Updated October 21, 2010
Dead links fixed, some minor edits and updates.
Ask and you shall receive. Hope this helps people out. Please PM with any errors, suggestions, or further questions.
------
Armalite AR180B Frequently Asked Questions
By Bryce Volk (aka Armedsask )
This FAQ has been written to hopefully answer all the questions the author has been repeatedly asked over the years pertaining to the AR180B. This FAQ is geared specifically towards the Canadian firearms market. To suggest a question, comments, or you’ve found an error, please email me at: brycevolk@sasktel.net
The Basics: Before You Buy
Q: Where do I buy an Armalite AR180B?
A: In Canada, the Armalite importer is Wolverine Supplies of Virden, Manitoba. Many other gun shops and dealers in Canada will sell the AR180B but they all come in through Wolverine Supplies. Sadly, the AR180B is out of production so any new rifles are not going to come into the country. There is assurances than Armalite has not abandoned the design.
Q: What is the difference between the AR180B and the AR180B-2?
A: Currently, the AR180B is the version with a threaded muzzle, it is restricted due to barrel length. The AR180B-2 is the California and Canada legal version with the integral muzzle brake. It is non-restricted in Canada. However, before the threaded muzzle version, the AR180B was the model with the integral muzzle brake. To make things easy, all AR180B rifles in Canada are non restricted as I am unaare of any restricted versions being imported.
The naming is pretty backwards as the AR180B-2 is actually the first version of the AR180B type rifle, and was originally called the AR180B. With the sunset of the Assault Weapons Ban in the US, Armalite started threading the muzzles for flash suppressors. They continued to manufacture the "AW ban" version with the integral muzzle brake, as the AR180B-2, for states like Commifornia and Canada.
Q: How much does the AR180B cost?
A: At the date of writing, November 2006, Wolverine lists the AR180B at just over $1000. This includes the rifle, manual, and one 20 round magazine.
Q: But isn’t is made of plastic?
A: No, it’s made from a high strength polymer with steel reinforcements where required. You do know that Glocks, airplanes, and cars are also plastic, right?
Q: I’ve heard the front pivot pin is weak point and will break off. Is this true?
A: Sure it is, if you abuse your rifle. If the upper receiver is allowed to fall unaided and slam open, it will weaken the pivot pin. If you treat your rifle with respect, you won’t have any issues. I’ve owned my AR180B for over 4 years and it has seen lots of field use, it is no safe queen or range baby. Not to mention my rifle has more weight hanging off the upper than most will ever see. I’ve never had a problem.
If you do some how manage to break your lower at the pivot pin, it’s a very good bet you’ll get it replaced free of charge.
Q:Can you fire it left handed or does the cocking handle move after every round? Why I ask is cause the British SA 80 has a similar cocking handle design and it cannot be fired lefty. The handle smacks you in the teeth, trust me I know from experience.
A: Yes, the AR18 and SA80 operating systems are extremely alike. The SA80 is, for the most part, copied from the AR18 operating system. That being said, the SA80 is a bullpup, putting the action right next to your face. The AR180B is not. If you are getting a bolt handle in the face, you're doing something completely wrong.
Q: I'm a lefty, can I change the safety to the other side?
A: No, you can't just flip the factory safety around to the other side. Armalite does offer an ambidextrous safety as an after-market part. I've also seen home built mods where the stock safety was drilled and tapped on the right side and the end of an AR15 safety was screwed in to make a home made ambi-safety.
Q: What is the classification of the AR180B?
A: Being that the AR180B is a new rifle it classification is based on barrel length. As it is a semi-auto center fire the barrel length must be over 18.5” for the rifle to be non-restricted. There are currently 2 version of the AR180B. The integral muzzle brake version which came out during the United States “Assault Weapons Ban” days is non-restricted. After the sunset of the Assault Weapons Ban a version with a factory threaded barrel was introduced, this version is restricted due to barrel length.
Q: Isn’t the AR180B a variant of the prohibited AR180, how can it be non-restricted?
A: You’re trying to use logic to explain Canadian Firearms law, it won’t work. Now sit back and enjoy, this explanation is long and confusing. The reason the AR180B is not classed as a variant of the prohibited AR180 is due to some major operating changes. In Canada, a variant is determined by a few items, one being the operating system or action. As the AR180B uses an AR15 type trigger group, it is not an AR180 variant in that respect. It also uses AR15 magazines, another notch for not being an AR180 variant. By this logic it could be called an AR15 variant but then the action and receiver comes into play. The AR180B is gas operated using a short stroke piston, a completely different recoil system (i.e.: no buffer tube), and an entirely different receiver. So now we look at it and say, “It’s not an AR180 variant and it’s not an AR15 variant. Therefore, it must be a new type of rifle.” Bingo. Now we look at the barrel length, low and behold it’s long enough to be non-restricted.
Q: That was confusing, how do you understand Canadian Firearms law?
A: No one understands Canadian Firearms law, we just try to understand how small parts of it work. Mostly we bulls**t our way through it.
Q: I love the AR15 but want a non-restricted version, is the AR180B a good choice?
A: The Armalite AR180B is NOT an AR15 type rifle. If you purchase it thinking that you are getting a non-restricted AR15, you will be disappointed. The AR18 was designed as a cheaper option to the AR15. It was sheet metal construction with a bolt carrier system that allowed for huge tolerances in manufacturing. It is not an AR15 by any stretch of the imagination.
Now I Own One: Let’s make it function flawlessly
Q: My rifle fires and ejects but fails to load a fresh round. If I cycle the bolt manually, the rounds load just fine.
A: Check your gas block. If it is misaligned, or to far forward or back, this could restrict gas flow to the piston. The rifle will fire and eject rounds but the piston won't have enough power to push the bolt back far enough to chamber a fresh round.
Q: My firing pin is stuck forward, what do I do?
A: Sometimes the hammer hitting the firing pin will deform the bolt carrier around the firing pin. The hole that the firing pin goes into will become peened around the firing pin. This is solved by simply file a chamfer around the edge of the hole.
Q: Some of my magazines don’t feed. How do I make my rifle feed reliably?
A: My rifle is one of the earlier models and suffered some feeding issues. This was quickly fixed by filing a ramp on the front of the magazine. This did not fix the problem for all magazine. Applying a small bit of epoxy to the trigger guard did. My rifle functions flawlessly for the past 4 years.
From personal experience and from talking with others I've found that Colt magazines are the worst performers in the AR180B. With the epoxy fix they function flawlessly.
New fix: CGN member G37 has come up with a better, more esthetically pleasing fix for the feeding issue. However, it requires cutting your rifle. Basically, he cut M4 feed ramps into his barrel nut and front receiver trunnion.
Update: From talking with owners of new rifles it now looks like Armalite is adding the "M4 Style" feed ramps to new rifles straight from the factory. This should solve all feeding and magazine issues.
Q:I've removed and reinstalled my gas block for ### reason, now my rifle doesn't eject spent rounds consistently or does not eject at all.
A: Your gas block is cockeyed and this is causing the hole in the barrel and the hole in the gas block to not line up, restricting gas flow and preventing enough power to cycle the bolt. If you do not have the stock hand guards installed, the gas block may be too far back on the barrel and that is cutting off the gas ports. You'll notice that when you have the stock hand guard installed the gas block is not tight against that little collar on the barrel. Install it a little further forward with a bit of a gap between the collar and the rear of the gas block. I think mine is about 2 mm or so. It's not precise, just eyeball it
Important Notice!
Be sure your gas block is on straight! It has come to my attention that cockeyed gas blocks will lead to excessive wear on one side of the gas piston.
Q: What parts are interchangeable between the AR180B and the AR15?
A: The trigger group (minus the safety selector), the mag catch, front and rear site components, ejector, extractor, probably some springs. That’s it.
Q: What kind of groups can I expect with my rifle?
A: From personal experience and from what I’ve been told by other users, 1 to 2.5 inch groups at 100 yards with factory ammo and irons is easily attainable by a competent shooter. Add some optics, hand loaded ammunition, and you could shrink that group down. I’ve been told as little as .5 to 1 inch groups, if not smaller.
Q: Speaking of optics, how do I mount a scope?
A: You will have to buy a scope base for your rifle. When I first got mine, this was easier said than done. Now days we are lucky as there are numerous options to choose from. I’d list them all but that would be wasting your time. When it comes to scope bases there is only one choice: www.stormwerkz.com.
Josh Miller of Storm Werkz does amazing work. He also has amazing customer service and deals with Canadians all the time. Storm Werkz ships to Canada with no issues what so ever. Place your order and wait in confidence. Great prices, great service, and fast shipping. No, I am not paid by Josh, I am just a very happy customer. However, I think I'd should be getting paid for all the promotion I do!
Can I put on folding sites?
In short, no. The AR180B site line is much lower than the AR15. To add AR15 flip up sites you would have to remove the rear site and install a full length rail on the receiver. You would then need to design and manufacture a railed gasblock, or a gasblock with an integral folding sight. If you manage this, your folding rear site will probably sit just as high as the stock rear site even when folded down, thus negating any reasoning behind doing all that work.
Q: What about railed hand guards?
A: Again, when I first got my rifle there was not much for accessories. I’d even hazard to say I pioneered the use of railed hand guards on the AR180B (just tootin' my own horn). Thankfully for you, spending over $600 to custom mount an AR15 railed hand guard won’t be necessary. Midwest Industries now offers a drop in railed hand guard that replaces the factory hand guards.
Midwest Industries railed hand guard
Minor modification is needed as the user must cut ¼” off the front of the recoil spring guide rods. Five minutes work with a Dremel or hacksaw. You can purchase that MI railed hand guards from Wolverine Supplies.
Q: I want a folding/M4/skeletal stock on my AR180B. How do I do this?
A: First you will need a stock adapter. All adapters on the market require you to permanently modify your receiver and usually mean you can not return to the factory stock. Trust me, you won’t be going back.
Again there are a few companies that offer these adapters but this author only has one suggestion. Storm Werkz offers three types of adapters. Check their site for pictures and info.
Q: Can I do anything about the trigger?
A: You sure can. As the AR180B uses standard AR15 trigger parts, however the pins are longer. You can swap out the trigger with any after market AR15 trigger group. Simple as that.
Q: Can I change the grip?
A: Not easily. The grip is molded into the polymer lower receiver and is all one piece. I’m sure it could be done but I don’t know if it would be worth the trouble and possibly ruining your receiver.
Q: Can I put a different or AR15 barrel on the AR180B?
A: Sure, you could have a custom barrel made up but that would probably cost the same if not more than the complete rifle.
The AR15 barrels and AR180B barrels have the same threads. One could theoretically thread an AR15 barrel into the AR180B barrel trunnion. Setting the head spacing would be required and the gas hole would not line up. It may be possible to make an AR15 barrel work if the gas hole was drilled specifically for the AR180B.
There is play between the upper and lower receiver, is this normal?
Yup, perfectly normal and has no affect on accuracy. If, however, you wish to remedy this purely cosmetic issue, it is simple. Grab a pair of pliers with soft jaws and slightly bend in the back portions of the upper receiver so they more tightly hold the recoil spring guide rod assembly. Don't over do it, bend tiny bits at a time!
The Other Stuff
Q: How easy is it to convert the AR180B to full auto?
A: It’s impossible as that is illegal.
Q: How do I remove the barrel?
A: You will need a barrel extension wrench. You can make your own from an old/broken AR15 bolt or you can buy one here (it will have to be modified): http://www.brownells.com/aspx/NS/store/productdetail.aspx?p=12729&s=
To remove the barrel on an AR-180B: strip everything off the upper including the front sight base, make a reference mark on the barrel and the upper receiver for realignment on reinstall, clamp the barrel in a good vise with barrel blocks, then with either a purchased or home made barrel extension wrench turn the receiver/barrel extension off the barrel. Counter clockwise, they are standard right hand threads. DO NOT try to turn the receiver by itself, you will just spin the barrel extension out of alignment with the receiver. Remember, you are turning the entire receiver off the barrel, not the barrel off the receiver.
Q: Does any one make an aluminum or sheet metal lower like the original?
A: Not at the moment. There have been numerous home built replacement receivers as well as rumors of Armalite bringing out a whole new rifle with a machined lower. This has yet to materialize.
Q: What is your area of expertise that makes you qualified to write this FAQ?
A: I've owned an AR180B for many years and have done numerous mods to it. That's my qualification. Also, I'm a big deal on the internet.
Thanks to:
Josh Miller of www.stormwerkz.com,
And every one who has pestered me with questions over the years.
Dead links fixed, some minor edits and updates.
Ask and you shall receive. Hope this helps people out. Please PM with any errors, suggestions, or further questions.
------
Armalite AR180B Frequently Asked Questions
By Bryce Volk (aka Armedsask )
This FAQ has been written to hopefully answer all the questions the author has been repeatedly asked over the years pertaining to the AR180B. This FAQ is geared specifically towards the Canadian firearms market. To suggest a question, comments, or you’ve found an error, please email me at: brycevolk@sasktel.net
The Basics: Before You Buy
Q: Where do I buy an Armalite AR180B?
A: In Canada, the Armalite importer is Wolverine Supplies of Virden, Manitoba. Many other gun shops and dealers in Canada will sell the AR180B but they all come in through Wolverine Supplies. Sadly, the AR180B is out of production so any new rifles are not going to come into the country. There is assurances than Armalite has not abandoned the design.
Q: What is the difference between the AR180B and the AR180B-2?
A: Currently, the AR180B is the version with a threaded muzzle, it is restricted due to barrel length. The AR180B-2 is the California and Canada legal version with the integral muzzle brake. It is non-restricted in Canada. However, before the threaded muzzle version, the AR180B was the model with the integral muzzle brake. To make things easy, all AR180B rifles in Canada are non restricted as I am unaare of any restricted versions being imported.
The naming is pretty backwards as the AR180B-2 is actually the first version of the AR180B type rifle, and was originally called the AR180B. With the sunset of the Assault Weapons Ban in the US, Armalite started threading the muzzles for flash suppressors. They continued to manufacture the "AW ban" version with the integral muzzle brake, as the AR180B-2, for states like Commifornia and Canada.
Q: How much does the AR180B cost?
A: At the date of writing, November 2006, Wolverine lists the AR180B at just over $1000. This includes the rifle, manual, and one 20 round magazine.
Q: But isn’t is made of plastic?
A: No, it’s made from a high strength polymer with steel reinforcements where required. You do know that Glocks, airplanes, and cars are also plastic, right?
Q: I’ve heard the front pivot pin is weak point and will break off. Is this true?
A: Sure it is, if you abuse your rifle. If the upper receiver is allowed to fall unaided and slam open, it will weaken the pivot pin. If you treat your rifle with respect, you won’t have any issues. I’ve owned my AR180B for over 4 years and it has seen lots of field use, it is no safe queen or range baby. Not to mention my rifle has more weight hanging off the upper than most will ever see. I’ve never had a problem.
If you do some how manage to break your lower at the pivot pin, it’s a very good bet you’ll get it replaced free of charge.
Q:Can you fire it left handed or does the cocking handle move after every round? Why I ask is cause the British SA 80 has a similar cocking handle design and it cannot be fired lefty. The handle smacks you in the teeth, trust me I know from experience.
A: Yes, the AR18 and SA80 operating systems are extremely alike. The SA80 is, for the most part, copied from the AR18 operating system. That being said, the SA80 is a bullpup, putting the action right next to your face. The AR180B is not. If you are getting a bolt handle in the face, you're doing something completely wrong.
Q: I'm a lefty, can I change the safety to the other side?
A: No, you can't just flip the factory safety around to the other side. Armalite does offer an ambidextrous safety as an after-market part. I've also seen home built mods where the stock safety was drilled and tapped on the right side and the end of an AR15 safety was screwed in to make a home made ambi-safety.
Q: What is the classification of the AR180B?
A: Being that the AR180B is a new rifle it classification is based on barrel length. As it is a semi-auto center fire the barrel length must be over 18.5” for the rifle to be non-restricted. There are currently 2 version of the AR180B. The integral muzzle brake version which came out during the United States “Assault Weapons Ban” days is non-restricted. After the sunset of the Assault Weapons Ban a version with a factory threaded barrel was introduced, this version is restricted due to barrel length.
Q: Isn’t the AR180B a variant of the prohibited AR180, how can it be non-restricted?
A: You’re trying to use logic to explain Canadian Firearms law, it won’t work. Now sit back and enjoy, this explanation is long and confusing. The reason the AR180B is not classed as a variant of the prohibited AR180 is due to some major operating changes. In Canada, a variant is determined by a few items, one being the operating system or action. As the AR180B uses an AR15 type trigger group, it is not an AR180 variant in that respect. It also uses AR15 magazines, another notch for not being an AR180 variant. By this logic it could be called an AR15 variant but then the action and receiver comes into play. The AR180B is gas operated using a short stroke piston, a completely different recoil system (i.e.: no buffer tube), and an entirely different receiver. So now we look at it and say, “It’s not an AR180 variant and it’s not an AR15 variant. Therefore, it must be a new type of rifle.” Bingo. Now we look at the barrel length, low and behold it’s long enough to be non-restricted.
Q: That was confusing, how do you understand Canadian Firearms law?
A: No one understands Canadian Firearms law, we just try to understand how small parts of it work. Mostly we bulls**t our way through it.
Q: I love the AR15 but want a non-restricted version, is the AR180B a good choice?
A: The Armalite AR180B is NOT an AR15 type rifle. If you purchase it thinking that you are getting a non-restricted AR15, you will be disappointed. The AR18 was designed as a cheaper option to the AR15. It was sheet metal construction with a bolt carrier system that allowed for huge tolerances in manufacturing. It is not an AR15 by any stretch of the imagination.
Now I Own One: Let’s make it function flawlessly
Q: My rifle fires and ejects but fails to load a fresh round. If I cycle the bolt manually, the rounds load just fine.
A: Check your gas block. If it is misaligned, or to far forward or back, this could restrict gas flow to the piston. The rifle will fire and eject rounds but the piston won't have enough power to push the bolt back far enough to chamber a fresh round.
Q: My firing pin is stuck forward, what do I do?
A: Sometimes the hammer hitting the firing pin will deform the bolt carrier around the firing pin. The hole that the firing pin goes into will become peened around the firing pin. This is solved by simply file a chamfer around the edge of the hole.
Q: Some of my magazines don’t feed. How do I make my rifle feed reliably?
A: My rifle is one of the earlier models and suffered some feeding issues. This was quickly fixed by filing a ramp on the front of the magazine. This did not fix the problem for all magazine. Applying a small bit of epoxy to the trigger guard did. My rifle functions flawlessly for the past 4 years.
From personal experience and from talking with others I've found that Colt magazines are the worst performers in the AR180B. With the epoxy fix they function flawlessly.
New fix: CGN member G37 has come up with a better, more esthetically pleasing fix for the feeding issue. However, it requires cutting your rifle. Basically, he cut M4 feed ramps into his barrel nut and front receiver trunnion.
Update: From talking with owners of new rifles it now looks like Armalite is adding the "M4 Style" feed ramps to new rifles straight from the factory. This should solve all feeding and magazine issues.
Q:I've removed and reinstalled my gas block for ### reason, now my rifle doesn't eject spent rounds consistently or does not eject at all.
A: Your gas block is cockeyed and this is causing the hole in the barrel and the hole in the gas block to not line up, restricting gas flow and preventing enough power to cycle the bolt. If you do not have the stock hand guards installed, the gas block may be too far back on the barrel and that is cutting off the gas ports. You'll notice that when you have the stock hand guard installed the gas block is not tight against that little collar on the barrel. Install it a little further forward with a bit of a gap between the collar and the rear of the gas block. I think mine is about 2 mm or so. It's not precise, just eyeball it
Important Notice!
Be sure your gas block is on straight! It has come to my attention that cockeyed gas blocks will lead to excessive wear on one side of the gas piston.
Q: What parts are interchangeable between the AR180B and the AR15?
A: The trigger group (minus the safety selector), the mag catch, front and rear site components, ejector, extractor, probably some springs. That’s it.
Q: What kind of groups can I expect with my rifle?
A: From personal experience and from what I’ve been told by other users, 1 to 2.5 inch groups at 100 yards with factory ammo and irons is easily attainable by a competent shooter. Add some optics, hand loaded ammunition, and you could shrink that group down. I’ve been told as little as .5 to 1 inch groups, if not smaller.
Q: Speaking of optics, how do I mount a scope?
A: You will have to buy a scope base for your rifle. When I first got mine, this was easier said than done. Now days we are lucky as there are numerous options to choose from. I’d list them all but that would be wasting your time. When it comes to scope bases there is only one choice: www.stormwerkz.com.
Josh Miller of Storm Werkz does amazing work. He also has amazing customer service and deals with Canadians all the time. Storm Werkz ships to Canada with no issues what so ever. Place your order and wait in confidence. Great prices, great service, and fast shipping. No, I am not paid by Josh, I am just a very happy customer. However, I think I'd should be getting paid for all the promotion I do!
Can I put on folding sites?
In short, no. The AR180B site line is much lower than the AR15. To add AR15 flip up sites you would have to remove the rear site and install a full length rail on the receiver. You would then need to design and manufacture a railed gasblock, or a gasblock with an integral folding sight. If you manage this, your folding rear site will probably sit just as high as the stock rear site even when folded down, thus negating any reasoning behind doing all that work.
Q: What about railed hand guards?
A: Again, when I first got my rifle there was not much for accessories. I’d even hazard to say I pioneered the use of railed hand guards on the AR180B (just tootin' my own horn). Thankfully for you, spending over $600 to custom mount an AR15 railed hand guard won’t be necessary. Midwest Industries now offers a drop in railed hand guard that replaces the factory hand guards.
Midwest Industries railed hand guard
Minor modification is needed as the user must cut ¼” off the front of the recoil spring guide rods. Five minutes work with a Dremel or hacksaw. You can purchase that MI railed hand guards from Wolverine Supplies.
Q: I want a folding/M4/skeletal stock on my AR180B. How do I do this?
A: First you will need a stock adapter. All adapters on the market require you to permanently modify your receiver and usually mean you can not return to the factory stock. Trust me, you won’t be going back.
Again there are a few companies that offer these adapters but this author only has one suggestion. Storm Werkz offers three types of adapters. Check their site for pictures and info.
Q: Can I do anything about the trigger?
A: You sure can. As the AR180B uses standard AR15 trigger parts, however the pins are longer. You can swap out the trigger with any after market AR15 trigger group. Simple as that.
Q: Can I change the grip?
A: Not easily. The grip is molded into the polymer lower receiver and is all one piece. I’m sure it could be done but I don’t know if it would be worth the trouble and possibly ruining your receiver.
Q: Can I put a different or AR15 barrel on the AR180B?
A: Sure, you could have a custom barrel made up but that would probably cost the same if not more than the complete rifle.
The AR15 barrels and AR180B barrels have the same threads. One could theoretically thread an AR15 barrel into the AR180B barrel trunnion. Setting the head spacing would be required and the gas hole would not line up. It may be possible to make an AR15 barrel work if the gas hole was drilled specifically for the AR180B.
There is play between the upper and lower receiver, is this normal?
Yup, perfectly normal and has no affect on accuracy. If, however, you wish to remedy this purely cosmetic issue, it is simple. Grab a pair of pliers with soft jaws and slightly bend in the back portions of the upper receiver so they more tightly hold the recoil spring guide rod assembly. Don't over do it, bend tiny bits at a time!
The Other Stuff
Q: How easy is it to convert the AR180B to full auto?
A: It’s impossible as that is illegal.
Q: How do I remove the barrel?
A: You will need a barrel extension wrench. You can make your own from an old/broken AR15 bolt or you can buy one here (it will have to be modified): http://www.brownells.com/aspx/NS/store/productdetail.aspx?p=12729&s=
To remove the barrel on an AR-180B: strip everything off the upper including the front sight base, make a reference mark on the barrel and the upper receiver for realignment on reinstall, clamp the barrel in a good vise with barrel blocks, then with either a purchased or home made barrel extension wrench turn the receiver/barrel extension off the barrel. Counter clockwise, they are standard right hand threads. DO NOT try to turn the receiver by itself, you will just spin the barrel extension out of alignment with the receiver. Remember, you are turning the entire receiver off the barrel, not the barrel off the receiver.
Q: Does any one make an aluminum or sheet metal lower like the original?
A: Not at the moment. There have been numerous home built replacement receivers as well as rumors of Armalite bringing out a whole new rifle with a machined lower. This has yet to materialize.
Q: What is your area of expertise that makes you qualified to write this FAQ?
A: I've owned an AR180B for many years and have done numerous mods to it. That's my qualification. Also, I'm a big deal on the internet.
Thanks to:
Josh Miller of www.stormwerkz.com,
And every one who has pestered me with questions over the years.
Last edited:
strip everything off the upper including the front sight base, make a reference mark on the barrel and the upper reciever for realignment on reinstall, clamp the barrel in a good vise with barrel blocks, then with either a purchased or home made barrel extension wrench turn the reciever/barrel extension off the barrel. counter clock wise, they are standard right hand threads. DO NOT try to turn the reciever by itself, you will just spin the barrel extension out of alignment with the reciever.
