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What is 450 Bushmaster upper? 🤔

It is part of an AR-15 rifle’s upper receiver. It is part of the rifle that houses and provides support for most of the components necessary for firing, such as the bolt carrier group, charging handle, and forward assist.

450 Bushmaster upper

Features 😎

  • ☑️ Caliber: This upper is chambered in the .450 Bushmaster cartridge. This powerful round was specifically designed for big game hunting, making it one of the best options for hunting large animals such as elk or bears.
  • ☑️ Barrel Length: A typical 450 Bushmaster upper will have a barrel length between 16 and 20 inches. The length of the barrel affects both accuracy and velocity, with longer barrels offering increased accuracy and higher velocities.
  • ☑️ Muzzle Device: A muzzle brake or flash suppressor is a common feature on it. The muzzle brake reduces recoil, making it easier to stay on target, while the flash suppressor reduces the bright flash of light that occurs when firing the weapon.
  • ☑️ Handguard: A free-floating handguard is often used with such uppers. This type of handguard attaches to the receiver and does not touch the barrel, resulting in improved accuracy. It also provides space for mounting accessories like lights, lasers, and bipods.
  • ☑️ Bolt Carrier Group: The bolt carrier group is the heart of the upper receiver, operating the action and feeding rounds into the chamber. It is built to handle the high energy of the .450 Bushmaster round, ensuring reliable performance.
  • ☑️ Charging Handle: The charging handle is used to manually cycle the bolt carrier group, allowing for the chamber to be cleared, the firearm to be unloaded, or a round to be loaded directly into the chamber.
Our Top Pick
GLFA AR-15 Complete Upper
Crafted by industry pioneers, these upper receivers feature an A3 flattop upper receiver with M4 feed ramps that ensure optimal control during shooting. The use of premium materials, such as the 18-inch chrome moly barrel, results in a precision-machined product that is unbeatable in quality and durability. With its outstanding components, this upper receiver promises a longer lifespan for your firearm. It is the ultimate solution for eliminating hogs, boars, and other varmints with ease.
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Benefits 🔥

The 450 Bushmaster upper is a popular choice for hunters and shooters who want a powerful and dependable rifle. Here are some of the benefits:

  • ✳️ Power – It is known for its power. It can deliver up to 4,000 foot-pounds of energy, making it a great choice for hunting big game. The upper’s powerful design can take down large animals such as deer or bear with ease.
  • ✳️ Accuracy – This upper is remarkably accurate, thanks in part to its flat trajectory, which allows for better accuracy and precision than some other rifle calibers. This, combined with the right scope, can provide hunters with a more significant advantage when it comes to lining up the perfect shot.
  • ✳️ Availability – The 450 Bushmaster ammunition is widely available, making it an excellent choice for gun owners who want a reliable and affordable ammo option.
  • ✳️ Recoil – The lower recoil makes it much easier to shoot and provides immediate follow-up shots, increasing the chances of successfully taking down a game animal.
  • ✳️ Easy to Use – Such an upper is easy to install onto an AR-15 lower, removing the need to purchase an entirely new firearm. It uses the same bolt carrier group and magazine as an AR-15, making it a versatile option for hunters and shooters.

The 450 Bushmaster upper

Major components 💡

The major components of a 450 Bushmaster upper assembly are the barrel, the receiver, the hand guard, and the muzzle device.

  • 🔶 The barrel is responsible for providing the power to send projectiles out at high velocities and must be made from high-grade materials to ensure accuracy and performance.
  • 🔶 The receiver houses all other components of the assembly and should be made from durable materials.
  • 🔶 The hand guard helps protect the shooter’s hands and provides some level of control while firing.
  • 🔶 Lastly, the muzzle device helps direct gas away from the shooter, ensuring a safe shooting experience.

🔍 When choosing an upper receiver, it is important to consider all of these components carefully.

  • ✍️ A good quality barrel should have an appropriate twist rate (twist rate is the amount of spin given to each bullet when fired) and length for the desired caliber and range you are looking for in your rifle.
  • ✍️ Additionally, receivers must also be able to fit standard parts such as stocks, triggers, etc., as well as specific components like barrels from other manufacturers.
  • ✍️ When selecting a hand guard, you need to assess the type of material used, as well as its design and length.
  • ✍️ Lastly, a muzzle device should be chosen based on personal preferences and what type of shooting you plan to do.

Our Selection 11 Best 🚀 450 Bushmaster Upper

ImageProductBrand
Radical Firearms Complete Upper .450 BushmasterRadical Firearms Complete Upper .450 BushmasterRadical FirearmsBUY
Failzero Fail Zero Bolt Carrier Group .450 Bushmaster Ar-15Failzero Fail Zero Bolt Carrier Group .450 Bushmaster Ar-15FailzeroBUY
GLFA AR-15 Complete Upper .450 Bushmaster LJ450BUSHSSGLFA AR-15 Complete Upper .450 Bushmaster LJ450BUSHSSGLFABUY
Brenton USA Stalker Carbon Hunter .450 Bushmaster Upper ReceiverBrenton USA Stalker Carbon Hunter .450 Bushmaster Upper ReceiverBrenton USABUY
GLFA AR-15 Complete Upper .450 Bushmaster LJ450BUSHGLFA AR-15 Complete Upper .450 Bushmaster LJ450BUSHGLFABUY
Wilson Combat Upper ReceiverWilson Combat Upper ReceiverWilson CombatBUY
Glfa Ar-15 Complete Upper .450 Bushmaster LJ450BUSHKGlfa Ar-15 Complete Upper .450 Bushmaster LJ450BUSHKGlfaBUY
Brenton USA Ranger Carbon Hunter .450 Bushmaster Upper ReceiverBrenton USA Ranger Carbon Hunter .450 Bushmaster Upper ReceiverBrenton USABUY
Radical Firearms 450 MHR Complete Upper ReceiverRadical Firearms 450 MHR Complete Upper ReceiverRadical FirearmsBUY
Next Level Armament 450 Bushmaster Complete Upper NLX501Next Level Armament 450 Bushmaster Complete Upper NLX501Next Level ArmamentBUY
American Tactical Imports AR-15 Complete UpperAmerican Tactical Imports AR-15 Complete UpperAmerican Tactical ImportsBUY

1# Radical Firearms Complete Upper Assembly

Radical Firearms Complete Upper .450 Bushmaster

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Specification

Caliber: .450 Bushmaster
Barrel Twist Rate: 1-14
Handguard Style: Hybrid Rail

Do you worry about assembling various parts or wasting time? The Radical Firearms Complete Upper Assembly is already assembled and comes complete with an upper receiver, forward assist, custom ejection port door, barrel nut, 16-inch barrel, Panzer muzzle brake, bolt carrier group, charging handle, and a mag. Our research has shown that it includes M-Lok attachment points on the sides and bottom, as well as Picatinny rails at the fore-end, so you can use these attachment points to mount accessories such as optics, lasers, lights, bipods, and more, to customize your rifle to its fullest potential. Get your Radical Firearms Complete Upper Assembly today!

Pros
  • Comes fully assembled
  • Features M-Lok attachment points on the sides and bottom
  • Picatinny rails at fore-end
  • Incredible value
Cons
  • Muzzle brake can be loud
  • Only suitable for AR-15s with a standard barrel nut thread pitch

 

2# Failzero Fail Zero Bolt Carrier Group

Failzero Fail Zero Bolt Carrier Group .450 Bushmaster Ar-15

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Specification

Caliber: .450 Bushmaster
Gun Model: AR-15

Searching for a top-quality bolt carrier group that is built to last? Notice the Failzero Fail Zero Bolt Carrier Group. Designed with durability and reliability in mind, this bolt carrier group is crafted from high-quality materials that are built to withstand the test of time. With its top-notch construction and materials, this bolt carrier group is an excellent choice for anyone who needs a high-performance product that will deliver reliable performance for years to come.

Pros
  • High-quality construction and materials
  • Crafted for reliability and durability
  • High-performance
  • Durable
Cons
  • Not currently available in other calibers
  • May be a bit expensive for some budgets

 

3# GLFA AR-15 .450 Bushmaster Complete Upper

GLFA AR-15 Complete Upper .450 Bushmaster LJ450BUSHSS

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Specification

Caliber: .450 Bushmaster
Gun Model: AR-15
Handguard Length: 15 in
Barrel Length: 18 in
Weight: about 6lbs

Do you want to experience easy mounting of optics and accessories? Try the GLFA AR-15 .450 Bushmaster Complete Upper which features a floating M-Lok handguard. Manufactured from stainless steel, these upper boast a distinctive appearance and superb accuracy. It comes with a big-bore stainless steel muzzle brake installed, ensuring that you stay on target. Our analysis of this product showed that equipped with an A3 upper and M4 feed ramps, the 15-in floating M-Lok handguard makes for a reliable and comfortable shooting experience. Elevate your hunting rifle’s performance and install the GLFA AR-15 .450 Bushmaster Complete Upper today.

Pros
  • Made from stainless steel
  • Superior accuracy and strength
  • Features an A3 upper receiver with M4 feed ramps
  • Equipped with a 15-inch floating M-Lok handguard
Cons
  • Not compatible with older versions of A2 upper receivers
  • Not suitable for lighter builds due to its heavier weight

 

4# Brenton USA Stalker Carbon Hunter 18-Inch .450 Bushmaster Upper Receiver

Brenton USA Stalker Carbon Hunter .450 Bushmaster Upper Receiver

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Specification

Caliber: .450 Bushmaster
Overall Length: 25.375 in
Barrel Length: 18 in
Gas Block Journal Size-Diameter: .875 in
Handguard Length: 13.5 in
Gun Model: Brenton Stalker Carbon Hunter
Weight: 2.06 lb

As a hunter, you know that time in the field is precious, and the competition for trophy opportunities is fierce. That’s why you need a hunting rig that’s rugged, reliable, and quick to handle. And with Brenton USA Stalker Carbon Hunter 18-Inch .450 Bushmaster Upper Receiver, you can have absolute confidence in your equipment. Built for hunters by hunters, these uppers are offered in a wide variety of big game and varmint hunting chambers and are guaranteed for life. With no hype or nonsense, Brenton products deliver the look, feel, and performance demanded by serious hunters. So hunt with confidence, and hunt with Brenton.

Pros
  • HuntSpec materials manufacturing processes
  • Reliable construction
  • Quick handling design for accuracy in the field
  • Lifetime guarantee on all components
Cons
  • The price point is higher than other models
  • No customization options

 

5# GLFA AR-15 .450 Bushmaster Complete Upper

GLFA AR-15 Complete Upper .450 Bushmaster LJ450BUSH

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Specification

Caliber: .450 Bushmaster
Gun Model: AR-15
Barrel Length: 18in

If you want to elevate your precision shooting game, notice the GLFA AR-15 .450 Bushmaster Complete Upper. This upper receiver from GLFA boasts an A3 flattop upper with M4 feed ramps, allowing for greater control while shooting. Precision machined from top-quality materials like the 18-inch chrome moly barrel, this upper receiver is built to last. Say goodbye to pesky varmints with this upper assembly, designed to eradicate hogs, boars, and other games with ease. Trust in the exceptional quality and durability of the GLFA AR-15 .450 Bushmaster Complete Upper for your next hunting excursion or precision shooting competition.

Pros
  • 18-inch chrome moly barrel for superior precision
  • A3 flattop upper with M4 feed ramps
  • Compatible with all standard .450 Bushmaster magazines
  • Excellent choice for hunting hogs, boars
Cons
  • Does not come with a gas block or gas tube
  • Not suitable for left-handed shooters

 

6# Wilson Combat Upper Receiver

Wilson Combat Upper Receiver

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Specification

Caliber: 5.56x45mm NATO, .458 SOCOM
Gun Model: AR-15

When it comes to building your AR-15, the upper receiver is where quality begins. Pay attention to the Wilson Combat Upper Receiver for the ultimate in durability and performance. Crafted from 7075-T6 forgings machined to Mil-Spec Plus tolerances, this receiver is made to last. Its rugged black hard coat anodized finish offers superior protection against wear and tear. Featuring M4 style feed ramps and a Picatinny top accessory/optic rail, it is a must-have for any AR-15 build. Choose Wilson Combat for the best in AR-15 upper receivers!

Pros
  • Mil-Spec Plus tolerances for superior durability
  • Hard coat anodized finish
  • Optimal protection against wear and tear
  • Reliability with most magazines
Cons
  • Not compatible with all AR-15 components
  • Not available in different colors

 

7# GLFA AR-15 .450 Bushmaster Keymod Complete Upper

Glfa Ar-15 Complete Upper .450 Bushmaster LJ450BUSHK

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Specification

Caliber: .450 Bushmaster
Barrel Length: 18 in
Barrel Twist Rate: 1-24
Gun Model: AR-15

Introducing the GLFA AR-15 .450 Bushmaster Keymod Complete Upper with an 18″ Keymod handguard – is designed to be an exceptional product suitable for anyone. Our findings show that it is crafted from robust and durable materials, and this upper receiver is built to provide reliable performance for many years to come. With a proven track record of producing high-quality products, GLFA showcases its commitment to excellence with the GLFA AR-15 .450 Bushmaster Keymod Complete Upper – try it today!

Pros
  • Comes with an 18″ Keymod handguard
  • Uses durable materials to ensure long-term reliability
  • Compatible with standard AR15 components
Cons
  • May require custom tools for installation and assembly

 

8# Brenton USA Ranger Carbon Hunter 22-Inch .450 Bushmaster Upper Receiver

Brenton USA Ranger Carbon Hunter .450 Bushmaster Upper Receiver

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Specification

Caliber: .450 Bushmaster
Overall Length: 29.375 in
Barrel Length: 22 in
Barrel Profile: Medium Hunter
Gas Block Journal Size-Diameter: .875 in
Barrel Twist Rate: 1-24
Handguard Length: 15 in
Weight: 2.38 lb

Choosing the right upper receiver can be overwhelming due to the wide range of options available. Check out the Brenton USA Ranger Carbon Hunter 22-Inch .450 Bushmaster Upper Receiver is a durable option that comes with a medium profile barrel finished with black nitride, a versatile forearm with dual-sided carbon fiber texture, and an ambidextrous trigger reach. By selecting this upper receiver, you can customize a reliable and versatile hunting rifle that meets all your needs.

Pros
  • Ambidextrous trigger reach
  • Long-lasting 5-round hunting magazine
  • Comes with a bi-pod/sling mount and a tripod mount
  • Easy installation and maintenance
Cons
  • Not ideal for small-game hunting
  • High price tag

 

9# Radical Firearms 450 MHR Complete Upper Receiver Group

Radical Firearms 450 MHR Complete Upper Receiver

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Specification

Caliber: .450 Bushmaster
Barrel Length: 16 in
Gas System Length: Pistol Length
Handguard Length: 7 in

Searching for an exceptional upper receiver for your AR-15? The Radical Firearms 450 MHR Complete Upper Receiver Group is a top contender. Constructed using the strongest and most durable materials available, this upper receiver is built to last for years of reliable use. Whether you’re a seasoned shooter or just starting, this upper receiver is a great choice for anyone who wants to get a reliable and durable addition to their AR-15.

Pros
  • Constructed from high-quality materials
  • Designed with precision for a secure fit
  • Comes with a mil-spec upper receiver assembly
  • Including forward assist and dust cover
Cons
  • The barrel and gas tube are not included
  • Installation may require additional tools or supplies

 

10# Next Level Armament 450 Bushmaster Complete Upper

Next Level Armament 450 Bushmaster Complete Upper NLX501

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Specification

Caliber: .450 Bushmaster
Handguard Length: 13 in
Handguard Type: Free-Float
Threads per Inch: 11/16×24

Transform your AR15 into a powerful hunting tool with the Next Level Armament 450 Bushmaster Complete Upper! It was designed with top-quality components to meet the growing demand for the 450 Bushmaster round. As a result of our tests, we determined that it has a superior design and offers incredible accuracy, and ranges from a large caliber bullet. This complete upper receiver comes with all the upgrades standard, so why settle for inferior parts and pay more to upgrade later? Invest in the Next Level Armament 450 Bushmaster Complete Upper and take your hunting game to the next level!

Pros
  • Aerospace-grade machining and aluminum for maximum durability
  • Reliability and effectiveness range from a large caliber bullet
  • Superior design with all upgrades
Cons
  • Not available in different colors
  • Not suitable for tactical use

 

11# American Tactical Imports AR-15 Complete Upper

American Tactical Imports AR-15 Complete Upper

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Specification

Caliber: .450 Bushmaster
Barrel Length: 16 in
Handguard Length: 15 in

Do you want to buy a 450 Bushmaster caliber upper receiver? Check out the top-quality option featuring a 16-inch barrel with a 1:24 twist rate, a 15-inch Keymod rail, and a 5/8×32 flash hider. American Tactical Imports AR-15 Complete Upper ensures reliable performance and long-lasting durability. Trust in superior craftsmanship and attention to detail for a top-notch upper receiver that won’t let you down!

Pros
  • 16-inch barrel with a 1:24 twist rate
  • 15-inch Keymod rail for customization
  • Superior nitride bolt carrier group
  • Flash hider included
Cons
  • No sights or scope included
  • Must be purchased through a licensed firearms dealer

 

🛠️How to build (assemble) it?🛠️

Building a 450 Bushmaster upper receiver is not as complicated as it sounds. For starters, you will need the following components: an upper receiver, a barrel assembly, front and rear sights or scope, a bolt carrier group, a charging handle, and other parts.

⤵️ Once you have all the necessary components to build your upper receiver, get started:

  • 📝 Step 1 – Start with the barrel assembly first. This is done by securing it into the upper receiver with two screws or pins, depending on the model. Make sure that the barrel lines up with the gas tube opening on top of the receiver as well as all other components.
  • 📝 Step 2 – Install the charging handle and bolt carrier group (BCG). For this step, use anti-seize lubricant or grease to make sure these parts function correctly without any issues. Also, make sure that your BCG fits correctly and doesn’t wobble when inserted in your upper receiver.
  • 📝 Step 3 – Install front sight post and rear sight or scope. This step is important for accurate aim and is generally done with the help of a gunsmith. Use an Allen key to secure the sights in place and make sure that they are perfectly aligned.
  • 📝 Step 4 – Finally, attach your upper receiver to the lower receiver group by tightening two pins at the front and rear of both receivers. Make sure not to over-tighten them as it may cause damage to both components.

😉 Once you’ve completed these steps, your upper receiver is now ready to go!

FAQ 🧐

What is included in a complete upper receiver?

➡️ A completed upper consists of the ejection port door and the installed forward assist button.

⚙️ Complete upper assemblies come with the barrel, charging handle, and handguard, and frequently with the bolt carrier group.

Do you need a special upper for 450 bushmasters?

😉 The 450 Bushmaster works with standard AR15 lowers and parts.

🔥 It is simple to make an AR build with this upper receiver, just purchase a complete upper and mags that compensate for the suboptimal Bushmaster case design.

How many yards is a 450 Bushmaster good for?

🎯 According to the shooters’ and hunters’ experience, the most effective distance for the 450 Bushmaster is around 250-to-300 yards.

🤠 It is enough for most medium-sized games.

How bad is the recoil on a 450 Bushmaster?

💣 The recoil power for the .450 will depend on the gun weight, it can vary between 15 and 20 ft-lbs.

🧑‍🔧 To make these figures clear, let’s compare them, for instance, a 3-inch 20 gauge rattles at 30 ft-lbs, and a 44 mag has 11 ft-lbs.

Does the 450 Bushmaster kick?

💡 The .450 Bushmaster is developed to work with AR-15 rifles.

⭕ The factory load generates nearly 23 ft-lbs of recoil, and a full-power 12-gauge bullet spawns 45 ft-lbs.

How much does a 450 Bushmaster drop at 200 yards?

📝 The .450 Bushmaster delivers a rather flat path out to 200 yards.

📌 Zeroed rifles at 150 yards can provide a rise of 1.8 inches at 100 yards and a 4.9-inch expected drop at 200 yards.

Conclusion 😊

Finding the best 450 Bushmaster upper for your needs can be a daunting task. With so many options on the market, it’s important to do your research and understand what features are most important for you. We hope this guide has provided helpful information that will make shopping for an upper easier and more enjoyable. Whether you’re searching for something with top-of-the-line accuracy or just want an affordable option without sacrificing too much quality, we think there you had found something just for your needs. Happy hunting! 🤠👍

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Jonathan Lopez
Jonathan Lopez
8 months ago

I have a couple of lowers that have been lying around and I’m thinking of building a 450 Bushmaster rifle for deer hunting in Ohio. It seems like there are only two extremes in terms of price – around $300 for questionable quality or $600 for higher quality. I’m wondering if any mid-range options are decent, or if it’s worth investing more money for better quality.

Wandie
Wandie
Reply to  Jonathan Lopez
8 months ago

I think that American Tactical Imports AR-15 Complete Upper is a good option, but unfortunately, most manufacturers of 450 uppers are not very good. So it might be worth doing some research and paying a little more for a better-quality option.

Noam Patterson
Noam Patterson
Reply to  Jonathan Lopez
8 months ago

I know of a couple of companies that manufacture 450 uppers such as Radical Firearms and Wilson. However, I’m planning on building my own using a Faxon barrel and purchasing the other components separately.

Enitara
Enitara
8 months ago

Hello everyone, I recently found out that hunting in Michigan requires the use of straight wall cartridges, and it seems like the .450 Bushmaster is a popular choice among hunters in the area. I am interested in purchasing a complete rifle or putting together my own using a complete upper and assembling my own lower. But I am having trouble finding a good quality upper or complete rifle. Can anyone recommend where I can find what I am looking for? Thank you in advance!

Rex White
Rex White
Reply to  Enitara
8 months ago

I use Radical Firearms 450 MHR Complete Upper Receiver with Hornady Black 250gr FTX ammunition. So far, I haven’t had any issues with it blowing up and it’s surprisingly lightweight for long walks in the mountains of Idaho.

Ganakinf
Ganakinf
Reply to  Enitara
8 months ago

I know a good option for building a 450 Bushmaster rifle. Wilson Combat Upper Receiver will be useful for your needs.

Moses Wilson
Moses Wilson
8 months ago

I recently installed a side-charging 16-inch 450 Bushmaster upper on my lower that has worked fine for my 300 blackout uppers. However, when I tried shooting it with a stiff spring and heavy buffer, the gun wouldn’t cycle. It ejects the case and resets the trigger, but it doesn’t get another round or lock back on an empty magazine. Even after changing the buffer to a normal buffer and normal spring, I faced the same problem. I also removed the gas block and checked it, and it seems fine. The gas tube isn’t clogged, and it goes far enough into the receiver. From what I can tell, it seems like the gun isn’t getting enough gas, which is why it’s not locking back. Should I consider drilling the gas hole bigger or look for some other possible cause? I’m not sure what to check, so any advice would be appreciated. Thank you.

Tonice
Tonice
Reply to  Moses Wilson
8 months ago

As someone who works at a range, I come across issues like this frequently, and most of the time the solution is as easy as lubricating the bolt where it sits in the carrier. All you need to do is apply plenty of oil and manipulate it until it unlocks with a flick of the wrist. After that, put it back in the upper and it should cycle without any issues. You might experience some oil spray during the first few rounds, but any excess oil will either work its way onto the carrier or out of the rifle. It’s always better to run an AR over-oiled than under-oiled, as they function better when they’re well lubricated.

Quinnten Howard
Quinnten Howard
Reply to  Moses Wilson
8 months ago

Based on my experience with a similar issue on my first 6.8 SPC upper, it sounds like your rifle is short stroking. Even though it shoots and cycles fine, it occasionally fails to pick up the next round from the magazine or lock back on the last round. I’ve gone through the same process of checking and tinkering with the gas tube, key, magazines, buffer, and spring, but what ultimately fixed my issue was a simple fix of oiling the inside of the buffer tube. After oiling, my rifle ran smoothly, and once it was broken in, I haven’t had to re-oil the tube. I recommend you give this a try.

Zaru
Zaru
8 months ago

After starting my search for a new slug shotgun, I’m leaning towards a straight wall cartridge rifle for hunting as it’s now legal in Iowa. I already have an AR build and I’m thinking of buying a .450 Bushmaster upper. What do you suggest?

Yousuf Wood
Yousuf Wood
Reply to  Zaru
8 months ago

I find the .450 Bushmaster to be a very enjoyable cartridge to shoot. I have the American Tactical Imports AR-15 Complete Upper and have encountered no significant issues aside from needing to make sure the bolt slams forward to load the first round.