A somewhat in depth look at how to tune an AR

[DonovanM]

I have been looking into this as I've encountered a few idiosyncrasies with my personal rifles that I've been working on debugging. Unlike with pistols, I do believe that "tuning" is actually a big part of getting a rifle to shoot flat without exerting too much muscular tension on it or putting something ridiculous like an SJC Titan on the end, which is basically half a pound of overkill.

The biggest consideration with tuning an AR is obviously going to be the amount of gas being used and how that correlates with the mass of the reciprocating components. I have found that you can achieve pretty good - not great - shootability with full mass operating system components, but lower mass is highly preferred.

Common doctrine seems to be to tune your gas block to give only as much gas as is necessary to lock the bolt back, plus some arbitrary amount to account for ammunition variations, whether that's velocity within the same lot or between brands. This method is a good baseline - a fine minimum, but I have found that leaving it this way more often than not leads to an undergassed state in some of my rifles where the recoil has an obviously slow and "chunky" feel to it (cyclic rate too low), especially noticeable with full mass components. The effect of overgassing with lighter components has manifested as a "smack" at the end of the recoil cycle where the muzzle noticeably dips sharply under recoil.

My theory is that any given value of total reciprocating mass in the operating system will have a corresponding value - or range - of cyclic rates that will decrease noticeability to the shooter and improve the rifle's shootability. Or, that perhaps there is a "one size fits all" optimum cyclic rate that works with all values of reciprocating mass. Either way, the goal of tuning the gas block is simply to get inside this range of values. Luckily, once there, reliability should be maintained as an under or over gassed state should be noticeable to the shooter and is what usually accounts for the majority of feeding or extraction-related issues in ARs.

To receive the best feedback from the rifle about the amount of gas to use, I believe it is beneficial to tune the gas block without a muzzle device attached - or one that doesn't have an impact on felt recoil or muzzle deviation - a pure flash hider, but it has to be symmetrical, ie not something like an A2.

As soon as we get as close as we can to the optimum amount of gas - it will most likely not end up being "perfect" - especially with gas blocks with a more coarse adjustment like the Syrac - the preferred (for now) muzzle device can then be attached to assess it's effect on the final product. I believe that compensators should serve as a supplement to an already tuned rifle, much like protein powder to an already healthy diet.

The ideal compensator would allow the user to tune the escaping gas vectors to counteract the muzzle drift left over once the tuning is right. Since no user is able to offer complete 360 degree support of the rifle when it fires, recoil will always have a path of least resistance it can follow to allow the rifle to drift off target. Many compensators attempt to correct for this with varying degrees of effectiveness, but there is no one size fits all solution, as the gas pressure at the muzzle, which determines the effectiveness of a compensator's asymmetrical directional ports, is going to be different between varying barrel lengths and gas systems, to say nothing of the ammunition being used.

Unfortunately, truly tuneable compensators are few and far in between. There is the Rolling Thunder comp, which while effective, is again half a pound of overkill. The Ares Armor comp is an interesting and completely tuneable design but will lack the effectiveness of brakes with a nice, large baffle area for the escaping gas to strike, thus reducing recoil. The Surefire SOCOM-series muzzle brake has a similar design to the Rolling Thunder with the "tuneable" ports in the high-pressure chamber, while remaining relatively small and lightweight, but the high surface hardness of the Ionbond DLC coating will somewhat inhibit a user's ability to tune the compensator at the range with a cordless drill.

Once done we should have a rifle optimally set up, not for the short or long games where anything serviceable and accurate will work, but in the intermediate game, perhaps around the 50 yard mark where an 8" plate rack or paper targets are best shot offhand.

What I really wish is to have access to high speed cameras to actually measure the optimum cyclic rates of full and low-mass operating systems and see if they are different - or if there is a "one size fits all" range of cyclic rates that will work with everything. Sigh, one day.

I have never gotten to shoot a JP rifle, but by all accounts they are the best shooting ARs out there. I imagine they figured all this stuff out at the factory when I was still in middle school, which consequently explains why they have their own bespoke spring rates, buffer/bolt carrier weights, adjustable gas systems and compensators that when combined produce the feel that everyone is looking for - hence the production backlog, and their preferred use by the best shooters in the world who have the luxury of running whatever they want.

Your comments, agreements and disagreements are very much appreciated

Edited December 3, 2013 by DonovanM

[MarkCO]

You have some really good observations.

The reason we went to Nordic with a barrel design is because so many barrels have a gas port diameter that results in to much gas to the system. So, instead of fixing the gas port size, adjustable gas was used, but that introduces another failure point in the system.

There are actually multiple recoil impulses when firing an AR, three of them are inter-related; unlocking, mass of the BCG stopping at the rear of the tube, and then mass stopping at lock-up again. Buffer mass, spring rate, BCG mass all have an impact here. There are a lot of trinkets out there that will claim to do certain things, but most are for only one set of conditions. A total mass of about 9 to 10 ounces feels pretty good to a wide array of shooters. I know of few who run empty carbine buffers to cut the weight a bit more. When you get under about 8 ounces, you are on the ragged edge and have a system that will either wear faster, or which must be constantly tuned for the ammo and environmental conditions.

I have been critical of some of the "famous" comps for sure, but there is a lot going on with a comp that is part of a system. That is one reason we recommend the 2.1 ounce Dynamic Resistance comp, the Seekins comp, and why I finally broke down and made the prototype of the Gas Hog. The focus of these comps, with slightly different engineering approaches, was to gain "neutrality" in order to reduce the amount of tuning needed by the end user. Light, simple, no high pressure port, reduced concussion and effective. No need for bricks on the muzzle anymore.

[fastshooter03]

Yup, even the type of rifling can affect what size gas port will be effective at cycling the action in a 18" rifle length barrel.

So if you can't make your own barrels and comps like I can, dealing with a company that has their stuff figured out and tuned for what you want is a big plus.

Nick

[APL-G35]

Good info Mark. I've built plenty of my own comps but have recently settled on a seekins comp myself. I am currently running a standard weight bcg and buffer setup but have been researching lightweight setups. After seeing some of the test targets jesse tischauser and Keith Garcia have posted of their tests with a titanium carrier setup. I thought it would be a worthwhile venture. It was eye opening to see what the reduced weight effect had on doubles at 50 yds for them. Is there a point of diminishing return or the probability of catastrophic failure when it's too light? I have head that a 1911 slide under 11oz will chew up the locking lugs. Is there anything like that happening with these setups?

[Vespid_Wasp]

Light, simple, no high pressure port, reduced concussion and effective. No need for bricks on the muzzle anymore.

Would you mind going into a little more detail about why you wanted to get away from having high pressure ports? If I understand correctly, the flats on a comp give gas a place to strike, exert a force, and counteract recoil. If the combination of internal forces, like recoil along the axis of the BCG, and external forces like our hand on the handguard, introduce movement in the rifle.... wouldn't a jet of gas opposing that movement be desirable? I am not an engineer but I do enjoy learning anything I can about the mechanics of flat shooting rifles.

[DonovanM]

One downside of high pressure chambers is that you can't clean the barrel crown without removing the muzzle device, which is no bueno if it's pin and welded.

[stephen1776]

I recently bought a Nordic 18" 223 wylde and put a DreadNaught F2 Comp on it, coupled with a ACE Skelton Stock and Low Pro non adjustable gas block. I dont think I could ask for aything much better without chopping down the money tree, to afford a JP rifle, with all the low mass bells and whistles.

[MarkCO]

If the initial "chamber" has a high pressure port, that greatly increases the carbon build-up on the crown. When the "curls" of carbon are liberated, you can get baffle strikes, or worse. The build-up also degrades accuracy. While I would rather not say who, or which comp, a very recognizable top shooter was having a heck of a time hitting a longer distance target at a major, raised some eyebrows, including mine. When he put his rifle on the rack I went and looked at it. There were three baffle strikes on the comp and a curl of hardened carbon hanging out of the port. Also, high pressure ports significantly increase concussion. For some shooters, they don't mind, but for others it can be a great detractor. Fundamentally, if you understand gas dynamics, high pressure ports are not needed. They are used because they provide a simple method to "tune" the comp to the system which makes it more "effective" for a specific set of conditions and shooter.

When a comp is designed to be "neutral" as the three I mentioned are, then the need for tuning is reduced, the comp works "effectively" across a greater range of operating parameters and will therefore work well for a wider range of shooters and set-ups. The Jet engine creates thrust by "throwing" the combustion products out of the engine. If you were to sit in a small boat, and throw out a bowling ball, the equal and opposite force would move you in the opposite direction of the thrown ball. In the AR, we are attempting to counter this type of force 4 times, and the primary and secondary pressure drop forces at the muzzle.

As for the design process of these three comps...I would say they were designed differently than any of the other comps on the market that generally use the theory of striking flat surfaces with gas and then attempting to control the resultant vectors with high pressure port tuning. As a result, they can do more with less. If you have a comp that works well for you, by all means keep it. If you have a comp that does not allow 50 yard doubles in the A zone, you probably need to tune your comp, which for some people is a daunting task. These comps will work for a wider range of shooters and systems because of the neutral design approach. The specifics...seeing as how I have already seen an attempt to copy the geometry of one of these comps, I'd rather not explain the design details at this point.

As for the mass of the BCG and buffer, some balance is beneficial. Also, realize that there are some systems being designed and or marketed that are NOT suitable for a general use AR, nor even an across the course 3Gun AR. If I am running a 45 grain bullet at 2300 fps out of an AR, what do you think happens when I put a 77 grain slug at 2700 fps out the muzzle? Folks need to remember that the AR platform has operational windows based on the parts chosen. Get too close to either edge and you may not like the results. I see people "happy" with this or that new gadget, but sorry, 500, or even 2000 rounds is not even close to proving sufficiency.

The fundamental reason why JPRifles has enjoyed such success is that fundamentally, they understand that window in which their rifles are likely to be used. Some people like to shift that window one way or the other a little bit. Fundamentally, most production ARs are based on the M4 operation window which uses the heavier BCG to decrease cyclic rate. So they need more gas from a port closer to the chamber that also has higher pressures. So, then they add chrome lining in an attempt to retard gas port erosion and increase lifespan of the barrel. Some call this "Mil-Spec" and market the heck out of it, but it is not the best window for the vast majority of ARs to be built within. The average M4gery buyer does not have even close to the requisite skill to be able to enjoy a shifted operational window. Any time you change ammo, or the comp, barrel, gas system, buffer, buffer spring, or BCG parameters, you need to understand how that change will affect the other parameters and where you have moved within the operational window.

[Vespid_Wasp]

Thank you for the detailed response! I do like my current compensator but I have found that the crown of the barrel does need to be cleaned more frequently than I would like.

It's nice to have so many quality options.

[co-exprs]

If the initial "chamber" has a high pressure port, that greatly increases the carbon build-up on the crown. When the "curls" of carbon are liberated, you can get baffle strikes, or worse. The build-up also degrades accuracy. While I would rather not say who, or which comp, a very recognizable top shooter was having a heck of a time hitting a longer distance target at a major, raised some eyebrows, including mine. When he put his rifle on the rack I went and looked at it. There were three baffle strikes on the comp and a curl of hardened carbon hanging out of the port. Also, high pressure ports significantly increase concussion. For some shooters, they don't mind, but for others it can be a great detractor. Fundamentally, if you understand gas dynamics, high pressure ports are not needed. They are used because they provide a simple method to "tune" the comp to the system which makes it more "effective" for a specific set of conditions and shooter.

When a comp is designed to be "neutral" as the three I mentioned are, then the need for tuning is reduced, the comp works "effectively" across a greater range of operating parameters and will therefore work well for a wider range of shooters and set-ups. The Jet engine creates thrust by "throwing" the combustion products out of the engine. If you were to sit in a small boat, and throw out a bowling ball, the equal and opposite force would move you in the opposite direction of the thrown ball. In the AR, we are attempting to counter this type of force 4 times, and the primary and secondary pressure drop forces at the muzzle.

As for the design process of these three comps...I would say they were designed differently than any of the other comps on the market that generally use the theory of striking flat surfaces with gas and then attempting to control the resultant vectors with high pressure port tuning. As a result, they can do more with less. If you have a comp that works well for you, by all means keep it. If you have a comp that does not allow 50 yard doubles in the A zone, you probably need to tune your comp, which for some people is a daunting task. These comps will work for a wider range of shooters and systems because of the neutral design approach. The specifics...seeing as how I have already seen an attempt to copy the geometry of one of these comps, I'd rather not explain the design details at this point.

As for the mass of the BCG and buffer, some balance is beneficial. Also, realize that there are some systems being designed and or marketed that are NOT suitable for a general use AR, nor even an across the course 3Gun AR. If I am running a 45 grain bullet at 2300 fps out of an AR, what do you think happens when I put a 77 grain slug at 2700 fps out the muzzle? Folks need to remember that the AR platform has operational windows based on the parts chosen. Get too close to either edge and you may not like the results. I see people "happy" with this or that new gadget, but sorry, 500, or even 2000 rounds is not even close to proving sufficiency.

The fundamental reason why JPRifles has enjoyed such success is that fundamentally, they understand that window in which their rifles are likely to be used. Some people like to shift that window one way or the other a little bit. Fundamentally, most production ARs are based on the M4 operation window which uses the heavier BCG to decrease cyclic rate. So they need more gas from a port closer to the chamber that also has higher pressures. So, then they add chrome lining in an attempt to retard gas port erosion and increase lifespan of the barrel. Some call this "Mil-Spec" and market the heck out of it, but it is not the best window for the vast majority of ARs to be built within. The average M4gery buyer does not have even close to the requisite skill to be able to enjoy a shifted operational window. Any time you change ammo, or the comp, barrel, gas system, buffer, buffer spring, or BCG parameters, you need to understand how that change will affect the other parameters and where you have moved within the operational window.

2012 RM3G. I was shooting in the RO squad with Barry Dueck. After 7 stages I was up on him by maybe 1%. We were going into the two long range rifle stages. Being a local I was extremely well practiced at the distances, terrain and at atmo for these stages and was confident I could maintain or increase my lead. I tanked both those stages and dropped 2 places on the leader board. I was dumb founded by how hard it was to hit anything beyond 250yds. I mean it seemed as though my rounds were flying to completely random points of impact on targets I shoot all year long. I figured it was just big match jitters or something lame like that. A week after I got home I was looking over my rifle and noticed some shinny marks on the edges of the baffles in my famous, name brand brake. The one I bought because everyone on Enos says that it's the best of the best of the best. I pulled the brake to find the pressure chamber completely packed with carbon. I threaded on a different brake I had and hit the range to find that I was once again hitting targets without any drama. I was so mad I threw the packed up brake in the trash and went on the hunt for a 308 brake without a pressure chamber. I've been through several different brakes now and have found a couple of good ones which are just as effective as the one I had, but are shorter, lighter and lower maintenance. I am currently running the Dynamic Resistance 308 brake and have found it to work as well as any other 308 brake on the market with the previously listed benefits. Oh... and it's not a concussion grenade.

[Jesse Tischauser]

If the initial "chamber" has a high pressure port, that greatly increases the carbon build-up on the crown. When the "curls" of carbon are liberated, you can get baffle strikes, or worse. The build-up also degrades accuracy. While I would rather not say who, or which comp, a very recognizable top shooter was having a heck of a time hitting a longer distance target at a major, raised some eyebrows, including mine. When he put his rifle on the rack I went and looked at it. There were three baffle strikes on the comp and a curl of hardened carbon hanging out of the port. Also, high pressure ports significantly increase concussion. For some shooters, they don't mind, but for others it can be a great detractor. Fundamentally, if you understand gas dynamics, high pressure ports are not needed. They are used because they provide a simple method to "tune" the comp to the system which makes it more "effective" for a specific set of conditions and shooter.

When a comp is designed to be "neutral" as the three I mentioned are, then the need for tuning is reduced, the comp works "effectively" across a greater range of operating parameters and will therefore work well for a wider range of shooters and set-ups. The Jet engine creates thrust by "throwing" the combustion products out of the engine. If you were to sit in a small boat, and throw out a bowling ball, the equal and opposite force would move you in the opposite direction of the thrown ball. In the AR, we are attempting to counter this type of force 4 times, and the primary and secondary pressure drop forces at the muzzle.

As for the design process of these three comps...I would say they were designed differently than any of the other comps on the market that generally use the theory of striking flat surfaces with gas and then attempting to control the resultant vectors with high pressure port tuning. As a result, they can do more with less. If you have a comp that works well for you, by all means keep it. If you have a comp that does not allow 50 yard doubles in the A zone, you probably need to tune your comp, which for some people is a daunting task. These comps will work for a wider range of shooters and systems because of the neutral design approach. The specifics...seeing as how I have already seen an attempt to copy the geometry of one of these comps, I'd rather not explain the design details at this point.

As for the mass of the BCG and buffer, some balance is beneficial. Also, realize that there are some systems being designed and or marketed that are NOT suitable for a general use AR, nor even an across the course 3Gun AR. If I am running a 45 grain bullet at 2300 fps out of an AR, what do you think happens when I put a 77 grain slug at 2700 fps out the muzzle? Folks need to remember that the AR platform has operational windows based on the parts chosen. Get too close to either edge and you may not like the results. I see people "happy" with this or that new gadget, but sorry, 500, or even 2000 rounds is not even close to proving sufficiency.

The fundamental reason why JPRifles has enjoyed such success is that fundamentally, they understand that window in which their rifles are likely to be used. Some people like to shift that window one way or the other a little bit. Fundamentally, most production ARs are based on the M4 operation window which uses the heavier BCG to decrease cyclic rate. So they need more gas from a port closer to the chamber that also has higher pressures. So, then they add chrome lining in an attempt to retard gas port erosion and increase lifespan of the barrel. Some call this "Mil-Spec" and market the heck out of it, but it is not the best window for the vast majority of ARs to be built within. The average M4gery buyer does not have even close to the requisite skill to be able to enjoy a shifted operational window. Any time you change ammo, or the comp, barrel, gas system, buffer, buffer spring, or BCG parameters, you need to understand how that change will affect the other parameters and where you have moved within the operational window.

2012 RM3G. I was shooting in the RO squad with Barry Dueck. After 7 stages I was up on him by maybe 1%. We were going into the two long range rifle stages. Being a local I was extremely well practiced at the distances, terrain and at atmo for these stages and was confident I could maintain or increase my lead. I tanked both those stages and dropped 2 places on the leader board. I was dumb founded by how hard it was to hit anything beyond 250yds. I mean it seemed as though my rounds were flying to completely random points of impact on targets I shoot all year long. I figured it was just big match jitters or something lame like that. A week after I got home I was looking over my rifle and noticed some shinny marks on the edges of the baffles in my famous, name brand brake. The one I bought because everyone on Enos says that it's the best of the best of the best. I pulled the brake to find the pressure chamber completely packed with carbon. I threaded on a different brake I had and hit the range to find that I was once again hitting targets without any drama. I was so mad I threw the packed up brake in the trash and went on the hunt for a 308 brake without a pressure chamber. I've been through several different brakes now and have found a couple of good ones which are just as effective as the one I had, but are shorter, lighter and lower maintenance. I am currently running the Dynamic Resistance 308 brake and have found it to work as well as any other 308 brake on the market with the previously listed benefits. Oh... and it's not a concussion grenade.

Which break was causing the build up?

[Jesse Tischauser]

Great post Donovan!

[co-exprs]

If the initial "chamber" has a high pressure port, that greatly increases the carbon build-up on the crown. When the "curls" of carbon are liberated, you can get baffle strikes, or worse. The build-up also degrades accuracy. While I would rather not say who, or which comp, a very recognizable top shooter was having a heck of a time hitting a longer distance target at a major, raised some eyebrows, including mine. When he put his rifle on the rack I went and looked at it. There were three baffle strikes on the comp and a curl of hardened carbon hanging out of the port. Also, high pressure ports significantly increase concussion. For some shooters, they don't mind, but for others it can be a great detractor. Fundamentally, if you understand gas dynamics, high pressure ports are not needed. They are used because they provide a simple method to "tune" the comp to the system which makes it more "effective" for a specific set of conditions and shooter.

When a comp is designed to be "neutral" as the three I mentioned are, then the need for tuning is reduced, the comp works "effectively" across a greater range of operating parameters and will therefore work well for a wider range of shooters and set-ups. The Jet engine creates thrust by "throwing" the combustion products out of the engine. If you were to sit in a small boat, and throw out a bowling ball, the equal and opposite force would move you in the opposite direction of the thrown ball. In the AR, we are attempting to counter this type of force 4 times, and the primary and secondary pressure drop forces at the muzzle.

As for the design process of these three comps...I would say they were designed differently than any of the other comps on the market that generally use the theory of striking flat surfaces with gas and then attempting to control the resultant vectors with high pressure port tuning. As a result, they can do more with less. If you have a comp that works well for you, by all means keep it. If you have a comp that does not allow 50 yard doubles in the A zone, you probably need to tune your comp, which for some people is a daunting task. These comps will work for a wider range of shooters and systems because of the neutral design approach. The specifics...seeing as how I have already seen an attempt to copy the geometry of one of these comps, I'd rather not explain the design details at this point.

As for the mass of the BCG and buffer, some balance is beneficial. Also, realize that there are some systems being designed and or marketed that are NOT suitable for a general use AR, nor even an across the course 3Gun AR. If I am running a 45 grain bullet at 2300 fps out of an AR, what do you think happens when I put a 77 grain slug at 2700 fps out the muzzle? Folks need to remember that the AR platform has operational windows based on the parts chosen. Get too close to either edge and you may not like the results. I see people "happy" with this or that new gadget, but sorry, 500, or even 2000 rounds is not even close to proving sufficiency.

The fundamental reason why JPRifles has enjoyed such success is that fundamentally, they understand that window in which their rifles are likely to be used. Some people like to shift that window one way or the other a little bit. Fundamentally, most production ARs are based on the M4 operation window which uses the heavier BCG to decrease cyclic rate. So they need more gas from a port closer to the chamber that also has higher pressures. So, then they add chrome lining in an attempt to retard gas port erosion and increase lifespan of the barrel. Some call this "Mil-Spec" and market the heck out of it, but it is not the best window for the vast majority of ARs to be built within. The average M4gery buyer does not have even close to the requisite skill to be able to enjoy a shifted operational window. Any time you change ammo, or the comp, barrel, gas system, buffer, buffer spring, or BCG parameters, you need to understand how that change will affect the other parameters and where you have moved within the operational window.

2012 RM3G. I was shooting in the RO squad with Barry Dueck. After 7 stages I was up on him by maybe 1%. We were going into the two long range rifle stages. Being a local I was extremely well practiced at the distances, terrain and at atmo for these stages and was confident I could maintain or increase my lead. I tanked both those stages and dropped 2 places on the leader board. I was dumb founded by how hard it was to hit anything beyond 250yds. I mean it seemed as though my rounds were flying to completely random points of impact on targets I shoot all year long. I figured it was just big match jitters or something lame like that. A week after I got home I was looking over my rifle and noticed some shinny marks on the edges of the baffles in my famous, name brand brake. The one I bought because everyone on Enos says that it's the best of the best of the best. I pulled the brake to find the pressure chamber completely packed with carbon. I threaded on a different brake I had and hit the range to find that I was once again hitting targets without any drama. I was so mad I threw the packed up brake in the trash and went on the hunt for a 308 brake without a pressure chamber. I've been through several different brakes now and have found a couple of good ones which are just as effective as the one I had, but are shorter, lighter and lower maintenance. I am currently running the Dynamic Resistance 308 brake and have found it to work as well as any other 308 brake on the market with the previously listed benefits. Oh... and it's not a concussion grenade.

Which break was causing the build up?

Rolling Thunder and only 1000rds of 308, it was toast. That experience broke the cycle of buying whatever everyone else says is awesome and figure out what works on my own, and is why you often see me post about liking unconventional products and equipment set ups.

[kurtm]

Ill just throw this out there. Powder choice plays a HUGE part in how much carbon build up you get in your high pressure ports. Also tuning your AR to your style of shooting can mask poor technique....kind of like when you get someone else's pistol and the rear sight is cranked way up and all the way to the right to make up for bad trigger control.

[Meat Target]

I veiw the comp like other parts of the AR, it needs to be cleaned. Just about any rifle comp will build up carbon if you shoot enough. Just hose it down with some oven cleaner let it sit a bit and scrub with a small brush (old bore brushes work geat) then rinse. May need to use the edge of a brass rod to scape the hard to reach spots but it not a big deal, you really only need to do it once or twice a year.

[pcs352]

DonovanM & MarkCO....what an awesome read. Thank you gentlemen!

[CMV]

Lots of great info here. Thank you all.

[Dustbuster1]

Good post, as stupid as it sounds I enjoy tweaking the gas system, and compensators. Reading about good theory of operation is a big plus. Above all trying to keep the rifle simple and efficient is my goal. Thanks again!

[Butterpuc]

My AR is not tuned and I shoot factory ammunition, which is the primary reason for not attempting to tune this particular AR. But now that I have other ARs, I have been contemplating setting this one up for a dedicated 3gun (400-600 yard accurate rifle) and keep the rest of my ARs setup for short 3gun courses (red dot optic) and general use AR. I have been toying with the idea of changing my Miculek Brake on my AR to a Seekins Precision or JP Bennie Cooley (I would like it to match my stainless barrel).

After reading this, I feel like I shouldn't, I feel like should start tuning from the back forward.

[MarkCO]

After reading this, I feel like I shouldn't, I feel like should start tuning from the back forward.

The Miculek is a very good brake, but I think your observation makes sense. Pick the parts you want and move forward.

[Artsville]

this is perfect timing....I run a stag 3G with a Miculek brake. I reload but a mild load for my area matches. I am considering adding the adj gas block and going low mass direction. Is it worth adding these components to my Stag or just build up a new rifle? I also noticed the JP offers the silent captured spring with different spring rates for those w/o adj gas blocks. Would that suffice? I guess what i need to know is the difference in weight terms between the buffer and spring rate vs a shaved down low mass bolt? Which is the larger contributor to the softer recoil?

[MarkCO]

A low mass bolt is the single largest contributor to recoil management from a parts perspective. If you are running a carbine buffer, you can remove weights and get the same affect as going with an SCS for a lot less money. Just have to remember it is a system.

The beauty of the SCS and the adjustable gas is that it makes the tuning easier and faster, but they are by no means necessary if you know what you are doing and do not mind some tinkering. The low mass carrier...can't really tinker your way into that one. I recommend the JP carrier and the Voodoo carrier due to the design and durability issues.

After that, you have to cut the gas. Your options are a barrel with the a reduced size gas port like the Nordic, or adjustable gas. I am testing an SLR, but the others, I do not have the faith in them long term. I am continually amazed at how many guys are running Nordic barrels with an adjustable gas block...wide open. On larger calibers or with charge weights north of 25 grains, yes, tuning with gas might be beneficial, otherwise, we tune with mass on the Nordic barrels.

When I ran barrels with gas ports that resulted in significant over-gassing, I did run adjustable gas.

[Jesse Tischauser]

this is perfect timing....I run a stag 3G with a Miculek brake. I reload but a mild load for my area matches. I am considering adding the adj gas block and going low mass direction. Is it worth adding these components to my Stag or just build up a new rifle? I also noticed the JP offers the silent captured spring with different spring rates for those w/o adj gas blocks. Would that suffice? I guess what i need to know is the difference in weight terms between the buffer and spring rate vs a shaved down low mass bolt? Which is the larger contributor to the softer recoil?

Stag 3G is a perfect host. Kalani and I have been running the 3G with the Seekins comp, Seekins gas block, Boomfab bcg and JP buffer/carbine bugfer.

[Jesse Tischauser]

A low mass bolt is the single largest contributor to recoil management from a parts perspective. If you are running a carbine buffer, you can remove weights and get the same affect as going with an SCS for a lot less money. Just have to remember it is a system.

The beauty of the SCS and the adjustable gas is that it makes the tuning easier and faster, but they are by no means necessary if you know what you are doing and do not mind some tinkering. The low mass carrier...can't really tinker your way into that one. I recommend the JP carrier and the Voodoo carrier due to the design and durability issues.

After that, you have to cut the gas. Your options are a barrel with the a reduced size gas port like the Nordic, or adjustable gas. I am testing an SLR, but the others, I do not have the faith in them long term. I am continually amazed at how many guys are running Nordic barrels with an adjustable gas block...wide open. On larger calibers or with charge weights north of 25 grains, yes, tuning with gas might be beneficial, otherwise, we tune with mass on the Nordic barrels.

When I ran barrels with gas ports that resulted in significant over-gassing, I did run adjustable gas.

What is the difference in his port hole size?

[Oskino]

A low mass bolt is the single largest contributor to recoil management from a parts perspective. If you are running a carbine buffer, you can remove weights and get the same affect as going with an SCS for a lot less money. Just have to remember it is a system.

The beauty of the SCS and the adjustable gas is that it makes the tuning easier and faster, but they are by no means necessary if you know what you are doing and do not mind some tinkering. The low mass carrier...can't really tinker your way into that one. I recommend the JP carrier and the Voodoo carrier due to the design and durability issues.

After that, you have to cut the gas. Your options are a barrel with the a reduced size gas port like the Nordic, or adjustable gas. I am testing an SLR, but the others, I do not have the faith in them long term. I am continually amazed at how many guys are running Nordic barrels with an adjustable gas block...wide open. On larger calibers or with charge weights north of 25 grains, yes, tuning with gas might be beneficial, otherwise, we tune with mass on the Nordic barrels.

When I ran barrels with gas ports that resulted in significant over-gassing, I did run adjustable gas.

Mark and original OP thanks for all the GREAT INFO, Mark I am def a rookie when it comes to this style of shooting but I'm hungry and want to learn as much as I can about it. With your commment on "how many guys are running Nordic barrels with an adjustable gas block...wide open." are you stating that an adjustable gas block is not needed with the Nordic?? My Voodoo carrier is suppose to be delivered this Thursday and I plan on just removing weights from my carbine buffer to achieve 3 oz or so. Then gonna head to the range and attempt to tune it. Doubles at 50 in the A zone is my goal.