It’s easy to forget about the buffer weight in your AR-15 because unless the rifle was built yourself, chances are you’ve never even seen it before. It’s important to not overlook the buffer weight because it’s one of the most important parts in creating your experience as a shooter with that gun. You could have the most expensive trigger and muzzle device in the world but if you’ve got the wrong buffer weight, your AR-15 could operate sub-optimally, not work at all or ruin the experience altogether.
How Does An AR-15 Buffer Weight Work?
When a round is fired from the chamber of an AR-15, gas flows back to push the bolt carrier group towards the shooter as it extracts the spent round’s casing. When that BCG goes back it relies on the buffer weight to send it back into battery which is how the BCG picks up a new round from the magazine and chambers it, getting you ready for the next shot.
All the buffer weight includes is a weight and a spring (sometimes referred to as a “recoil spring”). Depending on the quality of the spring and the amount of weight the buffer has, it can help absorb some of the recoil and provide a smoother cycle of the bolt going back and forth — this creates a better shooting experience and allows for faster follow up shots.
Each buffer will have small individual weights inside that add up to specific weights making it optimal for a certain set of rifles. Depending on the buffer, those individual weights will be a combination of steel and tungsten weights.
Which Buffer Weight To Choose
Every AR-style rifle is going to run a little differently. A lot of factory built guns will tend to run a little over-gassed so that the rifle will run reliably in any weather condition and with a larger variety of ammunition loads. Of course we all prefer a reliable gun over something that doesn’t work but if you’re looking to pick the optimal buffer weight for you to ever so slightly fine tune your AR these are your options to consider:
This buffer will work for carbine-length AR’s, sits at 3.0 ounces and is considered a basic standard that most buffer tube kits and factory built rifles will come with because of its higher reliability. Though buffers may vary in weight, they typically will all look similar to the one in the photo above unless it’s a specialized buffer.
H or H1 Buffer
H (Heavy) and H1 buffers are the same thing but are used interchangeably throughout the internet so no need to get confused about this one. H1 buffers weigh 3.8 ounces. The 20% increase in weight aids in reducing perceived felt recoil and also reduces wear on your AR.
H2 buffers range from 4.5 – 4.7 ounces. If the BCG still feels like it’s cycling too hard, shooters often will choose this buffer to get their carbines to shoot even softer. Any 16” length AR-15 or shorter should be able to use an H2 buffer however every gun does behave differently so the compatibility is going to depend on the coming together of all your other parts as well such as the gas block, BCG, or muzzle device.
Rifle buffers are still around but honestly aren’t seen as often because they’re from an older generation’s design for buffer weights. Most people just use carbine-sized buffers now. Rifle buffers will weigh and vary from 5.0 – 5.2 ounces. Those who do use rifle buffers usually will pair it with a fixed stock such as the mil-spec A2, VLTOR A5, Magpul PRS, MOE Fixed Carbine Stock.
H3 buffers will weigh between 5 to 5.4 ounces, the heaviest among carbine-sized buffers. If the H2 still felt too punchy for you, the same concept from above applies here — the H3 will move even slower due to the heavier weight to alleviate even more recoil. The caveat that all builders should know is that if you go with too heavy of a buffer it can cause the rifle to short stroke. Short stroking can happen with any firearm and symptoms include failure to feed and failure to extract.
Pistol Caliber Buffers
You might instinctively assume that the H3 buffer, most suitable for AR-10 builds, is the heaviest buffer weight out there. False. Pistol caliber buffers are actually the heaviest. Their weights can range from 5 – 8.5 ounces. The reason for this is that pistol caliber AR’s utilize a direct blowback system which applies more pressure to the bolt carrier group than a gas system would. A heavier weight is then needed to soften that impact on the BCG.
If you’re looking for more luxurious and newer designs for a buffer solution consider these:
Geissele Super 42
The Geissele Super 42 features a braided wire buffer spring that boasts it’s complete removal of the annoying “twang” sound that can come from many recoil springs as it’s compressed. Geissele carries these springs with buffer combos in every “H” designated weight (H1, H2, H3).
JP Silent Capture
As we’ve covered in previous blogs, JP Rifles are not for the faint of heart. They’re some of the fastest race guns around that have been consistently winning competitions around the country. Now, JP Enterprises is on their 2nd Generation of the Silent Captured Spring which has a self-contained buffer spring system. It has a reputation for making their rifles be the quietest and one of the smoothest rifles on the market. The Silent Captured Spring is pricey but is available for a wide variety of rifle setups including AR-15 carbine or “standard” buffer, H2, and H3 weights. It will work for AR-10 rifles, AR-9 rifles and they even have a version that is compatible with Law Tactical Folders.
Miculek Magnetic Buffer System
This is a brand new collaboration between world class shooter Jerry Miculek and Big Daddy Unlimited that has come out recently with a patent-pending buffer system that is fully adjustable per your needs. If you want to be an early adopter the Miculek Magnetic Buffer System is definitely worth checking out.
Once you start shopping for buffer weights, you’ll quickly realize there are a ton of options and that you’ll have to pay attention to the exact weight more than the (H) number designation — the weight can sometimes overlap with other “H” buffers. So here’s the breakdown of our suggestions:
Carbine – If you ever experience issues with moving up in buffer weights you can always go back to this one to have your rifle run 100% of the time. It just might have more muzzle flip than you like.
H/H1 – We’re not adding a whole lot of weight moving up from carbine buffers to this one but it is possible for some carbine and mid-length rifles to have cycling issues with the added weight. However, if you’re using a factory built rifle it should be just fine as they come over-gassed enough to be able to handle it.
H2 – We do not recommend H2 buffers for carbine length rifles and while it can work for some mid-length systems it’s not a very commonly used weight.
Rifle – Consider getting one if you are doing some sort of DMR clone with a fixed stock setup otherwise this buffer weight isn’t really the best option for your AR-15.
H3 – If you need an AR-10 buffer weight this is the one. For .308, 7.62×39 and larger calibers, H3 will be your best bet as you’ll need the heavier weight to be able to mitigate some of that recoil.
The good thing about “H” designated buffer weights is that they’re pretty affordable so it wouldn’t hurt to buy a few different ones to see how they behave with your rifle. That being said, specialized buffers are also super cool but will cost significantly more and might not be as viable to experiment with. So make sure you do your research and read or watch as many reviews as possible before making any purchase(s).