Improving the precision of an AR

[SteveOak]

I am thinking about having an AR built for a local match.

A monolithic upper would eliminate shifting of the hand guard but they complicate barrel installation and limit choices.

Is there another way? Yankee Hill used to make a 11.25" long rail riser. You could run that from the Pic rail on the reciever to the pic rail on the handguard to lash them together when using a front rest.

Unfortunately, Yankee Hill no longer makes the long riser and I don't seem to be able to find one.

Any ideas how to lash the receiver and handguard together?

Thanks!

 

[VA_XTC_Shooter]

Why would you want the upper tied to the handguard more than it is? You're then transferring any pressure on handguard to the scope mount.

 

[Konocti's Wigwam]

I think that should be handled at the barrel nut. The newer hand guard clamp onto the barrel nut, which doesn't use shims. I guess the questions is what type of hand guard do you currently have? The older style that used shims and the muiti-spanner wrench to tighten/loosen screws down pretty tight there.

I would look to White Oak Armament for precision ARs. Some competitions require a service rifle, don't forget to check your local.

EDIT: Sorry to follow up on myself, but in looking at their handguards, they do use the newer clamp style. I don't know the difference between the old and new, but this newer style saves a lot of time in getting things clocked correctly. I have both styles and both work for me.

With the new wrenchless muzzle devices, it really does seem to simplify things. That goes for the gas block as well, what used to be set screws has now turned into a clamp style as well.

White Oak TR M-LOK Handguard

White Oak TR M-LOK Handguard

www.whiteoakarmament.com

damn I'm a bad speller..

 

[Fuj]

I am thinking about having an AR built for a local match.

A monolithic upper would eliminate shifting of the hand guard but they complicate barrel installation and limit choices.

I use a Rock River EOP. I did not find it complicated when I installed
the Kreiger barrel. The beauty of the EOP is being able to use a scope
with a large objective lens with short rings and clear the forearm rail,
and extra stiff also......If money is limited, they probably have a part your
looking for to suit your build.
.

 

[Rocketvapor]

Heavy wall receiver, True thermal fit.

 

[padom]

I use thermofit uppers (MEGA billetnor BCM forged), Rubber City Adjustable Gas key BCG's, and fixed low pro SS gas blocks with plenty of clearance from hitting the handguard.

Geissele, JP and SLR handguards have been rock solid

Here a new 6 ARC AR I just built and have been testing the past few weeks. Shooting really good..

https://imgur.com/KeGv1ix

https://imgur.com/XeRdVPO

 

[SteveOak]

Why would you want the upper tied to the handguard more than it is? You're then transferring any pressure on handguard to the scope mount.

I'm guess you are unfamiliar with a monolithic upper.

 

[padom]

Zev, who bought MEGA a while back has the continous top rail upper receiver/handguard combo in stock. MEGA used to do these and Seekins does similar with their IRMT-3 upper.

Essentially, for rigidity, the handguard mounting is milled right into the upper for rigidity, vs a nut...

RIFLE PARTS - ZEV Technologies

Upgrade your AR with ZEV’s premium forged and billet receivers, rifle barrels, and complete uppers. Built for maximum performance. Shop rifle parts today!

www.zevtechnologies.com

IRMT-3 Upper

<p><strong>iRMT-3 Upper</strong></p> <p>Designed for extreme accuracy and durability under real-world stress, the iRMT-3 upper receiver allows your barrel to be a true free float system. With the handguard attaching directly

seekinsprecision.com

 

[VA_XTC_Shooter]

I'm guess you are unfamiliar with a monolithic upper.

Admittedly, I totally missed "monolithic" in the OP. Disregard comment.

 

[Jeff Porter]

What type of match are you building it for ?

 

[SteveOak]

What type of match are you building it for ?

A club in the Cincinnati area has started an "AR Varmint Benchrest" match. Benchrest for score. Any gas operated AR, any cartridge, .35 cal max. Prone or portable bench, bags, bipod, or mechanical front rest. Four targets, five shots each, 20 rounds total at 300 yards.

I have an AR built on a Mega Arms ambi receiver set, 5.56, 16" barrel. I am thinking to build another rifle in 6 ARC with a 20" barrel.

The idea of a 6mm AR-15 has intrigued me but I had not previously had a sufficient reason to build one. I have 6mm bolt rifles.

 

[SteveOak]

Zev, who bought MEGA a while back has the continous top rail upper receiver/handguard combo in stock. MEGA used to do these and Seekins does similar with their IRMT-3 upper.

Essentially, for rigidity, the handguard mounting is milled right into the upper for rigidity, vs a nut...

RIFLE PARTS - ZEV Technologies

Upgrade your AR with ZEV’s premium forged and billet receivers, rifle barrels, and complete uppers. Built for maximum performance. Shop rifle parts today!

www.zevtechnologies.com

IRMT-3 Upper

<p><strong>iRMT-3 Upper</strong></p> <p>Designed for extreme accuracy and durability under real-world stress, the iRMT-3 upper receiver allows your barrel to be a true free float system. With the handguard attaching directly

seekinsprecision.com

Yeah, I have been looking at the MEGA.

I have an AR built on a MEGA AR15 billet GTR-3H receiver set that I like. I send Zev an email Friday, asking if the monolithic upper is compatible with the ambi lower.

 

[gunsandgunsmithing]

A club in the Cincinnati area has started an "AR Varmint Benchrest" match. Benchrest for score. Any gas operated AR, any cartridge, .35 cal max. Prone or portable bench, bags, bipod, or mechanical front rest. Four targets, five shots each, 20 rounds total at 300 yards.

I have an AR built on a Mega Arms ambi receiver set, 5.56, 16" barrel. I am thinking to build another rifle in 6 ARC with a 20" barrel.

The idea of a 6mm AR-15 has intrigued me but I had not previously had a sufficient reason to build one. I have 6mm bolt rifles.

If IBS targets, you might consider a 30 Major(grendel). I've built them for this very purpose. A club in southern In started a similar match. I built an upper for a guy up there in 30 Major. He NEVER lost a match. They stopped holding them.
I've done a few for this purpose and different clubs have different rules. This one, had to be all AR15 but did not have to cycle, so I didn't even put a gas port in the bbl. I never would of believed it but, he was able to shoot my hot bolt gun loads in it with no bolt failures. I presume due to good contact and the bolt didn't rotate under pressure with no gas system. Same Grendel bolt that you read about failures with and reduced gas gun data with. fwiw.
The best I've been able to get a functioning AR to reliably shoot is low to mid .3's. Not bad but his non-functioning rifle way outperformed that. I'm talking agg'ing ability, not every once in a while groups.

He shot against a few 6 PPC ar's in that class but they simply left too much on the table due to a 30 cal bullet hole vs a 6.

 

[Hal]

Wow I didn't know they shot that well.

Hal

 

[gunsandgunsmithing]

Wow I didn't know they shot that well.

Hal

All custom and a bit more involved than a bolt gun but yeah, they can shoot pretty well. I really don't think there's another gas gun platform out there than can hold a candle to them, if done right.

 

[SteveOak]

All custom and a bit more involved than a bolt gun but yeah, they can shoot pretty well. I really don't think there's another gas gun platform out there than can hold a candle to them, if done right.

To which gas gun platform do you refer?

Not IBS targets. They are in the shape of a gopher.

 

[jelenko]

If IBS targets, you might consider a 30 Major(grendel). I've built them for this very purpose. A club in southern In started a similar match. I built an upper for a guy up there in 30 Major. He NEVER lost a match. They stopped holding them.
I've done a few for this purpose and different clubs have different rules. This one, had to be all AR15 but did not have to cycle, so I didn't even put a gas port in the bbl. I never would of believed it but, he was able to shoot my hot bolt gun loads in it with no bolt failures. I presume due to good contact and the bolt didn't rotate under pressure with no gas system. Same Grendel bolt that you read about failures with and reduced gas gun data with. fwiw.
The best I've been able to get a functioning AR to reliably shoot is low to mid .3's. Not bad but his non-functioning rifle way outperformed that. I'm talking agg'ing ability, not every once in a while groups.

He shot against a few 6 PPC ar's in that class but they simply left too much on the table due to a 30 cal bullet hole vs a 6.

Would a monolithic upper be more accurate than an upper attached the way WOA does for varmint/match uppers?

 

[padom]

Yeah, I have been looking at the MEGA.

I have an AR built on a MEGA AR15 billet GTR-3H receiver set that I like. I send Zev an email Friday, asking if the monolithic upper is compatible with the ambi lower.

I have multiple MEGA small and large frame ambi billet sets also. I bought multiple spare sets during the ownership change on clearance for future builds..


I was hesitant to build a 6ARC build for a long time but a fast 6mm 85-95gr load sounded intriguing so I went down the rabbit hole.

I have numerous custom Precision 20" Bartlein, Krieger and Shilen 223 Wylde ARs and a few Bartlein and Krieger MEGA 308 and 6.5cm gasser.

I've been playing with 85 SMK and 87 VMAX in this 6 ARC and it's a laser. Boring accurate at 700yd I was shooting the other day.

 

[gunsandgunsmithing]

To which gas gun platform do you refer?

Not IBS targets. They are in the shape of a gopher.

Sorry..ar15. Larger bullet diameter still has the same advantage. I'd consider a 30 in any score game that isn't caliber neutral. Ie...ubr.
Any way ya shake it, the 30 still has a .065 bigger hole in the target.

 

[gunsandgunsmithing]

Would a monolithic upper be more accurate than an upper attached the way WOA does for varmint/match uppers?

Can't hurt but I honestly don't think you'll see a difference if the bbl is thermal fit or even loctited, and torqued well to the upper