Wanting to build a .5 Moa gas gun???
- Thread starter Lrdchaos
- Start date
For an AR IN 5.56 to be .5 moa or better a first time home build is not the most likely route to success.
Seekins was not the most accurate maker in my extensive testing of several dozen AR’s. Most Seekins were from .8 moa to 1.25 moa.
The most simple way to get a .5 MOA AR for certain is to purchase a Les Baer. KAC has features I prefer and many will reach your goal but will not as certain as Baer.
All group information is based on 10 shot groups off bipod.
Seekins was not the most accurate maker in my extensive testing of several dozen AR’s. Most Seekins were from .8 moa to 1.25 moa.
The most simple way to get a .5 MOA AR for certain is to purchase a Les Baer. KAC has features I prefer and many will reach your goal but will not as certain as Baer.
All group information is based on 10 shot groups off bipod.
Call Keystone Accuracy and get a 20" Kreiger barrel with rifle gas spun up in 223 Wylde and put that on either a Seekins or MEGA billet receiver set. Rubber City or JP full mass carrier, Geissele SD-E or NM trigger, JP SCS and a Superlative AGB. From there it will depend on the guy behind the gun but it will shoot for sure.
JP Enterprises will get you where you want to be.
In my experience, LaRue will come up short, but lots of fans will sing their praises. White Oak Armament I read some great and some not so great....enough to bump them from consideration in my eyes.
Others that sound promising but have not tried.
Compass Lake Engineering with a Bartlein barrel
Craddock Precision
My JP routinely does this.....all 5 round groups with commercially available/factory ammo. Copper Creek, Defender, Hornady Black.
In my experience, LaRue will come up short, but lots of fans will sing their praises. White Oak Armament I read some great and some not so great....enough to bump them from consideration in my eyes.
Others that sound promising but have not tried.
Compass Lake Engineering with a Bartlein barrel
Craddock Precision
My JP routinely does this.....all 5 round groups with commercially available/factory ammo. Copper Creek, Defender, Hornady Black.
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Buying or building a 1/2 minute AR isn't hard as long as you choose top tier components or rifles. Shooting it 1/2 minute is another story due to the lock time.
The LMT rifles with SS barrels are stupid accurate. Their chrome moly barrels are too. The KAC rifles are also top performers.
Just about any custom cut rifled barrel option from a reputable builder with a matched bolt will get you there too. I've had a few high end commercial grade barrels that shot lights out too but sub 3/4 is more the norm with them.
Trigger and grip selection made as huge difference to me as far as how well I can shoot an AR. After trying dozens of grips and a bunch of top tier triggers I determined that I shoot best with a Magpul MOE+ grip and a Geissele SD-E trigger, so my AR's all sport them.
You can also pretty much bank on having to load your own ammo to get 1/2moa out of an AR and I'm not talking cranking ammo out on a Dillon. Meticulous practices give the best results.
The LMT rifles with SS barrels are stupid accurate. Their chrome moly barrels are too. The KAC rifles are also top performers.
Just about any custom cut rifled barrel option from a reputable builder with a matched bolt will get you there too. I've had a few high end commercial grade barrels that shot lights out too but sub 3/4 is more the norm with them.
Trigger and grip selection made as huge difference to me as far as how well I can shoot an AR. After trying dozens of grips and a bunch of top tier triggers I determined that I shoot best with a Magpul MOE+ grip and a Geissele SD-E trigger, so my AR's all sport them.
You can also pretty much bank on having to load your own ammo to get 1/2moa out of an AR and I'm not talking cranking ammo out on a Dillon. Meticulous practices give the best results.
I shot their precision model once at my club.a member had just bought it. I own a few ARs and this rifle was unbelievably accurate. Fit and finish aside which was outstanding. I was able to fire all the rounds inside a dime size group. This is not a plug for the company because I own no handguns from them bu this AR was unbelievably accurate to the point of being boring only having a 100 yard range to shoot from
What style of rifle are you looking for ???
Varmint, SPR, Recon????
You can get a .5 AR in many different flavors.
What style of rifle are you looking for ???
Varmint, SPR, Recon????
You can get a .5 AR in many different flavors.
I've got Les Baer Rifles, RRA, and several Custom Jobs that shoot sub .5 MOA
A little bit more Info and I could probably hook you up.
Varmint, SPR, Recon????
You can get a .5 AR in many different flavors.
What style of rifle are you looking for ???
Varmint, SPR, Recon????
You can get a .5 AR in many different flavors.
I've got Les Baer Rifles, RRA, and several Custom Jobs that shoot sub .5 MOA
A little bit more Info and I could probably hook you up.
I've still got this one just chillin in my safe.
https://www.snipershide.com/shootin...-2-moa-ar-group-pics-up-for-the-fans.6255074/
https://www.snipershide.com/shootin...-2-moa-ar-group-pics-up-for-the-fans.6255074/
I just finished this build. It's .5 MOA. I bedded the barrel into the receiver and lapped the receiver face. Made huge difference. I didn't use super high end components. Rock River upper and lower. Rock River BCG. Wilson Arms 24" SST Fluted Barrel w/.223 Wylde Chamber. SLR adjustable gas block. It's shooting just under 1 MOA with cheap American Eagle 55 gn and 1/2 MOA with Federal Gold Medal Match.
Federal 69 gn. Gold Medal Match
55 gn American Eagle
Federal 69 gn. Gold Medal Match
55 gn American Eagle
I reload, but my LWRC does it with ease using 69smk, in a 16 inch barrel. I had them add a 16 inch barrel to a DEA model, piston gun. Only thing I changed was I added a Timney trigger.
White Oak
Keystone Accuracy
Compass Lake
...are the only ones I would even bother researching if I needed a Krieger or Bartlein to go into an AR and hope for 1/4 Minute.
They are also proud of their stuff, but not nearly friggin' Les Baer or JP proud. They also know the difference between trick parts and procedures, and what are basically just tricky parts.
Example: I have had no less than 3 sub-1/2 Minute competition uppers, and only one has anything but a mil-spec BCG. A2's too. Yeah...no billet, no full bull barrels, no gold coated BS...
...just a good barrel and good machining.
-Nate
Keystone Accuracy
Compass Lake
...are the only ones I would even bother researching if I needed a Krieger or Bartlein to go into an AR and hope for 1/4 Minute.
They are also proud of their stuff, but not nearly friggin' Les Baer or JP proud. They also know the difference between trick parts and procedures, and what are basically just tricky parts.
Example: I have had no less than 3 sub-1/2 Minute competition uppers, and only one has anything but a mil-spec BCG. A2's too. Yeah...no billet, no full bull barrels, no gold coated BS...
...just a good barrel and good machining.
-Nate
Have a few high end ARs that shoot really well but my kac sr15 lpr is a laser. If you can find one with the kreiger jump on it!
I'm waiting on a 20" Kreiger cut barrel from Compass Lake then I should be able to join this club. waiting is so damn hard.
Hey there wilson, I too have a rock river (predator pursuit) in .223. I've been wanting to convert over to .204 for a lil more accuracy and speed. My question is which is the best way? My upper and lower seem to have a bit of wobble in them. A separate PSA upper fits very tight so I imagine the upper is out of spec. Is it as simple as getting another wilson arms barrel then bed the barrel into the receiver and lapped the receiver face? Do you do such work that we can talk about?
In AR15. Platform you should check 6mmAR.com
Its a guarantee .5moa or better. I got two of their turbo 40 one with bartlein gain twist..i might sell one.check their web hit me up if you interested
Its a guarantee .5moa or better. I got two of their turbo 40 one with bartlein gain twist..i might sell one.check their web hit me up if you interested
For a budget mass produced rifle, the savage msr10 long range will do it with Hormandy 120 eld match. After that, JP will do it much sexier for 3x the money.
I have owned two Les Baer AR's. Both shot sub 1/2 MOA all day, every day with 69 grain Federal match ammo. Their is a difference between shooting a 1/2MOA group once in a while and a rifle that does it every time the shooter does his job!
yup, about a week and a half ago, just got it back from the local Cerakote pro yesterday. Now I just need to get the parts over my Dad's so the 2nd gas block dimple can be created then final assembly. with some favor from the weather god's I'll get out to the range on Sunday.
That’s what I would do. I used Loctite 620 for bedding the barrel. Don’t use the wheeler tool for lapping the receiver. Buy the brownells tool. I wouldn’t worry about the play between the upper and lower unless it’s excessive. I’ve only built a couple ARs. If you’re anywhere near Dayton, Ohio I’d be glad to help you do it since I have all the tools. If you buy a new barrel I’d get a bolt with it that is head spaced for that barrel. Also, get an adjustable gas block.
I have an M&P Sport II and would like to build a 0.5 MOA upper to shoot out to 600 yards. My lower has a JP SCS Gen II so I am hoping that comes in handy.
I would like to shoot mostly 55g factory ammo and see the same results that wilsoncs3980 saw.
Any recommendations? Thanks.
Built two AR platforms for precision shooting both are under .5 moa.
Build one: AR-10 .260
Mega upper lower set, geissele nm trigger, magpul prs, ergo grip, jp 22” barrel with their XL gas system, jp adjustable gas block, jp full mass bcg, jp silent capture, jp handguard, tbac ultra 7 and a USO 5-25 in a spuhr mount. Shooting Lapua brass, 210M primers, H4831SC, and Berger 130gr hybrid AR.
Build two: AR-15 .223 wylde
Seekins upper and lower set, geissele nm trigger, magpul prs, ergo grip, jp 20 barrel, rifle length gas system, jp detent adjustable gas block, jp v mass bcg, jp silent capture, jp handgaurd, tbac ultra 7, and a NF ATACR 4-16 in a spuhr. Still doing load development on this one using 77gr tmk’s But so far I’ve consistently got .45”-.6” groups, it is also in the .5-.75 Shooting Prime factory ammo, which is a good source for brass
. This build might also get a 224 valk upper for it depending on how the valk takes off.
Build one: AR-10 .260
Mega upper lower set, geissele nm trigger, magpul prs, ergo grip, jp 22” barrel with their XL gas system, jp adjustable gas block, jp full mass bcg, jp silent capture, jp handguard, tbac ultra 7 and a USO 5-25 in a spuhr mount. Shooting Lapua brass, 210M primers, H4831SC, and Berger 130gr hybrid AR.
Build two: AR-15 .223 wylde
Seekins upper and lower set, geissele nm trigger, magpul prs, ergo grip, jp 20 barrel, rifle length gas system, jp detent adjustable gas block, jp v mass bcg, jp silent capture, jp handgaurd, tbac ultra 7, and a NF ATACR 4-16 in a spuhr. Still doing load development on this one using 77gr tmk’s But so far I’ve consistently got .45”-.6” groups, it is also in the .5-.75 Shooting Prime factory ammo, which is a good source for brass
. This build might also get a 224 valk upper for it depending on how the valk takes off.Attachments
I feel I should respond to the LaRue comment above, that they will come up short, and some of the fan boys wi be unhappy.
I have a LaRue OBR in 7.62, one of the earlier ones with a Walter-Lothar barrel. It’s a tack driver, and a 1/4-1/2 MOA rifle all day with FGGM ammo.
I live in Marylandistan, the communist republic, potentially Soviet Republic, and didn’t want to deal with picking up another lower.
LaRue is making 65CM uppers with +2 gas systems, and it was a pretty cool idea to just slap on another upper on my lower, and work up a decent load for some distance shooting.
Unfortunately, while the original 7.62 upper was very well mated to the lower, the LaRue Ultimate Upper 65CM did not lockup well on the lower. In fact, there is so much slop in the lower, you can actually see daylight between the upper and lower with an Accuwedge installed.
This does not happen with the original 762 upper.
When I called LaRue yesterday, I got a bit of double talk and talk around. A lot of “this is what you can see with MilSpec,” and how different receivers fit together. I responded by saying: does LaRue make to milspec or used old CNC bits? I thought they made precision equipment... I can see how if it was not going on a LaRue lower, it would be a different story. LaRue told me to use an Accuwedge...
Anyway, what I’m seeing with the Ultimate Upper on a LaRue lower:
- Taken down pin has about .75-1mm of travel (you can see daylight)
- Pivot pin has good lockup compared to take down pin, but still has about 1/4mm of travel; allows side to side movement
- Pins are proprietary, so you can not use slightly larger pins from JP or others
I did take calipers to everything, and the 7.62 upper was a little tighter.
Honestly, for the money, I think there are better options. I’ve no idea if they make their 556 rifles differently. I’d probably consider a JP before I bought the LaRue IF you are looking for a 1/4 MOA rifle.
LaRue does make a VERY good rifle. That’s not in question.
I won’t lie to you, I can shoot that 65CM upper with the take down pin shimmed under 1/2 MOA. However, it would be a 1/4 MOA rifle all day without the slop... for that kind of cash, we shouldn’t be shimming or using an Accuwedge.
I have a LaRue OBR in 7.62, one of the earlier ones with a Walter-Lothar barrel. It’s a tack driver, and a 1/4-1/2 MOA rifle all day with FGGM ammo.
I live in Marylandistan, the communist republic, potentially Soviet Republic, and didn’t want to deal with picking up another lower.
LaRue is making 65CM uppers with +2 gas systems, and it was a pretty cool idea to just slap on another upper on my lower, and work up a decent load for some distance shooting.
Unfortunately, while the original 7.62 upper was very well mated to the lower, the LaRue Ultimate Upper 65CM did not lockup well on the lower. In fact, there is so much slop in the lower, you can actually see daylight between the upper and lower with an Accuwedge installed.
This does not happen with the original 762 upper.
When I called LaRue yesterday, I got a bit of double talk and talk around. A lot of “this is what you can see with MilSpec,” and how different receivers fit together. I responded by saying: does LaRue make to milspec or used old CNC bits? I thought they made precision equipment... I can see how if it was not going on a LaRue lower, it would be a different story. LaRue told me to use an Accuwedge...
Anyway, what I’m seeing with the Ultimate Upper on a LaRue lower:
- Taken down pin has about .75-1mm of travel (you can see daylight)
- Pivot pin has good lockup compared to take down pin, but still has about 1/4mm of travel; allows side to side movement
- Pins are proprietary, so you can not use slightly larger pins from JP or others
I did take calipers to everything, and the 7.62 upper was a little tighter.
Honestly, for the money, I think there are better options. I’ve no idea if they make their 556 rifles differently. I’d probably consider a JP before I bought the LaRue IF you are looking for a 1/4 MOA rifle.
LaRue does make a VERY good rifle. That’s not in question.
I won’t lie to you, I can shoot that 65CM upper with the take down pin shimmed under 1/2 MOA. However, it would be a 1/4 MOA rifle all day without the slop... for that kind of cash, we shouldn’t be shimming or using an Accuwedge.
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Can you give me a definition of 1/4 moa rifle? Do you mean one that has shot a 1/4 moa or a rifle that can day in and day out shoot 1/4 moa?
I doubt there are many rifles and shooters that can shoot 1/4 more day in and day out?
I doubt there are many rifles and shooters that can shoot 1/4 more day in and day out?
Where in MD are you? I'm in St. Mary's. I haven't kept up lately but last I checked, large frame ARs are cash and carry. It's only the small frame that are regulated.
I'm anal attentive about tight uppers and lowers too, but if your lower is older, that may be why you're having issues. Larue could very well have changed the specs since you first bought yours.
1/4 MOA is a lot to ask for out of a semi.
A firearm that can put bullets in or touching the same hole when shot from a rest unde ideal atmospheric conditions.
I have about 5 rifle systems that, until the barrels loose accurate life, can do that.
I have about 5 rifle systems that, until the barrels loose accurate life, can do that.
Actually, yeah, I was thinking about that... the LaRue changing specs / design. I asked them that... didn’t get a no, but the dude wouldn’t say yes either. The lower has no signs of wear at all.... given that it’s got, according to the log book, ~780 rounds on it.
Again, they make a quality machined product... we’re talking tolerances here... and the fact that the lowers are made to use proprietary pins.
In MD a lower without an upper is treated as a restricted weapon. I’m pretty sure they will not let you buy one at this point. I could check, but I’m going to do the next build as a JP.
1/4 is aggressive, and I’m not some amazing gas gun user. I tend to love my bolt guns, and do very well with them.
Generally:
The concern here is that the weapon needs to be as accurate as possible, so that you, the shooter, can do your best.
I think folks can get a more cost effective solution and get that sub-1/2 MOA gas gun for far less than LaRue charges. ....or you can spend the cash with JP and get exactly that.
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Direct comparison between a LaRue Stealth upper (LW barrel) and a JP upper in 556/.223 Wylde chamber.....both on the same lower (LMT lower with Geissele trigger and Luth AR stock). The JP shoots circles around the LaRue. JP groups are half the size of the LaRue. Not even close.
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Since I originally responded to this thread, I sold off the Larue and the Ultimate Upper.
The fact is that Larue didn't bother to tell me that they had changed the pattern of their lowers, and, effectively, pulled some used car salesman type shit on me when they told me the Ultimate Upper would work without issue. (Clearly, not mating to the lower without requiring shimming in the form of an accuwedge is an "issue.")
I picked up an LMT MWS with the ability to quick change barrels, and have an 18in Bartlein and a 22in Proof CF, and they shoot circles around the Larue UU on an OBR 762 lower. (FGGM to 1/4 group at 100 yards from prone)
My issue with Larue remains that I told them what I was doing when I placed the order, and they told me there were no issues with what I intended to do.... but were happy to try to get me to purchase more crap from them to fix the problem (in the form of another whole lower).
In the real world that considered underhanded and deceptive advertising / lying.
The fact is that Larue didn't bother to tell me that they had changed the pattern of their lowers, and, effectively, pulled some used car salesman type shit on me when they told me the Ultimate Upper would work without issue. (Clearly, not mating to the lower without requiring shimming in the form of an accuwedge is an "issue.")
I picked up an LMT MWS with the ability to quick change barrels, and have an 18in Bartlein and a 22in Proof CF, and they shoot circles around the Larue UU on an OBR 762 lower. (FGGM to 1/4 group at 100 yards from prone)
My issue with Larue remains that I told them what I was doing when I placed the order, and they told me there were no issues with what I intended to do.... but were happy to try to get me to purchase more crap from them to fix the problem (in the form of another whole lower).
In the real world that considered underhanded and deceptive advertising / lying.
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