Best AR-15 Gas Blocks for 2017: The 13 Best Gas Blocks Reviewed

It doesn’t matter how awesome your AR-15 build is, if you pair it with a cheap gas block you’re asking for trouble. I’ve rated & reviewed 13 of the best AR-15 gas blocks available so that you don’t make the mistake of choosing a cheap, low-quality part.

Make Type Material Rating
TOP PICK
Geissele Gas Block Geissele Automatics Low Profile Stainless Steel 9.6/10

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LOW PROFILE
VLTOR Gas Block VLTOR Low Profile Carbon Steel 9.5/10

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ADJUSTABLE
Odin Works Adjustable Gas Block

Odin Works Adjustable Carbon Steel 9.5/10

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TITANIUM
Battle Arms Development Titanium Gas Block Battle Arms Development Low Profile Titanium 9.4/10

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PICATINNY
JP Enterprises Gas Block JP Enterprises Picatinny Carbon Steel 9.4/10

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I admit it, my first AR-15 build wasn’t the rousing success I hoped for. And by that, I mean it barely worked at all.

The problem, as it turns out, was a no-name gas block I picked up for cheap. I was bleeding too much gas at the barrel leaving little pressure to cycle the action. To put it another way, there was not enough energy left to reliably eject and chamber a new round. Pretty embarrassing.

Fortunately, I was able to fix the problem by installing a new, high-quality gas block. But, it took several frustrating hours at the range to nail down the issue in the first place.

It was a hard lesson to learn, and now I pay close attention to every gas system component I put on my rifles – and you should too. I’m willing to shell out a few extra dollars for a great gas block knowing my weapon will be reliable day in, day out.

Rest assured, there are a ton of awesome, precision machined gas blocks on the market that will preempt any fitment issues like the one I had. I’ve even created this buying guide to help you find the right one.

Best Low Profile Gas Block

Geissele Gas Block

Low profile gas blocks are compact and made to fit under long free float handguards. They can also replace A2-style front sights if you are transitioning away from traditional drop-in handguards.

The gas block is subjected to a tremendous amount of heat and stress. As such, it needs to be built with durable materials and finishes so that it can withstand the abuse. This is even more crucial for low profile gas blocks.

Since they are made with less material, and, therefore, have less mass, any imperfection or weakness in the medium can cause the gas block to fail prematurely. Because of constant heat cycling, cracks may rapidly propagate in inferior materials, for example. This can cause your gas block to come loose or break.

Right now, there are a lot of great low profile gas block options on the market – the five (5) listed below represent some of the best. They are all precisely machined from high-quality stainless or carbon steel and feature tough finishes like phosphate and nitride.

They’re also produced by reputable companies that stand behind their products. This means high quality control standards, great customer service, and liberal return policies if something does go wrong. So, if you’re looking for a simple, rock-solid gas block, then one of these will suit you well.

Top Low Profile Gas Blocks Compared (Click ‘Read Review’ to Expand)

Geissele Gas Block Geissele Automatics
  • 9.6/10 Rating
  • Stainless Steel
  • Raw; Nitride
  • Low Profile
  • Non-Adjustable

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Geissele Gas Block

Recommendation

The Geissele Automatics Super Gas Block is perhaps the ultimate low profile, non-adjustable option for your AR-15. The solid design, construction, and built in barrel pinning provisions ensure ultimate toughness and bombproof stability.

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Tech Specs

Material Stainless Steel
Finish Raw or Nitride
Type Low Profile
Adjustable No

Geissele Automatics Super Gas Block

The Geissele Automatics Super Gas Block is easily one of the best all-around gas blocks on the market. No, it isn’t adjustable, but is expertly cast from durable 17-4 precipitation hardening stainless steel, which combines superior corrosion resistance with high strength.

Though, where it really stands out is the built in pilot hole, which allows you to pin the gas block to the barrel. This dramatically reduces the risk of slipping or moving, particularly if the weapon is going to be used in a duty or combat situation.

The gas block is available in either a raw or nitride finish and everything you need to install it is included with your purchase.

On top of the great features, this gas block comes in at a very competitive price point. You can find it for less than $50 from most online retailers, which is a great deal considering what you get.

Ultimately, the Geissele Super Gas Block is our top pick for builders who want the best price-to-performance ratio possible. If you need a rock solid and simple gas block, this is it.

VLTOR Gas Block VLTOR
  • 9.5/10 Rating
  • Stainless Steel
  • Phosphate; Raw
  • Low Profile
  • Non-Adjustable

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VLTOR Gas Block

Recommendation

The VLTOR gas block is precisely machined from high-quality 17-4 PH stainless steel and is available in both set screw and clamp on styles. This gas block is rugged, reliable, and light weight – very much inline with VLTOR’s reputation for building products that last.

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Tech Specs

Material Stainless Steel
Finish Raw or Phosphate
Type Low Profile
Adjustable No

VLTOR Gas Block

VLTOR is a well known producer of parts and accessories for the AR-15 platform and their low profile gas block is one of the best.

Construction wise, it’s made from very hard and corrosion resistant 17-4 PH Stainless Steel and is available with a phosphate or bead blasted matte finish.

It also has a reference hole that lets you precisely align the block with the gas port. Simply turn the gas block up side down and make your mark, then spin it around and line everything up. Tighten the set screws using a little Loctite and you’re good to go.

VLTOR also offers a clamp-on style gas block. Though they aren’t my cup of tea, some people prefer clamp-on gas blocks because they are a bit easier to install.

It’s possible you may have issues fitting the clamp-on style gas block under skinny rails due to the large bolts. So be sure to research whether this will fit under your handguard before making a purchase.

Regardless of the style you choose, this is a very high quality and extremely capable gas block.

Bravo Company Gas Block Bravo Company
  • 9.3/10 Rating
  • Carbon Steel
  • Phosphate
  • Low Profile
  • Non-Adjustable

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Bravo Company Gas Block

Recommendation

Made from carbon steel and featuring a phosphate finish, this gas block is dead simple and reliable – just like most Bravo Company accessories. If you’re looking for a solid, no-frills low profile gas block, this is an excellent option.

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Bravo Company Gas Block

Bravo Company is a top-tier manufacturer of AR-15 parts for both the civilian and military communities. Their products are known for quality and reliability, but they have to be considering the clientele.

Their gas block is certainly no exception to the rule. It is constructed from 4140 carbon steel and machined to excruciatingly tight tolerances.

As a bonus, it’s finish honed to guarantee a smooth bore, free from any high or low spots. Finally, a hard-wearing phosphate finish is applied and the Bravo Company logo is laser etched into the gas block.

Though spartan, this gas block reeks of quality and checks all the right boxes. Everything needed for installation comes in the package, including two (2) 10-32 x 3/16″ set screws and a roll pin for your gas tube.

Midwest Industries Micro Gas Block Midwest Industries
  • 9.2/10 Rating
  • Carbon Steel
  • Phosphate
  • Low Profile
  • Non-Adjustable

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Midwest Industries Micro Gas Block

Recommendation

There is a trend towards thinner, more streamlined handguards that require an ultra low profile gas block. The Midwest Industries Micro Gas Block is seriously small. If clearance is an issue for you, this may be what you’re looking for.

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Midwest Industries Micro Gas Block

Midwest industries is known for their high quality, but no frills parts and their Micro Gas Block fits the bill perfectly. Machined from tough 4140 carbon steel and finished with phosphate, this gas block is simple and reliable.

However, what really sets it apartfrom a lot of other blocks is its size. At just 1 1/8″ long and with a wall thickness of just 1/8″ in some parts, this thing is extremely compact. It’s ideal if you’re running a very slim profile handguard where you may have trouble fitting a more bulky gas block.

Overall, if you’re looking for a gas block that’s ultra small but tough, there really aren’t a lot of better options than this one from Midwest Industries.

Troy Industries Gas Block Side Troy Industries
  • 9.2/10 Rating
  • Carbon Steel
  • Phosphate
  • Low Profile
  • Non-Adjustable

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Troy Industries Gas Block Side

Recommendation

Simple, steadfast, and reliable is how I would describe this gas block from Troy Industries. This is another extremely compact part machined from top-shelf materials. It’s a great option for AR-15 builds where small size matters.

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Troy Industries Gas Block

This gas block protrudes only .420″ above the barrel, covers about 1″ of barrel length, and only adds 1.4 ounces of weight. Needless to say it is very compact and light weight.

It’s small profile means it won’t interfere with longer free float handguards, while insuring proper function of the gas system. It is obviously compatible with any gas system length and offers a clean, uncluttered look for your build.

Two hex head setscrews keep the gas block securely anchored to the barrel so it won’t shift during firing. To top it off, it is made in the USA and comes with an unconditional lifetime warranty. That’s great peace of mind.

Best Adjustable Gas Block

Odin Works Adjustable Gas Block

Adjustable gas blocks let you fine tune the amount and pressure of gases inside your gas system. The ability to make granular changes can dramatically affect the function and feel of your weapon overall. And, for AR-15 pistol or other short barrel applications, they’re almost a requirement.

Over-gassed setups like these tend to be very harsh, which, in some cases, leads to severe degradation and reduced lifespan of parts. By reducing the amount and pressure of gas you can smooth things out a bit, while maintaining enough energy to effectively cycle the action.

By coupling an adjustable gas block with other mods, like low mass bolt carrier groups and lighter buffer and buffer springs, you can see even more improvement. This is particularly useful for competition shooters where lighter felt recoil means faster target acquisition.

Many considerations are the same for adjustable gas block as they are with non-adjustable blocks. Things like high quality materials, finishes, and construction are paramount. Though, adjustable gas blocks require a bit more attention to detail to get right.

Things like ball detents and locking screws give you positive feed back and guarantee precise, stable adjustments. The three (3) adjustable gas blocks listed below represent the best available.

Top Adjustable Gas Blocks Compared (Click ‘Read Review’ to Expand)

Odin Works Adjustable Gas Block Odin Works
  • 9.5/10 Rating
  • Carbon Steel
  • Phosphate
  • Low Profile
  • Adjustable

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Odin Works Adjustable Gas Block

Recommendation

The Odin Works adjustable gas block is easy to use and infinitely adjustable. It’s feature packed, reliable, and cost effective. A lot of work and attention to detail has gone into making this gas block one of the best on the market.

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable Yes

Odin Works Adjustable Gas Block

Adjustable gas blocks let you adapt your weapon to different shooting conditions and loads. The problem with some, however, is it can be difficult to make adjustments in the fields and many even require you to remove the handguard first. But what if you need to make changes on the fly?

Odin Works designed their gas block so it can be tuned from the front by simply turning the adjustment screw with a hex key – so no need to remove the handguard itself.

Also great is how much adjustment you get and how stable it is overall. There are 20 clicks of ball detent adjustment available and no set screw is required to maintain the adjustment. Simply adjust the screw where you want it and you’re done.

This gas block is made from durable 4140 carbon steel and features a phosphate finish. It is only available in .750″ diameter but will work with any caliber round.

Odin Works Adjustable Gas Block

Seekins Precision
  • 9.3/10 Rating
  • Carbon Steel
  • Phosphate
  • Low Profile
  • Adjustable

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Recommendation

Learn More

Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Seekins Precision Adjustable Gas Block

Seekins Precision Adjustable Gas Block

Superlative Arms Adjustable Gas Block Superlative Arms
  • 9.3/10 Rating
  • Carbon Steel
  • Phosphate
  • Low Profile
  • Adjustable

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Superlative Arms Adjustable Gas Block

Recommendation

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Syrac Ordnance Adjustable Gas Block

Superlative Arms Adjustable Gas Block

Best Titanium Gas Block

Battle Arms Development Raw Titanium Gas Block

I’ve also included my picks for best titanium gas block. Titanium is exceptionally strong, light weight, and heat resistant, so it’s no wonder why it’s such a popular choice. Though, right now, selection is rather limited.

However, more and more manufacturers seem to be jumping on the titanium bandwagon and it’s just a matter of time before more options become available.

A low weight gas block reduces the overall weight of your weapon. Though, if I’m being honest, it doesn’t save you that much. A half ounce here and there isn’t going to make a huge difference. But I do understand many people like low weight builds, and this is just another tool in your box.

For me, the bigger benefit is from reduced weight at the end of the barrel. Removing weight from here effectively shifts the balance of your weapon towards your hands giving you more positive control. For some, this may affect practical accuracy and target acquisition time.

Whatever the reason why or regardless of whatever benefits you may find appealing, titanium gas blocks are an excellent option. The two (2) listed below represent the best of the bunch.

Top Titanium Blocks Compared (Click ‘Read Review’ to Expand)

Battle Arms Development Raw Titanium Gas Block Battle Arms Development
  • 9.4/10 Rating
  • Titanium
  • Raw or PVD
  • Low Profile
  • Non-Adjustable

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Battle Arms Development Raw Titanium Gas Block

Recommendation

Learn More

Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Battle Arms Development Titanium Gas Block

Battle Arms Development Raw Titanium Gas Block Battle Arms Development Titanium Gas Block

2A Armament Titanium Gas Block 2A Armament
  • 9.2/10 Rating
  • Titanium
  • Raw or PVD
  • Low Profile
  • Non-Adjustable

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2A Armament Titanium Gas Block

Recommendation

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

2A Armament Titanium Gas Block

2A Armament Titanium Gas Block

Best Picatinny Gas Block

JP Enterprises Gas Block

Picatinny gas blocks are a great option for replacing standard A2-style front sight posts since most are long enough to cover up the unsightly taper pin holes. They’re also a popular among builders that want to maintain drop-in handguards.

Though it’s possible to keep your drop-in handguards with other gas blocks, you lose some functionality as there’s no way to mount sights and accessories, otherwise.

One downside of picatinny gas blocks, from many peoples perspective, is aesthetics. Some find them to be too big and bulky, taking away from the streamlined profile of the weapon.

Admittedly, it’s very subjective and I’m of the philosophy that you should always use what works for you. And, if that’s a picatinny gas block, that’s great. So, if you’re in the market for one of these gas blocks, the three (3) listed below are great options.

Top Picatinny Blocks Compared (Click ‘Read Review’ to Expand)

JP Enterprises Gas Block JP Enterprises
  • 9.4/10 Rating
  • Carbon Steel
  • Phosphate
  • Picatinny
  • Adjustable

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JP Enterprises Gas Block

Recommendation

Learn More

Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

JP Enterprises Heavy Duty Gas Block

JP Enterprises Gas Block

Midwest Industries Picatinny Gas Block Midwest Industries
  • 9.4/10 Rating
  • Carbon Steel
  • Phosphate
  • Picatinny
  • Non-Adjustable

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Midwest Industries Picatinny Gas Block

Recommendation

Learn More

Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

2A Armament Titanium Gas Block

2A Armament Titanium Gas Block

Yankee Hill Picatinny Gas Block Yankee Hill Machine
  • 9.2/10 Rating
  • Carbon Steel
  • Phosphate
  • Picatinny
  • Non-Adjustable

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Yankee Hill Picatinny Gas Block

Recommendation

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Tech Specs

Material Carbon Steel
Finish Phosphate
Type Low Profile
Adjustable No

Yankee Hill Machine Picatinny Gas Block

Yankee Hill Picatinny Gas Block

Gas Block Major Considerations

After exploring some of the great options above, I think it’s reasonable to assume you now have more questions than answers. That’s where the rest of this guide comes in.

The intent with the next few sections is to explore the key factors you’ll want to consider before purchasing a gas block. Luckily, it’s a pretty simple component and there aren’t that many things to be aware of.

The truth is, you’re good to go as long as the gas block you choose is appropriately sized and accurately machined from durable materials. Though, there are a few minor elements, like finishes, that should be considered as well.

Also, depending on your setup, you will need to decide if an adjustable gas block is required. These gas blocks let you fine tune the amount and pressure of gas seen inside the gas system. This facilitates smooth, reliable, and efficient feeding and extraction of rounds, particularly in short barrel or pistol applications.

Let’s look at all of these in a little more detail and hopefully answer any questions you may have at this point. As always, if I miss anything feel free to let me know.

Gas Block Materials

The gas block is positioned over the gas port and straddles the barrel. Its purpose is to manage the flow of gas through the gas port down the gas tube and into the gas key located on the bolt carrier. It’s a simple, but critical component.

Since it interacts with very hot, high-pressure gas, the gas block has to be made from a sufficiently durable material. Carbon steel, stainless steel, or even titanium are best suited for this application.

Aluminum gas blocks are available, but I generally don’t recommend them. Aluminum is soft and can erode faster than the aforementioned materials. Plus, the expansion rate of aluminum is significantly different than most barrel materials. As such, repeated heat cycling may cause your gas block to come loose over time.

Below, I’ve listed the three most common gas block materials – carbon steel, stainless steel, and titanium. Each has its benefits and risks and the one you choose will come down what suits your application best. Let’s take a look at these materials in detail.

Carbon Steel

Carbon steel is the most popular construction material and it’s perfect for this application. It is very durable, easy to machine, and cost effective. It also offers a small thermal expansion coefficient, meaning it expands very little ass it heats up. This minimizes the potential of your gas block coming loose or moving due to repeated heat cycling.

There are some downsides to carbon steel, however. It is prone to rust and sensitive to some chemicals, which may erode your gas block over time. Because of this, carbon steel requires a corrosion resistant finish like phosphate or melonite.

Stainless Steel

Stainless steel retains many of the positive traits of carbon steel, like durability and small thermal expansion coefficient. Though, it has it’s own characteristics, which make it a great material for this application. Stainless steel is naturally corrosion and chemical resistant, so it doesn’t necessarily need a protective coating. And, it is extremely hard, even compared with carbon steel.

Stainless steel is generally more expensive and harder to machine. As such, you will pay a slight premium for stainless steel gas blocks in most cases. Though, the difference is usually minimal.

Titanium

Titanium is an interesting material and has a lot of benefit that make it a great option for AR-15 gas blocks. Like carbon and stainless steel, titanium is extremely hard and durable. It’s also naturally corrosion and chemical resistant, making a protective finish unnecessary.

On the other hand, titanium is approximately 40% lighter than steel and just as strong. Making it great where low weight and strength are key considerations.

Titanium is typically expensive and difficult to machine, making it even pricier than a stainless steel equivalent. There isn’t much selection, either. Though, prices are coming down and availability is increasing as time goes on.

Gas Block Finishes

The purpose of any finish is to protect the component from premature wear and corrosion. Since the gas block is subjected to very hot, high-pressure gases it is an important consideration.

There are a number of gas block finishes out there and each has its own purported benefits. In most cases, phosphate or nitride finishes are more than adequate.

Some materials like titanium and stainless steel don’t necessarily require a finish. Though, they are sometimes added as an additional layer of protection or even to improve aesthetics.

To keep things simple, I’ll break down a few of the more common finishes available and discuss their pros and cons here.

Phosphate

Phosphate finishes are most popular because they are cheap and easy to apply, but provides good protection against corrosion. Phosphate also offers improved friction properties, though in this case that’s not important.

To apply the finish the gas block is submerged into a heated phosphoric acid solution containing dissolved zinc or manganese phosphate salts. When the metal is placed into the solution, a simple reaction takes place, causing the dissolved salt to fall out of solution and precipitate on the surface.

Overall, this is a tried-and-true finish that is suitably durable for this application. Though, if you are looking for something a bit tougher without a big jump in price, nitride may be a better option.

Nitride

Like phosphate, a nitride finish will protect against corrosion, heat, and will give a longer service life. However, the process provides for a more uniform application and is quite a bit stronger. In fact, the nitride process impinges nitrogen into the steel itself, effectively case hardening it.

Because of these great qualities, a nitride finish is often applied to other AR-15 parts like barrels and bolt carrier groups. Much like the gas block, these components undergo a tremendous amount of stress so the improved durability and lubricity are crucial.

Other Finishes

More exotic finishes like nickel boron or nickel Teflon are becoming more popular, though usually demand a premium price.

Having had quite a bit of experience with these finishes, I can say they are very good. They’re durable and hard-wearing. But they aren’t altogether necessary.

Like I hinted at above, phosphate and nitride work very well and are cheap. But if these finishes match your application or aesthetic, go for it!

Gas Block Sizes

Gas block size is often an afterthought, but obviously important. To guarantee a proper fit, you need to ensure the gas block is the appropriate size for your barrel.

The most common gas block (and barrel) diameter is .750″. Though they are available for thin profile barrels, typically at .625″, as well as thick profile barrels in the .875″ and .936″ range.

These are the standard sizes you will find, but I’m sure others are available, too. Just be sure to consult your manufacturer or use a device like a micrometer or vernier caliper to determine which size you need.

Be aware that additional work may need to be done to fit your new gas block. Often tolerances are so tight that additional honing or sanding may be necessary. This isn’t a bad thing, it just comes with the territory.

Gas Block Attachment Methods

There are two common methods for attaching a gas block to the barrel – either by slipping it on or clamping it on. Slip-on style gas are most popular and considered the more stable, reliable option. Though, clamp-on style gas blocks certainly have their place, too.

Slip-on models simply slide down the barrel and are anchored by setscrews on the underside. Though not totally necessary, it is recommended that you dimple the barrel where the setscrews will tighten down. This guarantees a rock-solid installation and prevents the gas block from coming loose over time.

Like I mentioned above, tolerances can be very tight and often times you need to hone the gas block a little bit so that it slide in place. This is both a pro and con. Since it is such a close fit you probably won’t have any leaks, though the process can be painstaking and time consuming.

Clamp-on style gas blocks forgo this issue. Like slip-on gas blocks they slide down the barrel and are positioned in place, but since their is a small gap in the gas block you can easily accommodate for tolerances. Simply tighten down the screws and you’re good to go.

There are two small down sides, however. The clamping action is inherently not as strong as the set screw option and this style of gas block tends to be a bit bulkier. So, if you have a very thin handguard you can have issues fitting it under there.

I will say, though, both options are perfectly viable and ultimately what you choose will come down to personal taste.

Final Thoughts…

Just to reiterate, there are a lot of great options available and as long as your gas block is accurately machined from quality materials and has a solid finish, you’re good to go. Of course, keep in mind what size you need and and what attachment method you require.

If you’re unsure of what gas block you should choose, or if you don’t know which option above would work best with your budget, you can post your question below in the comment section and I’ll get back to you as soon as possible.

  • Spushin

    You gave absolutely NO justification as to how and why you rated them. FAIL… This is just a fucking commercial…

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