How to reduce AR15 recoil WITHOUT adjustable gas block or muzzle brake?

[seanh]

^^^edit... They don't have to be actual certified coaches.. There are plenty of well seasoned shooters that could probably help you along. All. Unfortunately there are a lot of well season shooters that do it wrong, they've simply learned to work around their failure and adapt.


Reducing recoil would be one thing if you were shooting a 7.62, recoil isn't much an issue with with 5.56. I suggest completely removing recoil reduction from your thought process... Just accept it, not use it as an excuse

The fatigue speak of is gonna come from poor form not from excessive recoil.

Tune for reliability and accuracy, Just accept the recoil for what it is.

Don't buy gadgets/stuff to help your time or increase your score...invest in a coach.

 

[Douglas-001]

Smoothy8500 once again shows solid form and technique on a real gun..........good form and solid positions sometimes help make you famous.......too bad I signed a waiver....when it comes to money...NRA never leaves loop holes.....

I admit that the only thing I dislike about Smoothy8500's offhand is the color blue. Reminds me of the michigan wolverines..........and as we all know the only good thing to come out of ann arbor is 23 south bound!!! .......

 

[BattleAxe]

I have a 20" barreled SPR with a JP LMOS and silent captured spring. Also have the same in a shorter carbine set up for NVG use. From my experience it's plug and play with no additional tuning. A shorter carbine length gas system may need tuning.

The SPR has a standard gas block...the night fighter has an adjustable block. Recoil reduction is stellar. BUT on both of those rifles, rapid target acquisition after the shot is important given their use.

That said I shot service rifle in the military and we didn't increase weight to reduce recoil...we did it to keep the rifle more stable, as a body at rest tends to stay at rest. Finding the reticle or sight after a shot is not an issue, as even rapid fire legs are not exactly rapid fire. Plus we were shooting issued team M1As with hot shooting LC match 308 or M118. I wouldn't spend money on a 5.56 operating system except as others have stated... reliability.

 

[TreyMeTrey]

I'm looking to build a Service Rifle AR15 for CMP EIC, and there are certain rules that must be adhered to. The big ones are:

-5.56/.223
-Stoner gas impingement or piston, NO adjustable gas block
-20" barrel max, no portion of the barrel may exceed 0.75" forward of the gas block
-No muzzle brake or compensator. Flash suppressor is allowed, but not required
-To my understanding, there is NO weight limit

There are several other rules and largely don't matter for this post, but for reference, a 4.5 power optic isn't required, but is allowed. The trigger must be a minimum of 4.5 pounds, and can either be a single or two stage. So there is some leeway allowed in the rifle. While I certainly don't want to cheat, if a rule is not explicitly mentioned, I'd assume there is no limitation. But, assuming can be dangerous.

About the only thing I can come up with is a low mass BCG, but I worry about running one without an adjustable gas block. Instead of an adjustable gas block, are there adjustable buffer/springs that can somewhat do the same thing? JP Enterprise silent capture? I know there are adjustable gas tubes, but, I feel that would be pushing it. Is it possible to have a fixed gas block with a smaller gas port, or one that you drill out yourself? That would take a lot of time to tune, but, technically be legal?

My only other thoughts are, I know the flash suppressor isn't a muzzle brake. But does it offer ANY kind of recoil reduction? The rifle is supposed to "exhibit a general overall external appearance to the M-16"; which is how I think the "internal" modifications listed above will probably be acceptable.

Hopefully I'm not just chasing impossible ideas here. If nothing I've mentioned above will work, I'll probably buy a service rifle instead of build. Thanks for any input.

Take Turbo Trout's advice./

 

[TreyMeTrey]

Smoothy8500 once again shows solid form and technique on a real gun..........good form and solid positions sometimes help make you famous.......too bad I signed a waiver....when it comes to money...NRA never leaves loop holes.....


View attachment 7698492


I admit that the only thing I dislike about Smoothy8500's offhand is the color blue. Reminds me of the michigan wolverines..........and as we all know the only good thing to come out of ann arbor is 23 south bound!!! .......

hell yeah!!!!

 

[Usscoloradobb45]

Good grief man.....fuck all that gas block bullshit....get a service rifle that ACTUALLY looks like an issued M16 from way back in the day and stuff lead weights in the stock (A2 stock) and then line the hand guards with lead also. My competition rifle weighs in at almost 17 LBS. No scope. Iron sights. The rifles you see on the firing line today DO NOT look like any type of M16 that was issued long ago. More like match rifles. They are quite fancy with optics that are equally as fancy. Go shoot a plain jane rifle and then add what you feel you may be missing. Last point....I did not know the AR15 generated recoil.........

This/\/\. My long range .223 is over 20 pounds, shoots like a dream. You only need to touch the trigger, there is no recoil.

 

[81STFACP]

OP, contact Whiteoak Armaments/Precision and ask for John H the owner, and tell him that you want a legal service rifle. He can fix you up.

Load up a couple of Ks rounds of shortline ammo and train at reduced course first. Start in slow fire prone, once you get to the point of cleaning the reduced 600 at 100 or 200, you can train on the rest of the stages. By then you should figure out what works for you.

Rifle weight; balanced, forward, or rear becomes evident to you what works for you. Who cares what works for others.

Go to your local matches and try your hand.

By the time you are ready re-barrel you should be on the way to pursue whatever service rifle competition goals you have.

PM Sinister for any questions you have. He is a distinguished rifleman and wears a P100 tab. I think it was 2004, he and I made P100 cut off that year. Those were the A2 days.

 

[smoothy8500]

Nah, OP ain't interested in doing it right. He just wants cool stuff to game it.

Every one of his responses is to find some way around doing it right.... Whether its right equipment, right technique, right experience.

 

[ThunderMass]

I thought his thread was dead; guess not.

^^^edit... They don't have to be actual certified coaches.. There are plenty of well seasoned shooters that could probably help you along. All. Unfortunately there are a lot of well season shooters that do it wrong, they've simply learned to work around their failure and adapt.


Reducing recoil would be one thing if you were shooting a 7.62, recoil isn't much an issue with with 5.56. I suggest completely removing recoil reduction from your thought process... Just accept it, not use it as an excuse

The fatigue speak of is gonna come from poor form not from excessive recoil.

Tune for reliability and accuracy, Just accept the recoil for what it is.

Don't buy gadgets/stuff to help your time or increase your score...invest in a coach.

I gotcha. Yeah, I've got some people to help teach me.

A big reason I wanted to remove as much recoil as possible is so I can't use it as an excuse. Remove as many variables as possible, so it's all on the shooter. Why make hand loads? Well, lots of reasons, but one reason is so you can't blame the factory on messing it up.

I have a 20" barreled SPR with a JP LMOS and silent captured spring. Also have the same in a shorter carbine set up for NVG use. From my experience it's plug and play with no additional tuning. A shorter carbine length gas system may need tuning.

The SPR has a standard gas block...the night fighter has an adjustable block. Recoil reduction is stellar. BUT on both of those rifles, rapid target acquisition after the shot is important given their use.

That said I shot service rifle in the military and we didn't increase weight to reduce recoil...we did it to keep the rifle more stable, as a body at rest tends to stay at rest. Finding the reticle or sight after a shot is not an issue, as even rapid fire legs are not exactly rapid fire. Plus we were shooting issued team M1As with hot shooting LC match 308 or M118. I wouldn't spend money on a 5.56 operating system except as others have stated... reliability.

I'm sorry, but what's an SPR?

Understand on the weight for stability, thanks. I enjoyed shooting the M1, but I would prefer an AR.

Take Turbo Trout's advice./

I will.

This/\/\. My long range .223 is over 20 pounds, shoots like a dream. You only need to touch the trigger, there is no recoil.

I was just looking to see if there were other paths to pursue.

OP, contact Whiteoak Armaments/Precision and ask for John H the owner, and tell him that you want a legal service rifle. He can fix you up.

Load up a couple of Ks rounds of shortline ammo and train at reduced course first. Start in slow fire prone, once you get to the point of cleaning the reduced 600 at 100 or 200, you can train on the rest of the stages. By then you should figure out what works for you.

Rifle weight; balanced, forward, or rear becomes evident to you what works for you. Who cares what works for others.

Go to your local matches and try your hand.

By the time you are ready re-barrel you should be on the way to pursue whatever service rifle competition goals you have.

PM Sinister for any questions you have. He is a distinguished rifleman and wears a P100 tab. I think it was 2004, he and I made P100 cut off that year. Those were the A2 days.

Either White Oak or Rock River, if I buy and don't build. Is there a preference between the two?

I appreciate the advice, thank you.

Nah, OP ain't interested in doing it right. He just wants cool stuff to game it.

Every one of his responses is to find some way around doing it right.... Whether its right equipment, right technique, right experience.

If you read my responses, then you'd also see that I'm not in a position to build or buy at the moment; want me to apologize that my post active duty plans got fucked by covid? Right now I'm just in the planning stage and I just came here to throw out some ideas. I didn't think this would be such a controversial topic.

If you have advice, please share it. If not, don't be an ass, just move on.

 

[smoothy8500]

If you have advice, please share it. If not, don't be an ass, just move on.

Fair enough. If you do buy an upper, White Oak and Rock River are two very popular choices. RRA is a little cheaper. Used is a good choice. I started with that and worked up to WOA stuff.

For scopes, Vortex PST gen1 has a great track record. Vortex has a Ranger line that is almost as good. You want moa target turrets to match scoring rings on target.

coats aren’t needed but help. Even a motorcycle jacket can be used.

sling: get a gi canvas one to start. You can use a welding glove or kitchen mitt to start.

It’s all about having fun and learning.

 

[Mike Shoots Stuff]

With this rifle, using a leather sling and removing the BUIS, pressure pad, and PEQ, I was able to shoot a 479-12X. The rifle weighs about 8.5 lbs.

I know that doesn’t help but I just wanted to point it out that it’s possible to get better scores. The next time I shot service rifle was with the Marine Team, scoring a 488 and then a 495 with their rifles, but mostly I think that was a lot of me improving and working on my mental game.

there’s lead weight. You could potentially try mercury recoil reducers.
Are you looking for recoil reduction in rapid fire, or all around? And for what reason? I’m curious.
I didn’t read all 3 pages of responses because of all the unhelpful, irrelevant posts so my bad if this has already been answered.

 

[lachoneus]

I'd be more proud of myself for building a capable rifle than just shooting one someone else made.

I was more proud of myself when I got to the point of shooting expert scores using a cotton Marine Corps shooting jacket, a sling, an old weightlifting glove and an AR-15 whose only modifications consisted of a free float tube, heavy barrel and 1/2 minute sights. The best advice I got was from a high master who told me to forget spending money on more rifle modifications and instead buy a case of ammo and practice shooting fundamentals.

I'd be more proud of myself for building a capable rifle than just shooting one someone else made.

 

[Mj30wilson900]

Good grief man.....fuck all that gas block bullshit....get a service rifle that ACTUALLY looks like an issued M16 from way back in the day and stuff lead weights in the stock (A2 stock) and then line the hand guards with lead also. My competition rifle weighs in at almost 17 LBS. No scope. Iron sights. The rifles you see on the firing line today DO NOT look like any type of M16 that was issued long ago. More like match rifles. They are quite fancy with optics that are equally as fancy. Go shoot a plain jane rifle and then add what you feel you may be missing. Last point....I did not know the AR15 generated recoil.........

I agree most of the people who try to reduce recoil on the line are using lead weights in the buttstock. Messing with anything else could result in malfunctions during a timed string of fire.

 

[JohnCarter17]

Good grief man.....fuck all that gas block bullshit....get a service rifle that ACTUALLY looks like an issued M16 from way back in the day and stuff lead weights in the stock (A2 stock) and then line the hand guards with lead also. My competition rifle weighs in at almost 17 LBS. No scope. Iron sights. The rifles you see on the firing line today DO NOT look like any type of M16 that was issued long ago. More like match rifles. They are quite fancy with optics that are equally as fancy. Go shoot a plain jane rifle and then add what you feel you may be missing. Last point....I did not know the AR15 generated recoil.........

That was all exposed lead you were using wasn't it?

 

[10X Rifles]

Tune your buffer and spring to your load! Don't drill the gas port unless the rifle will not cycle at all. Buy drilling the gas port, you're putting more gas into the system. Get a heavy buffer and then play with springs. I do not believe the Magpul PRS stock is legal.

 

[ThunderMass]

Fair enough. If you do buy an upper, White Oak and Rock River are two very popular choices. RRA is a little cheaper. Used is a good choice. I started with that and worked up to WOA stuff.

For scopes, Vortex PST gen1 has a great track record. Vortex has a Ranger line that is almost as good. You want moa target turrets to match scoring rings on target.

coats aren’t needed but help. Even a motorcycle jacket can be used.

sling: get a gi canvas one to start. You can use a welding glove or kitchen mitt to start.

It’s all about having fun and learning.
View attachment 7699685

My only reason for going with RRA is that I heard they have a pretty stout military discount. That said, dunno how backed up they are.

I wanted to go with Vortex, but considered the Athlon for the price and the extra half power. Leupold is expensive, but I'd also get a hefty discount. Nightforce, even with the discount, is too much. Still wanna go with Vortex, though.

I can practice with my motorcycle jacket, and gloves until I get a proper setup.

I think I used a nylon sling, and it was difficult to lock in place, and slipped a lot. So canvas does sound better.

Thanks for the input.

With this rifle, using a leather sling and removing the BUIS, pressure pad, and PEQ, I was able to shoot a 479-12X. The rifle weighs about 8.5 lbs.View attachment 7699684
I know that doesn’t help but I just wanted to point it out that it’s possible to get better scores. The next time I shot service rifle was with the Marine Team, scoring a 488 and then a 495 with their rifles, but mostly I think that was a lot of me improving and working on my mental game.

there’s lead weight. You could potentially try mercury recoil reducers.
Are you looking for recoil reduction in rapid fire, or all around? And for what reason? I’m curious.
I didn’t read all 3 pages of responses because of all the unhelpful, irrelevant posts so my bad if this has already been answered.

I just looked at the rules on what the rifle could and could not have, and tried to see what I could do to make the rifle operate better. The recoil is hardly killing me, but I figured reducing recoil couldn't hurt, and it would maybe get me back on target quicker during rapid.

I remember looking into the mercury when I had a 10 gauge coach gun; I regret selling that shotgun.

I was more proud of myself when I got to the point of shooting expert scores using a cotton Marine Corps shooting jacket, a sling, an old weightlifting glove and an AR-15 whose only modifications consisted of a free float tube, heavy barrel and 1/2 minute sights. The best advice I got was from a high master who told me to forget spending money on more rifle modifications and instead buy a case of ammo and practice shooting fundamentals.

That's fair.

I agree most of the people who try to reduce recoil on the line are using lead weights in the buttstock. Messing with anything else could result in malfunctions during a timed string of fire.

Also a fair point. I guess that's why the rifles are over gassed; to increase reliability.

 

[ThunderMass]

Tune your buffer and spring to your load! Don't drill the gas port unless the rifle will not cycle at all. Buy drilling the gas port, you're putting more gas into the system. Get a heavy buffer and then play with springs. I do not believe the Magpul PRS stock is legal.

Right, I was going to start with the spring and buffer. I'd rather not drill the port myself; just seems like something I could easily mess up. But I'm sure someone local could do it.

No, the PRS stock isn't legal. But the UBR is.

 

[sinister]

A big reason I wanted to remove as much recoil as possible is so I can't use it as an excuse. Remove as many variables as possible, so it's all on the shooter. Why make hand loads? Well, lots of reasons, but one reason is so you can't blame the factory on messing it up.

... White Oak or Rock River, if I buy and don't build. Is there a preference between the two?

White Oak, Compass Lake, or Keystone. You'll get a rifle built for you. A Rock River A4 if you want it right now.

Rifles don't have to be OVER-gassed, but they have to function with both magazine-fed and single-feed ammo.

Buy or have a good barrel made to your specs. Choose whether you want a hidden float tube with standard A2 fore-grips, a slick tube, a rail, or a hybrid. Buy your UBR stock (most places have sold out of Gen 1s) and a weight if you need one.

You'll probably want a Geissele National Match or Krieger-Milazzo (Wisconsin) trigger.

The Vortex 1-4X (now called a Ranger) is a solid, affordable choice until you want finer quarter-minute clicks, where it can become your spare/back-up scope. You MUST consider what reticle you want, prefer, need, and can afford (you have your choice of 1/2, 3/4, MOA, and 1.25 MOA dots, with and without an outer circle, and cross-hairs) and whether or not you want adjustable parallax.

Pick a good club and see if they have loaners. My kid shot as a junior with the Utah, Virginia, and Texas teams and they threw more free loaner gear at him than he could possibly ever use. If you still drill you might be eligible for a Navy Reserve loaner once you've shot with them and if you have potential.

 

[smoothy8500]

You'll probably want a Geissele National Match or Krieger-Milazzo (Wisconsin) trigger.

Good point about trigger suggestions. Those two are the most commonly seen if upgrading from a RRA NM 2 stage. Still, a lot of shooters stay with the bargain priced RRA.

 

[BruceInOz]

If you look at the original, genuine AR-10 you will note that across its two major variations, it had both an adjustable gas system AND a ""friction" buffer.

Well, sort-of a buffer; more of a "drag-brake"..

Even the VERY light "Sudanese" pattern AR-10s are not nasty to shoot with full-spec 7.63 NATO Ball ammo., regardless of origin and ambient conditions.

The very early AR-15 carried some of these features over, however, the ".222 Special" was developed along with the rifle and thus more "standardized" than its bigger cousin. Then came the Arctic tests and the later change to Ball Powder and so on.

The "buffer" as seen in later form, has a couple of roles:

Firstly, it actually acts as a "buffer" when the little synthetic rubber truncated cone at the rear strikes the rear of the butt tube, hence the term "buffer".

Secondly, it adds to the total recoiling mass of the bolt / carrier assembly, thus slightly slowing the rearward movement.

Thirdly, because the internal weights are supposed to be "floating" slightly, it acts as a "slide-hammer" to drive the carrier fully forward and, because of those floating weights, reduces "bounce". a vital requirement when going rock 'n roll.

It seems Gene Stoner was never fully satisfied with this, as is clearly shown in his later successful work on "constant recoil" systems in which the bolt / carrier assembly NEVER actually strikes anything to halt rearward movement, but is slowed to a halt by the springs alone, before being thrust forward again.

For further fun, take a look at all the work done to achieve smooth and reliable operation when using the telescoping "shorty" butts.

 

[Mike Shoots Stuff]

Thundermass,

I get what you mean. That recoil won’t beat up a grown man. You could also dry developing a load that’s a bit lighter, I don’t know if Hornady maked a reduced recoil load for 5.56 but they have one for .308 and it’s MOA out of my rifles.
For rapid fire, done well, you should be taking a breath between each shot. My cycle is like this:

-fire, holding back the trigger.
-follow through
-inhale/exhale
-reset the trigger
-fire

it takes about three seconds per cycle.
This season, paying attention to the firing line’s Cadence, the first shot is usually 15 seconds after targets are up. The 1st round in the next magazine for service rifle usually at 30 seconds.
Be fast dropping into position, be deliberate with establishing natural point of aim, and use the cycle. Be fast on the reload. Don’t spend too much time in the spotting scope.
Just my opinion, but building a solid position, having the sling adjusted right, and following the cycle with a good cadence will do more good. Shooters out there will clean rapids with M14s and as issued M1 Garands.

if you start shooting Infantry Team Matches then I’d start looking harder at recoil reduction.

 

[Scout37]

I'm looking to build a Service Rifle AR15 for CMP EIC, and there are certain rules that must be adhered to. The big ones are:

-5.56/.223
-Stoner gas impingement or piston, NO adjustable gas block
-20" barrel max, no portion of the barrel may exceed 0.75" forward of the gas block
-No muzzle brake or compensator. Flash suppressor is allowed, but not required
-To my understanding, there is NO weight limit

There are several other rules and largely don't matter for this post, but for reference, a 4.5 power optic isn't required, but is allowed. The trigger must be a minimum of 4.5 pounds, and can either be a single or two stage. So there is some leeway allowed in the rifle. While I certainly don't want to cheat, if a rule is not explicitly mentioned, I'd assume there is no limitation. But, assuming can be dangerous.

About the only thing I can come up with is a low mass BCG, but I worry about running one without an adjustable gas block. Instead of an adjustable gas block, are there adjustable buffer/springs that can somewhat do the same thing? JP Enterprise silent capture? I know there are adjustable gas tubes, but, I feel that would be pushing it. Is it possible to have a fixed gas block with a smaller gas port, or one that you drill out yourself? That would take a lot of time to tune, but, technically be legal?

My only other thoughts are, I know the flash suppressor isn't a muzzle brake. But does it offer ANY kind of recoil reduction? The rifle is supposed to "exhibit a general overall external appearance to the M-16"; which is how I think the "internal" modifications listed above will probably be acceptable.

Hopefully I'm not just chasing impossible ideas here. If nothing I've mentioned above will work, I'll probably buy a service rifle instead of build. Thanks for any input.

 

[CCFRN]

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I use the BRT system in my LMT MWS 308. I wouldnt hesitate to use it in a 5.56 gun. Its effective and really helped tame an overgassed system, I'd highly recommend their product.

 

[Scout37]

I'm looking to build a Service Rifle AR15 for CMP EIC, and there are certain rules that must be adhered to. The big ones are:

-5.56/.223
-Stoner gas impingement or piston, NO adjustable gas block
-20" barrel max, no portion of the barrel may exceed 0.75" forward of the gas block
-No muzzle brake or compensator. Flash suppressor is allowed, but not required
-To my understanding, there is NO weight limit

There are several other rules and largely don't matter for this post, but for reference, a 4.5 power optic isn't required, but is allowed. The trigger must be a minimum of 4.5 pounds, and can either be a single or two stage. So there is some leeway allowed in the rifle. While I certainly don't want to cheat, if a rule is not explicitly mentioned, I'd assume there is no limitation. But, assuming can be dangerous.

About the only thing I can come up with is a low mass BCG, but I worry about running one without an adjustable gas block. Instead of an adjustable gas block, are there adjustable buffer/springs that can somewhat do the same thing? JP Enterprise silent capture? I know there are adjustable gas tubes, but, I feel that would be pushing it. Is it possible to have a fixed gas block with a smaller gas port, or one that you drill out yourself? That would take a lot of time to tune, but, technically be legal?

My only other thoughts are, I know the flash suppressor isn't a muzzle brake. But does it offer ANY kind of recoil reduction? The rifle is supposed to "exhibit a general overall external appearance to the M-16"; which is how I think the "internal" modifications listed above will probably be acceptable.

Hopefully I'm not just chasing impossible ideas here. If nothing I've mentioned above will work, I'll probably buy a service rifle instead of build. Thanks for any input.

 

[phlegethon]

Oh good, a 20 minute YouTube video with no explanation. What an excellent use of my time.

 

[TonyTheTiger]

Oh good, a 20 minute YouTube video with no explanation. What an excellent use of my time.

And you have to watch it twice since it was posted twice.

 

[TreyMeTrey]

Fair enough. If you do buy an upper, White Oak and Rock River are two very popular choices. RRA is a little cheaper. Used is a good choice. I started with that and worked up to WOA stuff.

For scopes, Vortex PST gen1 has a great track record. Vortex has a Ranger line that is almost as good. You want moa target turrets to match scoring rings on target.

coats aren’t needed but help. Even a motorcycle jacket can be used.

sling: get a gi canvas one to start. You can use a welding glove or kitchen mitt to start.

It’s all about having fun and learning.
View attachment 7699685

Are they still limited to a 4.5 Power scope and a 4 lb trigger to shoot High Power with the AR15 ?

 

[Farsight]

If you shoot whatever you build so much it becomes part of you, I believe the recoil will become part of your rhythm.

 

[smoothy8500]

Are they still limited to a 4.5 Power scope and a 4 lb trigger to shoot High Power with the AR15 ?

Yes, 4.5 x power, 4.5 lbs minimum trigger pull.

 

[rpoL98]

one thing I've done to restrict gas flow on a gas block, on the gas block, from the bottom, tap the hole that goes from the barrel journal to the gas tube hole. the size of the tap will depend on the existing drilled hole size in your gas block. I had to use a long-reach tap (which I had to order). you just get the tap started, maybe cut 1 or 2 threads.

based on the threads you cut, get the shortest possible SS flat-point set screw (e.g. McMaster-Carr). you file down the hex socket end of the set screw until there's only just enough depth in the hex socket to engage the hex key reliably (straight end, not ball-end). then you drill the desired size hole in the set screw, from the bottom of the hex recess. I found that the hex recess on small set screws isn't always perfectly centered. This is your gas flow restrictor. Sorta like the old-school Holley carburetor jet.

you want to make sure that you cut enough threads in the gas block so that the restrictor set screw sits flush in the gas block barrel journal, but you don't want to thread the hole too much so that the set screw protrudes into the gas tube hole. You want the set screw to bottom out in the threads. It's a careful fitting process.

I did this for an A2 FSB 7.62x39 (M4 carbine style) that was way over-gassed where a 8.5oz buffer didn't slow it down enough, and also for an Adams Arms P-series low-profile piston gas block. I wanted to restrict the gas flow at the source (e.g. gas block), and not back at the bolt carrier.

for the A2 FSB, I coulda farted around with the BRT restrictor gas tubes, but with the set-screw FSB, I could drill the set screw larger if the gas was restricted too much, or make a new set screw with a smaller orifice if I had gone too large. didn't have to order up a new gas tube, and I was using a black nitride gas tube (for looks) anyways. It took me 5 iterations to get the set-screw drilled-hole size "just right".

for the Adams Arms gas block (also M4 carbine config), well, it's piston, and this is what it took to make it work. This one took me 4 iterations to get it "just right".

BRT used to sell a kit like this, not sure if they still do. But they didn't have it with the A2 FSB, and certainly not with an Adams Arms piston GB.


when you get to the end of your rope, you resort to desperate means.

 

[BruceInOz]

Where the gas pressure AND dwell time actually count is INSIDE the bolt / carrier assembly.

Consider the long struggle with "shorty" gas systems..

You can either restrict the flow at the port in the barrel or further back, in its passage along the tube and into the carrier. Over-gassing the carrier will rapidly lead to fouling and erosion of components, as well as possible damage to the "buffer" tube and related components.. In recent years, some folks have been tinkering with LONG tubes on SHORT barrels: Pigtails, swithchbacks, etc. This actually makes some sense.

The AR system is sort-of self regulating in that as soon as there is sufficient pressure present, the carrier will start to move rearwards, cutting off any further gas flow as it does AND venting the gas present inside the carrier as it continues to move,, via those little holes on the right side of the carrier. All well and good, but if the INITIAL gas impulse has been "excessive", the rearwards acceleration of the carrier will be "brisk", indeed. This leads to stress on the buffer tube, for starters, and especially in "carbine-length" butt tubes. Furthermore, if the action opens TOO fast, while there is till serious residual bore pressure, things may get distinctly unpleasant..

The "service" rifles were built AROUND the ammo. Count the Necessary mechanical changes (the MEAT, not the "fruit"), in the development of the M-16A1 into the A2. EVERY time a shooter changes the ammo recipe, things happen differently, and not just on the target.

The 5.56 NATO / .223 Rem cartridge is NOT a .22-250 Ackley Improved in disguise, nor was it ever intended to be. Nor will the laws of Physics be bent without the occasional "interesting" consequence. Balance and "harmony" will ultimately outperform and outlast brute force.

AR "Zen"

 

[JohnCarter17]

My first thought to smoothen it out would be a VLTOR A5 with H2 buffer (5.3 oz) and Tubbs flatwire spring.
Shoot that and see if you want to continue tweaking.

If you want to fiddle with the gas, then try a RCA adjustable gas key on your BCG.

 

[Farsight]

Reliability issues are more possible with more modifications, so I would no longer call it a Service Rifle. The name of this class just seems to imply you are using an un-modified weapon, so maybe better called service your rifle class.

 

[sinister]

I use an A5 extension and XH buffer with GI spring on both my primary and back-up rifles.

They're not magic. I still have to dope the wind, point the rifle, and break the shot.

 

[Phatcow]

Have you considered increasing your mass? I personally recommend mixing smooth peanut butter with icecream