Tuning an AR-15 for double taps?

[justeric]

I like action shooting competitions using an AR-15. I noticed at least half the competitors shoot each target two times with sub second split times. I find that when I shoot, I have to force the gun back on target or my second shot ends up out of the kill zone and sometimes off the paper. One of the top competitors let me shoot his gun and it stayed on target shot after shot. I was able to double tap with just a little effort. I would like to tune my AR so it stays on target from shot to shot.

I am going to install a SJC Titan muzzle break. I think it is regarded as one of the better breaks to keep your muzzle flip to a minimum. I am also considering changing my buffer and buffer spring. When I put my gun together I bought whatever buffer and spring combo was at the store. I suspect my buffer and spring are for a carbine and I am shooting a rifle length gas system.

Does anyone have suggestions on a good buffer and spring combination for a rifle length gas system? My gas port is not adjustable. I will be shooting 55 grain 223 bullets at an average velocity. I would like it tuned for 55 grain bullets but I will also be shooting 77 grain bullets that need to cycle OK. The barrel is an 18 inch 1 in 8 twist SS barrel. The upper is a Stag Arms 3g upper.

Please let me know if you have any suggestions,
Eric

 

[Copper]

Try an H2 buffer and a functional brake. Check out this video for brakes https://www.youtube.com/watch?v=3FD-Rou9-9A

 

[clandestine]

I doubt you will find a person that can tell you what buffer and spring to use, for that combination. There is too many variables such as:

Gas Port Size
Dwell Time
Barrel Diamater @ Gas Block Journal
Muzzle Device
Gas System Efficiency (F.S.B./Gas Block blowby)
Carrier Type (Lightweight, AR15, M16)
Ammunition (There is a million combinations and they all effect Gas Port Pressure, and the 2 you listed make is VERY difficult to run with optimum efficiency with both ammo choices you listed.)

If you want LOW recoil, you need LOW MASS. Low MASS operating parts means the gun probably wont run when fouled heavily or not lubricated well.

Light Carrier (Titanium or a MILLED Steel Carrier lightens MASS and reduces recoil)
Light Buffer (Lightens MASS and reduces recoil)
Flat Wire Action Spring (Eliminates Spring Stacking, and has a life cycle of 500K rounds)
Adjustable Gas (Click Adjustable Gas, SLR is the best in the game)
Side Ported Muzzle Brake (No ports on top)
A reliable trigger with a fast lock time (Geissele is best IMO)
A Heavy Gun (Not the moving parts) will reduce recoil but will slow you down


To make is simple, you can use your current setup. All you need is a GOOD adjustable gas block, a good trigger, and a good action spring. You will find the gas block setting for the loads you use enjoy the rifle.

 

[jjsat]

Thanks for the video link Cooper I learned alittle something there.

 

[Copper]

Theres a part 2 also

 

[jimbobborg]

I'd like to know more about what lower justeric is using. Just an FYI, I can double-tap with all of my ARs. One is a purpose built 3-gun rifle, one is a short HD carbine, and the last is a 6.8 SPC build.

 

[Jackson923]

I agree with what Clandestine said. One thing to also consider is a good trigger, something single stage like CMC, Hyperfire, Geisell (sp), ALG Combat with 3.5 lb JP springs. A lot of guys run low mass bolts with adjustable gas blocks. Good mags and a clean gun with help also with ensureing good feeding of ammo.

 

[pwoolford]

How are you holding your AR? I find a longer hand guard and getting my offhand further out helps too.

 

[justeric]

I'd like to know more about what lower justeric is using. Just an FYI, I can double-tap with all of my ARs. One is a purpose built 3-gun rifle, one is a short HD carbine, and the last is a 6.8 SPC build.

I wish I could tell you more about my lower. I'm using a Hyperfire trigger. I don't know what type of buffer and buffer spring I am using. When I put the lower together I bought a buffer/buffer spring kit at Bass Pro. I suspect the kit was intended for a carbine or mid length gas system. I don't have the box and I don't think the parts have any identifying marks. Maybe I can tell something by the size of the buffer and or spring?

Thanks

 

[teratos]

http://www.mdshooters.com/showthread.php?t=158158

 

[justeric]

How are you holding your AR? I find a longer hand guard and getting my offhand further out helps too.

I have a long Samson hand guard that I hold with my left hand extended and use a C-clamp or point my thumb forward. I hold the gun with my right hand with enough pressure so I can hold the gun up with just it. I pull the gun into my shoulder with my left hand. I use my left hand for aiming and holding the barrel on target when I shoot. At least that is how I try to do everything. It's easier said then done when you hear beeeeep to start the stage. Maybe practice is the key. I would like to take advantage of as many mechanical advantages as possible without causing reliability issues.

 

[jimbobborg]

I wish I could tell you more about my lower. I'm using a Hyperfire trigger. I don't know what type of buffer and buffer spring I am using. When I put the lower together I bought a buffer/buffer spring kit at Bass Pro. I suspect the kit was intended for a carbine or mid length gas system. I don't have the box and I don't think the parts have any identifying marks. Maybe I can tell something by the size of the buffer and or spring?

Thanks

If the buffer isn't marked, it's a standard weight carbine buffer. The heavier ones are marked.

I'm using a standard carbine buffer and spring with my 3-gun AR and am not having problems with double-taps. No fancy BCGs, just standard M16 BCGs. Your upper should be just right for 3-gun, maybe it's technique?

 

[Broncolou]

All like Clandestine said......
cheapeast plan in stages...
1. Good brake
2. adjustable gas system that works with both types of ammo(check hot and cold)
3.then lightened parts

I have all rifle length stuff. I run a JP Cooley brake, armalite adjustable gas block, and a standard rifle buffer with the weights drilled out and down to about 3.5 oz. It feels nice but it's no comparison to a full lightened BCG and supporting components. Good luck.

 

[photoracer]

I like action shooting competitions using an AR-15. I noticed at least half the competitors shoot each target two times with sub second split times. I find that when I shoot, I have to force the gun back on target or my second shot ends up out of the kill zone and sometimes off the paper. One of the top competitors let me shoot his gun and it stayed on target shot after shot. I was able to double tap with just a little effort. I would like to tune my AR so it stays on target from shot to shot.

I am going to install a SJC Titan muzzle break. I think it is regarded as one of the better breaks to keep your muzzle flip to a minimum. I am also considering changing my buffer and buffer spring. When I put my gun together I bought whatever buffer and spring combo was at the store. I suspect my buffer and spring are for a carbine and I am shooting a rifle length gas system.

Does anyone have suggestions on a good buffer and spring combination for a rifle length gas system? My gas port is not adjustable. I will be shooting 55 grain 223 bullets at an average velocity. I would like it tuned for 55 grain bullets but I will also be shooting 77 grain bullets that need to cycle OK. The barrel is an 18 inch 1 in 8 twist SS barrel. The upper is a Stag Arms 3g upper.

Please let me know if you have any suggestions,
Eric

I started out with a Stag 3G upper also. I checked out the muzzle brake/comp test that is on line at the time to find out which tested comps actually worked to reduce muzzle flip and recoil. The best bang for the buck was the Jerry Miceluk brake which had something like 85% of the performance of the expensive ones at 1/3 the price. I found out the straight linear brakes were not worth the money spent (at least for muzzle flip). But in reality anything with 3 big ports on each side and a few small holes on top will do the job. Don't use the Stag Comp because it actually works so good it drives the barrel down (all the Stag sponsored shooters went to other designs about the time I started shooting). On the other hand these days the only Stag part left in the gun is the barrel. Most mods were for weight reduction and other reasons. Still the barrel is good enough to hit steel at 400 yards using 1-4x optics and cheap Wal-Mart Federal 55g .223 value packs so what else do you need to get the job done? When I built the lower I started with a Geissele S3G and have never changed, even though I have a couple of other ARs with JP and Timney triggers in them.
Sub second double taps should be in the .3 range at least. You should be able to dump a 30 round mag in something like 4.5 seconds or so. Assuming you can pull the trigger that fast. Some guys triple tap just to make sure the target is dead. I don't unless its a longer paper shot.
My buffer and spring is just the standard stuff, and works good with the mid-length Stag gas system. I find I do well without an adjustable block. I use an AP Custom extended rifle length carbon fiber handguard (15") w/top rail. I tried a few of the grip aids at the end of it but ended up just leaving it bare mostly with a small rail on the bottom near the front in case I am shooting Open Division (bipod allowed). I pretty much use the grip that BJ Norris uses with the thumb over the top of the handguard (I use Ergo flush mount rail protectors to keep my support hand from getting abrasions from the rails).

 

[outrider58]

OP, I curious as to what kind of trigger your friend had in his rifle. Single or two stage. Take a good look at JPE Easy trigger syst.

http://www.jprifles.com/buy.php?item=JPFCP-1EZ

 

[dtmeyers]

Franklin Armory BFS trigger

Fires once when you pull the trigger, once when you release the trigger - not sure if it's for sale yet

http://www.recoilweb.com/franklin-armory-releases-binary-firing-system-73759.html

 

[justeric]

Thanks to everyone that responded!

 

[JoeBobOutfitters.com]

A trigger like a Hiperfire 24C and a good muzzle brake (lots of good options out there) will help with double taps. I like the Timney & Hiperfire triggers for 3gun use. IMO, they have a shorter reset than the CMC so they're easier for me to double tap targets.

Fires once when you pull the trigger, once when you release the trigger - not sure if it's for sale yet

http://www.recoilweb.com/franklin-armory-releases-binary-firing-system-73759.html

That seems like a horrible idea for 3gun or most other uses for a rifle. I wouldn't want more than one shot per trigger pull (or release). Its far too easy to have a negligent discharge otherwise. Even my O/U trap gun I converted back from a Pull/Release to a Pull/Pull to keep muscle memory the same across platforms.

 

[justeric]

Update on my double taps. I'm using a JM muzzle break and fixed my timing on the break. I was double taping from about 20 yards away and could keep most within a 8 inch circle. I had another guy that has tuned his gun with a muzzle break give mine a shot. He was able to improve on my group and said my gun is staying on target. I guess the problem for me is the nut behind the gun. As Ron Swanson would say, Be A Man. I'm going to work on my hold and hope to be double tapping soon.

Thanks to everyone for their input!
Eric

 

[photoracer]

Update on my double taps. I'm using a JM muzzle break and fixed my timing on the break. I was double taping from about 20 yards away and could keep most within a 8 inch circle. I had another guy that has tuned his gun with a muzzle break give mine a shot. He was able to improve on my group and said my gun is staying on target. I guess the problem for me is the nut behind the gun. As Ron Swanson would say, Be A Man. I'm going to work on my hold and hope to be double tapping soon.

Thanks to everyone for their input!
Eric

The hold is everything in 3-gun.