First AR-10.. DD or Seekins?

Glock1943

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I am thinking about getting into long range shooting so I'd like to get an AR-10 chambered in .308. I'm former military police and have experience with the AR-15/M4 platform but not the AR-10. I'm looking at either a SP10 or a DD. Any thoughts or advice would be much appreciated.
 
SP10 would have my vote. I’ve seen a lot of great performance out of them.

I can’t say I’ve seen the same for the large frame DDs. I’ve seen several students over the last few years that have had issues with large frame DD rifles having POI shifts when shooting off of tripods/barriers vs prone. Often to the magnitude of 4 MOA. 😬
 
I think you will be ok with either of them. I understand the concept of the receiver extension but I don't think many of us are at a point where we can definitively isolate receiver load as a cause of POI shift. People over estimate their positional shooting abilities especially with gassers.
 
No, definitely able to isolate the issues with the Daniel Defense rifles. “Student” does not mean incapable.

One particular example was a professional shooter who was running a V3. Her performance was well noted by myself and other instructors present from earlier courses she attended.

She shot well through the entire morning of this particular course, then in the afternoon during the tripod course of fire her POI dropped dramatically down 4 MOA from her 100y zero. Her groups maintained roughly 1-1.5 MOA.

Upon investigation by two instructors the phenomenon was repeated, the rifle zero from the prone off the bipods then moved immediately to the tripod and exhibiting a 4 MOA shift down in POI.

This is not the first (or the last) large frame Daniel Defense rifle I have seen do this and quite frankly it’s not necessarily a problem that’s unique only to them. But the SP10 has not exhibited such things out of the handful I’ve seen. I think the SP10 might be one of the best kept secrets in large frame has guns.
 
The Seekins .308 builders kit took a year to get. Kept putting me off every 3-6 months. I was told all the parts go to fully built rifles first. That just angered me. Then why sell a “builders kit” if you don’t want to supply it. Or at least be up front about that. Ultimately at 1 year I was fed up and they made it right. I didn’t even need a BCG or barrel! I have a several of their guns and they perform well and have very nice fit and finish.
 
I'm at the beginning of research so any corrections and advice would be welcome for a .308:
Barrel twist: 1:10
Length: 24"
Barrel: CMV or stainless?
Trigger?
BCG?

What else should I look for in an AR-10?
 
I'm at the beginning of research so any corrections and advice would be welcome for a .308:
Barrel twist: 1:10
Length: 24"
Barrel: CMV or stainless?
Trigger?
BCG?

What else should I look for in an AR-10?

24" is a over kill for .308, I'd recommend 18-20" Stainless, and 1-10 twist is perfect.

For trigger I'm a huge fan of TriggerTech, but if on a Budget get a LaRue MBT.

For BCG JP is going to be top tier, but I've had good results with RCA and Lantac.
 
Last I checked McBrides guns, in Austin TX had a 308 SP10 for sale. I tracked it down for a friend who ended up passing on it. I know they're hard to find right now. Think it was priced at $2.2k.

I love my Seekins DMR build, probably would have bought a SP10 had a cheap MWS not fallen into my lap.
 
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24" barrel would be a heavy sonofabit__. Large Frame Ar's get heavy fast.

Just as an FYI, and to give some kind of idea... read this link.
https://rifleshooter.com/2014/12/30...ato-barrel-length-versus-velocity-28-to-16-5/

Lots of great triggers available.... I use Geissele SSA-E's a lot. Your choice can be a personal thing. ( No Kidding )

Quality , well respected BCG manufacturer is preferred by me, lots of gtg middle of the road choices, ( Lantac, CMC triggers Suppresor ready ) and high end choices. Do not buy a cheap BCG.

Barrel wise ( for that matter what is your budget ? ) Buy the best barrel you can afford. ( It is a bargain considering the price of ammo. )
 
I’ve had LMT and don’t consider them a step up by any means. Seekins SP10(M) is every bit the rifle LMT is with excellent customer service.

The only difference between the M series and standard SP10 is the way the barrel is fitted to the upper receiver, and you can pick whatever barrel profile/Gas you prefer.
 
If you can afford it, JP

It’s just easier to get a one and done off the bat.

It’s like PSA or no name gun show shit

Mid tier KAC, DD, S&W, Sig etc

And JP and a few very well thought out custom builds.
 
If you’re not aware and considering a Proof CF barrel, they are headspaced for JP bolts. Use whatever carrier you want. I used Fail Zero and have been happy with it. I also used a Superlative Arms agb but others like SLR which are solid. I used a Tubbs AR10 spring and KAK 5.3oz AR10 (2.5”) buffer.
I’m listing this because, unless you buy a complete rifle, if you start piecing together large frame ARs there’s a lot of posts of folk’s guns not running properly.
This particular set up runs great. Suppressed and unsupressed.
 
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I'll be "that guy". If you're just getting into long range shooting I wouldn't advise a large frame in 308. Or a large frame AR at all.
I mean, you’re not wrong …but then again this is the territory of those who always seem to think that they are the exception to the rule. 🙄😂
 
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I mean, you’re not wrong …but then again this is the territory of those who always seem to think that they are the exception to the rule. 🙄😂
I've seen this written myriad times, and I have no reason to believe that it is not true. But, below is the first 5 shot group I ever fired from a semi auto rifle that was not a 10/22. While the rifle hasn't had a scope mounted in a few years, it always put down similar groups with Hornady Match and FGMM 168. That 0.843" is an edge to edge measurement.

The above notwithstanding, I will echo that a small frame gun is easier to shoot...

IMG_4486.JPG
 
Could you describe what you mean by long range? If you’re shooting 600yd or less, a .308 gas gun is a fun platform with endless good ammo choices. I have one that shoots well but I prefer my bolt guns more, they’re quieter because the action isn’t cycling, more accurate, naturally incorporate better triggers than AR’s can, and you don’t have to go through the tuning woes that gas guns can sometimes bring.

With that said if I was doing a gas gun I would just build one. It’ll be cheaper and have as good or better parts than almost any factory gun. Even large frame gas guns are so easy to piece together now it isn’t a big deal to do so and have it work great.

If you want to shoot 800yd+ you might like a more ballistically capable cartridge like 6.5 creedmoor. You can do a lot with .308, the creedmoor is just easier (but a little more finicky in a gas gun).
 
I am thinking about getting into long range shooting so I'd like to get an AR-10 chambered in .308. I'm former military police and have experience with the AR-15/M4 platform but not the AR-10. I'm looking at either a SP10 or a DD. Any thoughts or advice would be much appreciated.
I had a DD5 V5 (20" in 6.5 CM). Never had a single problem with it. I shot sub 1 MOA with factory ammo. Daniel Defense makes quality stuff as does JP, Seekins, and others. Some DD stuff I noticed, they make their own barrels and hammer forged and chromed lined with sub 1 MOA is pretty sweet. Their bolt is a little different as well, two extractors and a buffer weight in the BCG in addition to the normal buffer.
 
The problem with the DD V5 is the Barrel/Handguard interface, as shown below the barrel extension utilizes a flange system so the Handguard and Barrel are secured directly to the upper with a 4 bolt design.

DD5-Carbon-Breech__35636.1644951079.1280.1280__39656.1644951506.png
DD5V1-11.jpg


The benefits are it doesn't require special tools for barrel/barrel nut removal, but due to the design any pressure/torque applied to the handguard will directly transfer to the barrel causing as stated above a POI shift.

My advice... Pull the barrel and bed the barrel extension with Loctite 620 and make sure all 4 bolts are torqued down exactly the same so that torque distribution isn't uneven.
 
I've seen this written myriad times, and I have no reason to believe that it is not true. But, below is the first 5 shot group I ever fired from a semi auto rifle that was not a 10/22. While the rifle hasn't had a scope mounted in a few years, it always put down similar groups with Hornady Match and FGMM 168. That 0.843" is an edge to edge measurement.

The above notwithstanding, I will echo that a small frame gun is easier to shoot...

View attachment 7862402
Perfect example here. I can lay down 6 shots 0.65” but then 4 more are scattered. I doubt it’s the gun because I’ve kept all 10 at about an inch. My bolt .308 is 0.8” all day. That’s probably me too.
9D7C5FE5-BBDC-4963-B882-1E89DD814195.jpeg
1608F6C7-F1D8-466E-8955-1DAC8C299805.jpeg
 
The benefits are it doesn't require special tools for barrel/barrel nut removal, but due to the design any pressure/torque applied to the handguard will directly transfer to the barrel causing as stated above a POI shift.
I currently only have my MK18, I have put pressure on the rails on barricades and things like that but never noticed any shift. On the DD5, I guess the pressure from a charged bipod wasn't enough for me to pick up a difference.
 
My vote goes to Seekins. They shoot extremely well and they have always made things right for me. I’m actually getting ready to order one of their DMR rifles in 223. I just can’t decide on barrel length.
 
I have a DD5V1. Bought when they first came out. It’s Shoots ok, 1-1.5 MOA groups with good ammo. In hindsight I wished I would have spent the $3k on another bolt rifle. Take that for what it’s worth.
 
My beginning LR rifle was a Ruger Precision Rifle (RPR) in .308. A very good starting rifle. Bolt action and loved the Hornady 168gr Match. $1300+/- plus a scope and a bipod. I could hit 7-800 yards but 1000 got iffy. Ive done it but if 1000+ is what you'd like to do get a 6.5 Creedmoor.

My preference for LR is a bolt gun over an AR. Much more stable to create good second shots.

But what the hell, I've got lots of both styles! Always seem to be one shot of a full inventory!
 
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AR-10's order of arms is the same as an AR-15, but they "build" differently in some ways if you ever build your own. DD for a factory gun is hard to beat. If truly going for distance consider the 6.5cm or 6.5prc.. Check out the ballistic tables of each before buying.
 
I'm late to the party here, but I've owned them both and there's simply no comparison...ok maybe in accuracy capability, but that's where the similarity ends. The Seekins is so much smoother and softer recoiling, the springs and bolt noise - it's quieter, the trigger is better, and customer service is more personal. It's crazy just how much better the Seekins feels to shoot.
 
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I am thinking about getting into long range shooting so I'd like to get an AR-10 chambered in .308. I'm former military police and have experience with the AR-15/M4 platform but not the AR-10. I'm looking at either a SP10 or a DD. Any thoughts or advice would be much appreciated.
Long range shooting is a lot of fun, you are going to love it. It's also highly addictive, so be careful :) . I recently got into long range myself, and have been running a .308 gas gun in PRS matches for almost a year now. I have been building and loading for gas guns for many years, and love the platform. That being said, I am currently in the process of building my first custom bolt gun around the 6GT cartridge. I don't want to dissuade you from your gas gun build, but if long range shooting starts to consume you (highly likely), you are probably going to want to graduate to a bolt gun at some point. I would definitely advise going the custom route for your gas gun. The platform can be finnicky, and it might prove useful for you to choose and assemble the components yourself to better allow you to diagnose and address any issues that may come up. Below are some specs on my .308 which runs smooth with no issues. I load Lapua brass with 41.5gr IMR 4064 and 175gr SMK:

PWS Lower/Upper receiver set
CMMG Lower parts kit
Geiselle Hi Speed NM Trigger
CMMG 24" HT Barrel Salt Bath Nitride 1:10
Odin Works Adjustable Gas Block .936''
JP Compensator Muzzle brake
JP High Pressure Enhanced Bolt
JP Stainless LMOS
JP Gen 2 Silent Captured Spring
Magpul PRS Gen3 Stock
 
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I'm at the beginning of research so any corrections and advice would be welcome for a .308:
Barrel twist: 1:10
Length: 24"
Barrel: CMV or stainless?
Trigger?
BCG?

What else should I look for in an AR-10?

Get a bolt gun 308 with a 22-24" heavy barrel and a chassis that is adjustable. It will be easier to shoot for "learning long range" and most ranges are single fed for the f class/br/service rifle days which is when you'll be shooting to get experience. You'll have more leeway with handloads too I think with my tikka I was using a 185 berger with 47.5 2000MR 2.85" long which would never fit in a AR10 pmag lol.
 
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The only issue you might encounter is actually finding a Seekins. I've had mine on order since April 2021. I wasn't in a huge rush, so the expected 8 month wait didn't bother me. What does bug me is how 8 months became 9, then 10, then 12, then 13 without any communication. Yes, when I send an email, they respond within a few days
 
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The Seekins .308 builders kit took a year to get. Kept putting me off every 3-6 months. I was told all the parts go to fully built rifles first. That just angered me. Then why sell a “builders kit” if you don’t want to supply it. Or at least be up front about that. Ultimately at 1 year I was fed up and they made it right. I didn’t even need a BCG or barrel! I have a several of their guns and they perform well and have very nice fit and finish.
Did you have the builders kit backordered? Or were you just waiting for it to be instock?

I've been waiting the last year for it to come in stock, which it did last week... so I ordered... but Seekins never shipped it. When I e-mailed to inquire, I was told, "oh sorry, our website isn't accurate, all those parts went to other orders and you are back ordered". I definitely feel bait and switched...

I was really annoyed that they never bothered to email me or anything... if I hadn't called I wouldn't have known... they told me 90 days if I haven't seen it ship to call them... but your post is making me nervous I'm in for a long wait.
 
Did you have the builders kit backordered? Or were you just waiting for it to be instock?

I've been waiting the last year for it to come in stock, which it did last week... so I ordered... but Seekins never shipped it. When I e-mailed to inquire, I was told, "oh sorry, our website isn't accurate, all those parts went to other orders and you are back ordered". I definitely feel bait and switched...

I was really annoyed that they never bothered to email me or anything... if I hadn't called I wouldn't have known... they told me 90 days if I haven't seen it ship to call them... but your post is making me nervous I'm in for a long wait.
It was back ordered when I ordered. I spoke to them at that time and they estimated 90 days. I understood that was an estimate, Covid, supply chain issues, etc. I was patient for 6 months and then called. I was told the same thing about the parts going to full builds. I was told 2-3 months more so I waited. At that point I asked to speak to someone higher up in management. I expressed feeling like the red headed step child and my feelings on selling something they didn’t have any intention of shipping. I was then told BCGs are the part they can’t make enough of. (Someone else on here said they were told the same thing).
I explained I was not waiting on a BCG or barrel.
I was told they were going to include some good swag to make up for the wait time…that was now almost a year. I raised a little hell and explained that I don’t need free advertisement for a company that is operating like this. I explained my past loyalty with several other builds but this was disappointing. The kit was shipped in a week.
 
seems like the Seekins SP10 rail-attachment system is similar to the Aero M5E1 enhanced? barrel nut threads into upper receiver, handguard attaches to a boss or snout forged as a part of the front-end of the upper receiver. loads imposed on the rail don't get transmitted onto the barrel nut, which is how traditional rails attach?