walls are generally not thick enough to support the requisite internal threads for a male-male adapter.
FFL07/02SOT Gunsmith & Machinist

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John A.
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Re: Not enough barrel!!!!

Post by John A. » Sat Feb 22, 2020 9:35 am

Ecco threaded my cz75 clone like that and it's as accurate as ever (which is good because it was the most accurate 9mm handgun that I own).
I don't care what your chart says

bwp777
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Re: Not enough barrel!!!!

Post by bwp777 » Tue Feb 25, 2020 9:43 am

don't they make bullets that are like a very fine sand paper and you shoot them to lap the barrel or something like that? I would think this could help refine the bore if there were small inconsistencies hanging around.

alordnapa
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Re: Not enough barrel!!!!

Post by alordnapa » Tue Feb 25, 2020 1:39 pm

When you make a M/M adapter for internal threads, do you thread the internal threads left hand, or right handed? I don't suppose that anyone makes adapters and tools ( Piloted reamers, etc.) like the CNC Warrior kits?

#40Fan
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Re: Not enough barrel!!!!

Post by #40Fan » Tue Feb 25, 2020 9:05 pm

I'd make the internal threads right handed so you don't unscrew the adapter when tightening up the suppressor. In fact, I'd rocksett it in.

Ridge Runner
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Re: Not enough barrel!!!!

Post by Ridge Runner » Sun Mar 29, 2020 3:30 pm

Look at the design of the Ruger SR22 threaded barrel. There is no barrel protrusion. There is an adapter that replaces the thread protector and extends the barrel profile about 1/2" while also increasing the threaded diameter. You are likely to be better off with an adapter than with some other scheme to lengthen your barrel.

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T-Rex
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Re: Not enough barrel!!!!

Post by T-Rex » Sun Mar 29, 2020 3:49 pm

Ridge Runner wrote:
Sun Mar 29, 2020 3:30 pm
Look at the design of the Ruger SR22 threaded barrel. There is no barrel protrusion. There is an adapter that replaces the thread protector and extends the barrel profile about 1/2" while also increasing the threaded diameter. You are likely to be better off with an adapter than with some other scheme to lengthen your barrel.
The SR22 has external threads, already provided. The OP doesn't.
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Ridge Runner
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Re: Not enough barrel!!!!

Post by Ridge Runner » Sun Mar 29, 2020 6:02 pm

T-Rex wrote:
Sun Mar 29, 2020 3:49 pm
Ridge Runner wrote:
Sun Mar 29, 2020 3:30 pm
Look at the design of the Ruger SR22 threaded barrel. There is no barrel protrusion. There is an adapter that replaces the thread protector and extends the barrel profile about 1/2" while also increasing the threaded diameter. You are likely to be better off with an adapter than with some other scheme to lengthen your barrel.
The SR22 has external threads, already provided. The OP doesn't.
I am missing your point. Help me understand. The OP has a standard unthreaded barrel on a standard semiautomatic pistol. If threading the barrel why not thread the outside like 99% of all threaded barrels? Since the front of the firearm does not allow for a threaded connection without breaking the plane the options I see are to reduce the barrel muzzle diameter to accommodate either an adapter or to accommodate a suppressor with a female connection that extends at the diameter of the original barrel or less. Smaller diameter would create a risk of catching on the edge of the joint.

Should I understand the OP wants to connect without threads? What should I understand that I am missing?

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T-Rex
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Re: Not enough barrel!!!!

Post by T-Rex » Sun Mar 29, 2020 6:30 pm

Ridge Runner wrote:
Sun Mar 29, 2020 6:02 pm
I am missing your point. Help me understand.
Not that the OP's question has already been answered (correctly), several times, but you simply advise him to use an adapter an in no way advise how to do this (as the other replies have). As I said, "The SR22 has external threads... The OP doesn't".

Yes, plenty of handgun barrels have external threads. However, the vast majority of those also have a barrel that extends beyond the slide. IF the adapter isn't installed, a barrel w/ female threads can still fire, w/o requiring a thread protector. Not having one will surely ruin any exposed, male, threads. Thin barrels don't usually allow for an external thread protector to utilize wrench flats and knurling could, also, become a problem with slide operation.
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