Small Frame Reciever Set Opinion

[Clint H]

Looking for opinions from the experienced gas gun shooters on how important monolithic-style uppers are for a precision 5.56 build.

Looking to start my first precision-minded build mostly for fun/ maybe some competition in the future. Debating between choosing a Mega set (proprietary handguard that mounts to upper, tight lock-up, thermal fit) vs an ADM or Radian set (full ambi, non-thermal, traditional handguard mount off the barrel nut).

How would you weight the importance of features in your experience?

Or alternatively, anyone ever put a Mega upper on a ADM lower?

Thanks,
Clint

 

[Leicafan1990]

That semi-monolithic Mega upper isn’t actually as rigid as people assume it is. If you want the benefits of monolithic uppers, you need to go the LMT route.

Honestly though, any good thermal fit upper with a very rigid rail is going to be a great foundation for an accurate build. If you want to go with MLok, the SOLGW/Icon Defense Drivelock rail is probably the most rigid at the moment. Pair that with any quality billet or forged upper and you are set.

Out of the box thermal fit uppers like BCM, Mega and SOLGW are the most convenient but any upper can be made to be thermal fit with shim stock or Loctite 620.

If you care about aesthetics and very little wobble between the upper and lower, you can get matched sets but it’s not really important for accuracy so guys mix and match uppers and lowers all the time.

 

[BCP]

Plain old Aero uppers and lowers have a little tensioning thing for lockup. A quality handguard, barrel and basic milspec phosphate bcg will get you 95% of the way there.

 

[Clint H]

That semi-monolithic Mega upper isn’t actually as rigid as people assume it is.

Thanks for that, I was wondering. I see them mentioned quite a bit, but didn't know what the fit was actually like.

 

[msgriff]

There are some rail deflection tests out there, if that's your concern. I do like this design, but it's proprietary:

 

[Clint H]

There are some rail deflection tests out there, if that's your concern. I do like this design, but it's proprietary:

What manufacturer is that?

I wouldn't say it's a concern, just wanted to pick everyone's brain on if that should be a primary concern on a small frame setup.

 

[bigjake83]

That semi-monolithic Mega upper isn’t actually as rigid as people assume it is.

I 100% disagree with this statement and it's obvious that you are not being through in your part selections.

 

[Leicafan1990]

Thanks for that, I was wondering. I see them mentioned quite a bit, but didn't know what the fit was actually like.

I’m talking specifically about the rigidity of the rail which really isn’t that much of a concern unless you are running a IR laser on the end of the rail. You could still build a super accurate gun with it, no doubt. But you aren’t really getting any benefits from the Mega semi monolithic that will help with accuracy.

 

[msgriff]

What manufacturer is that?

I wouldn't say it's a concern, just wanted to pick everyone's brain on if that should be a primary concern on a small frame setup.

Newtown Firearms, goes by NF now.

 

[Leicafan1990]

I 100% disagree with this statement and it's obvious that you are not being through in your part selections.

This is referring to the small frame Mega semi monolithic upper. People just assume that it is super rigid because the rail bolts to the upper itself but there was a deflection test, I think it was on Primary & Secondary and it actually lost out to a few rails that were traditional barrel nut designs. Mike Miller at Icon even said his new Drivelock system was more rigid and he would know since he designed the Mega receiver sets.

 

[bigjake83]

I’m talking specifically about the rigidity of the rail which really isn’t that much of a concern unless you are running a IR laser on the end of the rail. You could still build a super accurate gun with it, no doubt. But you aren’t really getting any benefits from the Mega semi monolithic that will help with accuracy.

Again you are wrong, the added material forward of the dust cover increases the surface area and rigidity of that upper receiver easily by 200%

 

[BCP]

Newtown Firearms, goes by NF now.

IIRC they used to be in placerville and made a sort of knock-off POF piston type rifle. Haven't heard of them in awhile.

Another to throw in the mix is the larue upper. He sells them with the 13" mlok handguard for 489. No idea on stock status.

 

[B Man]

This is referring to the small frame Mega semi monolithic upper. People just assume that it is super rigid because the rail bolts to the upper itself but there was a deflection test, I think it was on Primary & Secondary and it actually lost out to a few rails that were traditional barrel nut designs. Mike Miller at Icon even said his new Drivelock system was more rigid and he would know since he designed the Mega receiver sets.

Do you have this test to share? I have seen one (didn’t have mega) but had Aero enhaced and Seekins that only performed under the LMT full monolithic design with the Seekins extremely close to the lmt. But out performed every other set that was the normal handguard to barrel nut design by a fair margin. I’ll see if I can find it, but I am curious of the test with the mega set too.

 

[B Man]

That was easier to find than I expected.

Rigidity Matters: Testing Popular Rails to Find Zero Retention for IR Lasers

For those who use a rail-mounted front sight or a visible/IR laser attached to a rail, rigidity and return to zero play a huge factor in getting accurate shot placement downrange.

www.gunsamerica.com

but still curious of the Mega MML test you read.

 

[bigjake83]

And that is just one of the many reasons why I chose the Seekins Precision SP3R V3 (with iRMT-3 Upper) for this build and I even took it 4 steps further for increasing rigidity, fitment and barrel harmonics.

These were the first two 5rd groups shot while conducting barrel break-in, in-between shots as while making gas block and muzzle break adjustments using Blackhills 77.

 

[Leicafan1990]

Again you are wrong, the added material forward of the dust cover increases the surface area and rigidity of that upper receiver easily by 200%

View attachment 8204095

The upper receiver itself is extremely rigid. As you said, the extra material adds a lot of strength but the weakness is the rail itself. According to the guy who designed it, they had use a thinner extrusion because of the increased inner diameter required by the design. I’ll see if I can find this deflection test again. I think it was on Primary & Secondary but this is probably like 8 or 9 years ago. From what I recall, the small frame Mega semi monolithic had more flex than the NV guys would have liked and I recall the DD RIS 2 having noticeably less flex.

But I could see the extra meat on the Mega upper being beneficial on builds that use a 20”+ heavy profile barrel. But if your using a 16” medium profile barrel, I really don’t think you gain much from using the Mega MML. You are stuck using that proprietary rail and with an inner diameter of 1.5”, its pretty chunky.

I know Seekins has a similar design that is supposed to be extremely strong. My comments aren’t meant to dismiss the design as a whole.

 

[Leicafan1990]

And that is just one of the many reasons why I chose the Seekins Precision SP3R V3 (with iRMT-3 Upper) for this build and I even took it 4 steps further for increasing rigidity, fitment and barrel harmonics.

These were the first two 5rd groups shot while conducting barrel break-in, in-between shots as while making gas block and muzzle break adjustments using Blackhills 77.

View attachment 8204137View attachment 8204136View attachment 8204135

What were the 4 further steps? Also, how does that home plate shaped rail feel in the hands? It looks like it would be awkward to wrap your hand around it but I’ve never tried it so I’m genuinely curious. Sweet build.

 

[TheOE800]

Thanks for that, I was wondering. I see them mentioned quite a bit, but didn't know what the fit was actually like.

Don’t worry about him. The Mega is plenty rigid and 7075, so it’s ahead of every single two piece upper/rail combo out there for our purposes with much better QC and off the shelf barrel compatibility.

That was easier to find than I expected.

Rigidity Matters: Testing Popular Rails to Find Zero Retention for IR Lasers

For those who use a rail-mounted front sight or a visible/IR laser attached to a rail, rigidity and return to zero play a huge factor in getting accurate shot placement downrange.

www.gunsamerica.com

but still curious of the Mega MML test you read.

Of note in this experiment would be the upper receiver’s effect on deflection as shown by the Seekins rail with and without matching upper. M4C knew this well over 10 years ago when measuring barrel droop and deflection of flat-top receivers against carry handles - we lost a fair amount of receiver rigidity in that transition. And of course as the receiver heats up this effect is more pronounced. Enhanced and billet uppers with thicker walls mitigate this condition to some extent, which is a big deal to us with long heavy barrels.

 

[bigjake83]

What were the 4 further steps? Also, how does that home plate shaped rail feel in the hands? It looks like it would be awkward to wrap your hand around it but I’ve never tried it so I’m genuinely curious. Sweet build.

Sorry Jr. You're on you own. I'm no going to keep spoon feeding from my hands on real world knowledge. It's clear that your knowledge is literature based only, and that's why just about every single damn thread you've ever posted on here is you asking for help or advice.

You clearly have no idea what you're talking concerning The Mega Receiver options, you admitted that your knowledge on matter only came from some jerkoff article your read from 8-9 years ago.

My advice, keep your head down and your ears open and stop trying to give advice on subjects unless you yourself have actual hands on experience with.

 

[Leicafan1990]

Sorry Jr. You're on you own. I'm no going to keep spoon feeding from my hands on real world knowledge. It's clear that your knowledge is literature based only, and that's why just about every single damn thread you've ever posted on here is you asking for help or advice.

You clearly have no idea what you're talking concerning The Mega Receiver options, you admitted that your knowledge on matter only came from some jerkoff article your read from 8-9 years ago.

My advice, keep your head down and your ears open and stop trying to give advice on subjects unless you yourself have actual hands on experience with.

I don’t know what your problem is man. This is like the 2nd or 3rd time you’ve personally attacked me because I said something you disagreed with. Other than some adjustable gas block recommendations, I don’t ever recall you spoon feeding me advice. I get it Jake, you think you are the best gas gun builder on the Hide and you probably are but you don’t need to be so arrogant about it.

The guy who designed the original Mega MML has said that his newer Drivelock design has less deflection. That’s all I’m saying. I have said absolutely nothing about the Seekins system or any of the other companies that offer semi monolithic uppers like Aero and Cobalt Kinetics.

I would greatly appreciate it if you could respond to my comments without being rude and condescending.

 

[Clint H]

Sorry everyone, I didn't mean to open a can-of-worms with this question.

Appreciate all the feedback, though.

Here's the only other resource I was able to find on handguard POI shift, but it's limited to a handful of rails and geared more toward running lasers/night vision.

Resources – Nocturnality

www.nocturnalitygear.com

 

[msgriff]

Sorry everyone, I didn't mean to open a can-of-worms with this question.

Appreciate all the feedback, though.

Here's the only other resource I was able to find on handguard POI shift, but it's limited to a handful of rails and geared more toward running lasers/night vision.

Resources – Nocturnality

www.nocturnalitygear.com

This one is my favorite test.

 

[bigjake83]

I don’t know what your problem is man. This is like the 2nd or 3rd time you’ve personally attacked me because I said something you disagreed with. Other than some adjustable gas block recommendations, I don’t ever recall you spoon feeding me advice. I get it Jake, you think you are the best gas gun builder on the Hide and you probably are but you don’t need to be so arrogant about it.

The guy who designed the original Mega MML has said that his newer Drivelock design has less deflection. That’s all I’m saying. I have said absolutely nothing about the Seekins system or any of the other companies that offer semi monolithic uppers like Aero and Cobalt Kinetics.

I would greatly appreciate it if you could respond to my comments without being rude and condescending.

I'm not attacking you, Im a very direct person so if the manner in which I speak seems callous and arrogant I apologize but you're giving advice to people who are trying to make a informative purchase decision with incorrect information. And your blanket statement about the quality and rigidity of the MEGA AR15 MML Billet Upper Receiver is completely incorrect..

And in reference to your "DriveLock" design are you referring to the wedged lock design that Mega and Hodge defense came up with?? If so that’s a completely different animal and is designed for conventional Milspec Style upper receivers not the extended MML design with the Intergral Nut.

 

[Clint H]

This one is my favorite test.

Is that the 2020 ammo shortage simulation test? "How well does it work as a club because I got no bullets?"

 

[Leicafan1990]

I'm not attacking you, Im a very direct person so if the manner in which I speak seems callous and arrogant I apologize but you're giving advice to people who are trying to make a informative purchase decision with incorrect information. And your blanket statement about the quality and rigidity of the MEGA AR15 MML Billet Upper Receiver is completely incorrect..

And in reference to your "DriveLock" design are you referring to the wedged lock design that Mega and Hodge defense came up with?? If so that’s a completely different animal and is designed for conventional Milspec Style upper receivers no the extended MML design with the Intergral Nut.

I don’t see how my posting history from when I first joined this forum is at all relevant to this discussion. You can tell me I’m wrong without injecting that into the discussion.

Anyways, I’m not at all questioning the quality of Mega products. I own stuff from Mega and ZEV and I can attest to their quality being absolutely top notch. My first AR lower was a Mega Gator and it has a ton of sentimental value to me so I will always be a Mega fan.

I’m not disputing that semi monolithic uppers like the Mega MML and the Seekins are more rigid (the upper receiver itself, not necessarily the rail as well). Obviously having more material where the barrel seats into the upper is going to increase rigidity. I can absolutely see that extra meat being beneficial on receivers with long, heavy barrels.

But if we are talking about upper rigidity, we also need to consider the rigidity of the rail as well and in my opinion, a semi monolithic upper doesn’t always result in a more rigid rail. Yes, the Seekins is probably the most rigid two piece design out there but that doesn’t mean that every single semi monolithic design beats every single traditional barrel nut rail in terms of rigidity. That’s really what I was trying to say but I didn’t do a good job of conveying that clearly.

We’ve had links to two published rail deflection tests and in both cases, a traditional barrel nut design equaled or narrowly beat a semi monolithic design. In the first test, the Aero M4E1 Enhanced was just barely beat in the deflection test by the Ripcord LDR1 and in the impact test, the DD RIS 3 has less shift than the Aero. In the second test, the Larue Stealth performed similarly to traditional barrel nut rails.

The Drivelock is basically Gen.3 of the Mike Miller rail designs. He designed the original Wedgelock rails when he was with Mega and then helped Hodge with the Pinchlock design. Then he came out with the Drivelock rail he developed with SOLGW and he says it’s the strongest rail he’s developed so far. The Drivelock is sold by his new company Icon Defense and SOLGW.

 

[JS8588]

I don’t see how my posting history from when I first joined this forum is at all relevant to this discussion. You can tell me I’m wrong without injecting that into the discussion.

Anyways, I’m not at all questioning the quality of Mega products. I own stuff from Mega and ZEV and I can attest to their quality being absolutely top notch. My first AR lower was a Mega Gator and it has a ton of sentimental value to me so I will always be a Mega fan.

I’m not disputing that semi monolithic uppers like the Mega MML and the Seekins are more rigid (the upper receiver itself, not necessarily the rail as well). Obviously having more material where the barrel seats into the upper is going to increase rigidity. I can absolutely see that extra meat being beneficial on receivers with long, heavy barrels.

But if we are talking about upper rigidity, we also need to consider the rigidity of the rail as well and in my opinion, a semi monolithic upper doesn’t always result in the most rigid rail. Yes, the Seekins is probably the most rigid two piece design out there but that doesn’t mean that every single semi monolithic design beats every single traditional barrel nut rail in terms of rigidity. That’s really what I was trying to say but I didn’t do a good job of conveying that clearly.

We’ve had links to two published rail deflection tests and in both cases, a traditional barrel nut design equaled or narrowly beat a semi monolithic design. In the first test, the Aero M4E1 Enhanced was just barely beat in the deflection test by the Ripcord LDR1 and in the impact test, the DD RIS 3 has less shift than the Aero. In the second test, the Larue Stealth performed similarly to traditional barrel nut rails.

The Drivelock is basically Gen.3 of the Mike Miller rail designs. He designed the original Wedgelock rails when he was with Mega and then helped Hodge with the Pinchlock design. Then he came out with the Drivelock rail he developed with SOLGW and he says it’s the strongest rail he’s developed so far. The Drivelock is sold by his new company Icon Defense and SOLGW.

The Icon Drivelock rails are 6061, the SOLGW rails are 7075

 

[Leicafan1990]

The Icon Drivelock rails are 6061, the SOLGW rails are 7075

Where did you read this? My understanding is that the only difference between them is the steel barrel nut on the SOLGW and the Titanium barrel nut on the Icon.

 

[B Man]

I don’t see how my posting history from when I first joined this forum is at all relevant to this discussion. You can tell me I’m wrong without injecting that into the discussion.

Anyways, I’m not at all questioning the quality of Mega products. I own stuff from Mega and ZEV and I can attest to their quality being absolutely top notch. My first AR lower was a Mega Gator and it has a ton of sentimental value to me so I will always be a Mega fan.

I’m not disputing that semi monolithic uppers like the Mega MML and the Seekins are more rigid (the upper receiver itself, not necessarily the rail as well). Obviously having more material where the barrel seats into the upper is going to increase rigidity. I can absolutely see that extra meat being beneficial on receivers with long, heavy barrels.

But if we are talking about upper rigidity, we also need to consider the rigidity of the rail as well and in my opinion, a semi monolithic upper doesn’t always result in the most rigid rail. Yes, the Seekins is probably the most rigid two piece design out there but that doesn’t mean that every single semi monolithic design beats every single traditional barrel nut rail in terms of rigidity. That’s really what I was trying to say but I didn’t do a good job of conveying that clearly.

We’ve had links to two published rail deflection tests and in both cases, a traditional barrel nut design equaled or narrowly beat a semi monolithic design. In the first test, the Aero M4E1 Enhanced was just barely beat in the deflection test by the Ripcord LDR1 and in the impact test, the DD RIS 3 has less shift than the Aero. In the second test, the Larue Stealth performed similarly to traditional barrel nut rails.

The Drivelock is basically Gen.3 of the Mike Miller rail designs. He designed the original Wedgelock rails when he was with Mega and then helped Hodge with the Pinchlock design. Then he came out with the Drivelock rail he developed with SOLGW and he says it’s the strongest rail he’s developed so far. The Drivelock is sold by his new company Icon Defense and SOLGW.

I own Aero enhanced uppers/handguards and Mega’s MML. There is no comparison of the upper or rails rigidity between the two. That’s is not a knock on Aero, they have made accurate builds for me and have a place, but the Upper is much thicker on Mega and the hand guard is 7075 on the mega, almost twice as thick in material, and the fitment of the hand guard to the upper is something to personally see and use to understand how tight it is. Without attachment screws the aero will wobble when slid on requiring the screws to stabilize it, with the Mega when you slip it on you have to practically ask it nicely to let go to take it back off. The aero enhanced sets are better than most normal handguard to barrel nut systems, but no comparison of the Mega’s that has built the most consistent accurate rifle I have thus far shooting bench or prone that I believe is helped by the design.

 

[JS8588]

Where did you read this? My understanding is that the only difference between them is the steel barrel nut on the SOLGW and the Titanium barrel nut on the Icon.

Drive Lock™ Hand Guard - Icon Defense

Material: 6061 T6 Aluminum Coating: Type 3 Hard Coat Anodize ID 1.39" OD 1.69" Hand Guard Fully Assembled (11.2 oz - 1 lb ) Drive Lock Barrel Nut Material: Titanium Weight: 2.2 oz

www.icondefense.com

And SOLGW confirmed for me directly theirs are 7075

 

[Clint H]

I own Aero enhanced uppers/handguards and Mega’s MML. There is no comparison of the upper or rails rigidity between the two.


View attachment 8204644

Nice! The matching lines make that look like a really clean build.

The Aero comparison is what made me question the Mega design a bit. I've done a couple Aero builds as more of a general purpose rifle and their tolerances seem to run pretty loose. One upper/barrel took a .003" shim just to take up the slop (not even to get interference fit). Same with an Atlas handguard.

Like you said, nothing against them for what they are. I just wanted something tighter as a base for a precision build since it seems like inaccuracies stack in this game.

 

[B Man]

Nice! The matching lines make that look like a really clean build.

The Aero comparison is what made me question the Mega design a bit. I've done a couple Aero builds as more of a general purpose rifle and their tolerances seem to run pretty loose. One upper/barrel took a .003" shim just to take up the slop (not even to get interference fit). Same with an Atlas handguard.

Like you said, nothing against them for what they are. I just wanted something tighter as a base for a precision build since it seems like inaccuracies stack in this game.

Unless they slip and let a bad one out I would buy with confidence and worry about something else in the build for accuracy. You can leave the shim stock and loctite 620 shelved for a different set. I’ve been down that road too.

 

[TonyTheTiger]

Also, how does that home plate shaped rail feel in the hands? It looks like it would be awkward to wrap your hand around

Terrible. I have one and I like it, just not for holding on to.

 

[msgriff]

Is that the 2020 ammo shortage simulation test? "How well does it work as a club because I got no bullets?"

There's a pretty funny story behind that clip. That's Bill Geissele reacting to someone dissing his handguard attachment design. The full video is cringe.

 

[MontanaMan]

SanTan, Cross Machine Tool, SLR, V-7.

If you can't find something you like there, you too picky.

MM

 

[B Man]

SanTan, Cross Machine Tool, SLR, V-7.

If you can't find something you like there, you too picky.

MM

V7 has gotten my attention