Home Forums Hunting & Shooting AR and Tactical Rifles What is an H-Buffer and why do I want one?

I shot my new rifle with 62 grain TSX bullets over 23.5 and 24 grains of TAC. The gun with a NSX 1-4 in Larue LT104 mount produced a 1.3 inch 5 shot group with the TSX and 24 grains of TAC. I have it zeroed to hit 1 inch high at 100 now with this load. A box of Factory American Eagle 63 grain softpoints shot 5 into 1 inch, and a box of 64 grain WW powerpoints shot 4 into 3.5 inches really very bad. So I will shoot a doe with the TSX this year. What is an H buffer and should I get one? The 24 grains of TAC seems to be a bit hotter than the other ammunition I was shooting.

You can zero a bit higher for a better trajectory past 200. An H buffer is an ounce heavier than a carbine buffer and smooths up the recoil impulse. It can solve some functioning problems too. I run them exclusively.

H and H2 buffers are increasingly heavier in weight as compared to a standard carbine buffer. They allow the bolt to remain locked a bit longer due to the greater weights. the whole objects at rest/objects in motion physics relationship. They can help reduce extraction issues and as RS said do smooth the recoil impulse a bit. First step with extraction issues would be an upgraded ejector spring such as those offered by BCM.

They cover the issue of an incorrect gas port size for the intended use. They have been around for years in various methods. Gas port size is determined by bullet weight/powder charge yet you only generally get to choose by going real custom. So makers come up with weights to cover up the fact that their gas ports are too large for what you are using bullet/load wise.

Jeff

so on a Noveske Light Recce 16 inch should I get an H or H2 for shooting 62 grain TSX bullets with .5 grain of Ramshot TAC under the max load for this powder??

Sorry I can't help, cause I demand that the gas port be done correctly, I never have had to use a bandaid approach for function.

I've got an 16 inch that runs 62 tsx just fine. I'd have to inquire on gas port size as I simply tell my smith what Im' going to shoot, he even solved the port size issue when I went to 90 jlks many years ago.

Jeff

BTW an adjustable gas tube would do the same for you and allow you to change bullets at any time and readjust instead of a different buffer.....

It's really a trial and error exercise to find what works. You typically want the heaviest buffer that allows for proper function. If you went to an H2 and started getting short stroke issues or no bolt lockback, then the H2 is too heavy. Noveske uses an .063 port size in their 14.5" carbine, I'm not sure about their 16" with the carbine length gas system. In a carbine length gas system, the longer the bolt stays locked forward, the lower the pressure and hence easier on parts and extraction. Extraction issues with the carbine length gas system are the reason the military has fielded the heavier 5 coil extractor springs, black spring buffer and extractor o-ring. These are fielded as reliability enhancements on proper .063 diameter gas ports on the 14.5" carbine length gas systems. My LMT 16" carbine runs perfectly fine with an H buffer in it, tho I have never tried the H2. Gas port erosion takes a toll too after firing lots of rounds. If you aren't having any extraction problems, then the main benefit you'll see by switching to a heavier buffer is possibly increased parts life especially on the extractor, bolt, cam key, and smoother recoil. Proper good quality buffer springs are also a necessity as there are lots of poor quality springs available.

Hound va, the buffer face is being marked by the bolt carrier in the new noveske, my RRA gun has had over 1000 rds of XM193 thru it and the buffer tube face is still pristine. What do you make of this? Are the 63 grain TSX/24 grains TAC loads too hot? I have not shot them thru the RRA's gun. The springs "feel" about equally strong..

Colt M4s come from the factory with H buffers. The Standard CAR buffers really are too light.

One port size should work with all NATO or all SAAMI loads regardless of pressure, and if you make it a little bigger it can run both NATO and SAAMI. I don't like them that big, cause I use a suppressor. Bushmaster uses big ports, Colt and LMT port for military ammo.

Moot point if you run a full length receiver extension and a rifle buffer, btw.

Port size makes a HUGE differenc in performance in regards to the pressure curve and powders/ projectiles used. Note I'm not referring to ball issue ammo, I'm talkikng the difference between a fast powder and 40s and slow powder and 90s. Can't work the same.

And its not a moot point due to the extension or buffer, I run a full extension and buffer, and if I ran a standard port with 90jlks I'd have stuck cases and ripped rims constantly...
Jeff

with the marks on my buffer face, I guess I need an H buffer but which one???

not knowing what an H buffer is but reading between the lines, I'd take the heavier one in your situation, but for me its strictly a guess.

The standard rifle buffer that Jeff is talking about weighs 5.2 oz. The standard carbine buffer weighs 2.9 oz. but has a different buffer spring rate. Gas port size is important but with Colt and LMT setting the smallest standard to perform across the board of bullet weights, I wouldn't call an H buffer a bandaid. Just a simpler way of getting the best performance out of a single barrel. Custom barrels are a different horse and rifle extention tubes/buffers need not apply, H buffers are for carbine extention tubes/buffers.

I use H buffers on all of my carbine gas systems, they weigh 3.8 oz. an H2 weighs 4.6 oz., 9MM buffer weighs 5.5 oz. an H3 5.6 oz. (my midlength runs a standard carbine buffer just fine with 77 gr SMK over 24 gr of TAC)

If your Noveske is a mid length gas system (and I think it is) you will probably do fine with a standard carbine buffer but if you run hot loads an H buffer is probably about the heaviest I'd use.

I agree with Jeff that if a particular gun can be setup from the start with a given load and a gas port to match but if you change a rifle stock to a carbine stock, you will need to either get a new barrel or play with buffers and springs to match the bolt speed and save wear and tear on your gun.

Yep Noveske Light RECCE is a midlength and their complete rifle comes with an H buffer.

edit to add they also come with a full auto bolt carrier which weighs an ounce or two more.

Thanks, a local friend of John Noveske's had some Noveske lowers that he sold to another friend at the gunshop that I frequent, its a sad commentary on my life that I know them all.... The gunshop gunsmith installed an VLTOR stock for me and I guess left it with the standard buffer that it comes with. He has H-buffers for $25.00 which I will get and try this week. This is my first experience in reloading for a self loader and I guess the 24 grains of TAC was a bit much for the standard buffer..???

I don't know about the TSX bullets, like I said I run 77 grain Sierra Match Kings and 24 grs of TAC without any problems in my midlength with a standard car buffer. They chronographed 2726 fps (5 shot average) my midlength is a Kreiger 17" RECCE profiled SS match barrel with a wylde chamber and a 1/8 twist.

I started off with an H buffer and can't remember having any problems just tried to shave a little weight from the gun.

Alot of variables could make the load violent in your gun such as a weak buffer spring, tight chamber and bore or a light carrier (Colt half moon). Find out what the max load is for the TSX's and you can sort of tailor the gun to the load by switching out buffers/springs and carriers. Each combo will produce different results.

To test it out, put a round in the chamber and insert an empty mag. You need it to lock the bolt back everytime. I start out trying to find a combo that won't lock it back and trade something out till it does. Remember you still have the pressure in the chamber we're just looking for the softest gas impulse to the mechanics of the gun. Also remember if you shoot lighter loads they may not function in the gun. That's why you have to play around with different things to make sure it functions with everything you're going to shoot or make it a dedicated gun for a specific load.

With your Noveske just get an H buffer and you should be good. I would double check your TSX load as well.

I tried a few things on a 223WSSM gun that worked perfectly with an A2 stock but when the owner changed it out to a collapsable stock, he had way too much going on in the action. I wound up using an extra power action spring and a 9MM buffer to get the gun to run smooth.

Was or is there not a kit out still that has variable weights you can bolt onto your existing carrier to make it as flexible as possible?

I"m pretty much custom all the way, I know what I will use an upper for and prefer to set it up that way, but for the rest, variable weights or gas tubes seem like the best bang for the buck but its out of my territory basicallly.

Jeff

I called Tod at Noveske and he said an H-buffer would run fine, so I bought one, the weight to me is not that much different for the entire gun. I also looked at the carbine buffer that I took out of the gun and it was not only marred by what looked like the bolt carrier but also had significantscratches across its face that could not be related to the recoil impulse. Here is what I think happened. The person that I have known for 16 years just picked up a buffer off his shelf without looking at it and installed it in my VLTOR stock, it happened to be marred and scratched and he did not notice it before he sold it to me. So my gun was probably fine, the loads I was shooting were not harming it.. but I have the H buffer anyway....

Will my POI change with an H-Buffer???

For a midlength the heaviest I'd run would be a H. You may want to check the rear face of the carrier to make sure there are no burs which would mark the face of the buffer. Marking up the finish on the face of the buffer is not necessarily an indication of a problem as a lot of things play a part in the looks of the buffer. I ran a H in my Sabre midlengths for a bit, but it seemed to make cycling a bit sluggish with M193 and M855 ammo. For 25.00 it isn't a huge investment.