Upper and Lower Suggestions

_Windrider_

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  • Jun 26, 2012
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    Orlando, FL
    My next project is a 260 Gas Gun. I had planned on building it using the Seekins build kit found here, http://www.seekinsprecision.com/product/ar-lowers/sp10-build-kit-mlok.html

    However, i dont want to pigeonhole myself with looking into some other options. Who has suggestions for large frame Uppers and lowers? i could just buy a complete SP-10 i suppose, but i like building my guns and using the parts I want.
     
    I looked at building my own 6.5CM AR recently. I wanted to spec all of my parts out but it wasn’t worth it cost wise. I also talked to a lot of folks and found out AR10s can be funny when you want precision. I couldn’t afford to spend money and the more y getting it to shoot perfect. I decided to go with a proven product like the Seekins SP-10 like you mentioned above. I also liked the Seekins Upper as a whole. The receiver, the handguard, and how they mount is the best I’ve seen. It was the best bang for the buck.
     
    MEGA billet set is top notch and well known. Its what I use with a JP 17.5" Handguard with their ARCA rail.

    I would go with 6.5cm due to mag length limitations that do not plague 6.5cm...yes, there are certain bullets that work in 260 AR's but go 6.5cm if you want to shoot various bullets without jamming them down in the case.
     
    MEGA billet set is top notch and well known. Its what I use with a JP 17.5" Handguard with their ARCA rail.

    I would go with 6.5cm due to mag length limitations that do not plague 6.5cm...yes, there are certain bullets that work in 260 AR's but go 6.5cm if you want to shoot various bullets without jamming them down in the case.
    Can’t find mega anymore. ZEV killed it.
     
    I finished a 6.5 CM on an Aero upper and lower. I bought the set for $199. Lower has a tensioner screw to remove the play between upper and lower.
     

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    I like the Aero Precision M5E1 enhanced upper for the way the handguard is attached. Have put together for resale several of these using Aero Precision/Ballistic Advantage 22" 6.5 CM bbls. For a very reasonable charge, you can get the upper/lower/handguard CeraKoted in Magpul FDE. Also, they announce builder sets done in custom CK or HydraDip patterns every month.

    These are the last three I've finished, from top down: 24" Krieger; 22" Krieger; 22" Ballistic Advantage. Top two have 15" enhanced M-lok handguards, bottom one is a 12" M-lok.
     

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    I decided not to build a large frame and went with KAC. I do build small frames, done tons of those. There is a difference in receivers, I used to think there wasn't. I'd imagine the quality would be similar, so here's what I found to be best. Noveske is probably the best overall. Even their off label stuff is great. People think they're overpriced, and sure, you can get a good rifle for less, but their parts are damn near peerless and the one Noveske factory rifle I own is damn nice, perfect. LMT is good. I use KAC mostly now that they sell 'em but they don't do big frames and probably won't. Haven't used JP receivers, heard nothing but good, but I only use their BCG's --hands down one of the best parts for reliability, they work dry.

    IF Noveske sells N6 receivers, I'd go that way. Hell, if they do I may build one after all.
     
    I've used Aero Precision extensively over the years but moved away from them the last year. I had 3 situations with parts that were not milled properly. One was a M5 308 lower they forgot to mill the magazine release area and mags would just fa out the gun from day one. Customer service lost my lower for 3 months and after 100 calls and emails finally got a new lower. Their CS is horrible. One of their handguards laid on the gas tube which they confirmed after receiving it back and I took a refund that time.

    I'll never buy them again. Too many other great brands out there to choose from.
     
    I've used Aero Precision extensively over the years but moved away from them the last year. I had 3 situations with parts that were not milled properly. One was a M5 308 lower they forgot to mill the magazine release area and mags would just fa out the gun from day one. Customer service lost my lower for 3 months and after 100 calls and emails finally got a new lower. Their CS is horrible. One of their handguards laid on the gas tube which they confirmed after receiving it back and I took a refund that time.

    I'll never buy them again. Too many other great brands out there to choose from.
    Wow. That’s pretty bad. What’s the alternative you’ve found?
     
    If you're looking at billet, I'll throw SLR Rifleworks in there. I just built a 308 off one of their sets, extremely impressed. The fit between upper and lower is perfect. Very pleased with with the receivers.

     
    I like the Aero Precision M5E1 enhanced upper for the way the handguard is attached. Have put together for resale several of these using Aero Precision/Ballistic Advantage 22" 6.5 CM bbls. For a very reasonable charge, you can get the upper/lower/handguard CeraKoted in Magpul FDE. Also, they announce builder sets done in custom CK or HydraDip patterns every month.

    These are the last three I've finished, from top down: 24" Krieger; 22" Krieger; 22" Ballistic Advantage. Top two have 15" enhanced M-lok handguards, bottom one is a 12" M-lok.

    @flatland1, how do the Ballistic Advantage barrels shoot? I'm about to finish my creedmoor build with the 22". Couldn't find much info about them.
     
    I decided not to build a large frame and went with KAC. I do build small frames, done tons of those. There is a difference in receivers, I used to think there wasn't. I'd imagine the quality would be similar, so here's what I found to be best. Noveske is probably the best overall. Even their off label stuff is great. People think they're overpriced, and sure, you can get a good rifle for less, but their parts are damn near peerless and the one Noveske factory rifle I own is damn nice, perfect. LMT is good. I use KAC mostly now that they sell 'em but they don't do big frames and probably won't. Haven't used JP receivers, heard nothing but good, but I only use their BCG's --hands down one of the best parts for reliability, they work dry.

    IF Noveske sells N6 receivers, I'd go that way. Hell, if they do I may build one after all.

    +1 for LMT and I probably sound like a broken record on this, but KAC buys their lowers from LMT who manufacture them on a variance for KAC. If you buy KAC your buying LMT with the KAC logo.
     
    +1 for LMT and I probably sound like a broken record on this, but KAC buys their lowers from LMT who manufacture them on a variance for KAC. If you buy KAC your buying LMT with the KAC logo.
    Problem with LMt is you have to use their Handguard and all of them are super short. I like 15” minimum (no homo)
     
    @flatland1, how do the Ballistic Advantage barrels shoot? I'm about to finish my creedmoor build with the 22". Couldn't find much info about them.

    I haven't spent any time behind one of the BA 6.5CM bbls myself, so all the info I have is 2nd hand from customers. So far, I've not had any complaints on the accuracy, and the two guys who've bothered to let me know how theirs' shot were satisfied.
     
    I’d definitely go with the Seekins set you were looking at. IMO they give up nothing to anyone except maybe JP with their side chargers. Seekins is a higher quality product than Aero and not much more money, IMO Mega too since Zev took over... they ain’t what they used to be. Plus the SP3R forend is money for riding a bag.

    Add a JP BCG, JP SCS, Seekins parts kit, Geissele trigger of your liking, Superlative gas block, and a top quality barrel and you’re in business.

    Personally I’d go 6.5 creed in a gas gun over 260. It makes a little better use of the magazine OAL restrictions that come with the platform. You also have the advantage of lots of factory ammo offerings if you ever decide you don’t feel like loading to feed it.
     
    I’d definitely go with the Seekins set you were looking at. IMO they give up nothing to anyone except maybe JP with their side chargers. Seekins is a higher quality product than Aero and not much more money, IMO Mega too since Zev took over... they ain’t what they used to be. Plus the SP3R forend is money for riding a bag.

    Add a JP BCG, JP SCS, Seekins parts kit, Geissele trigger of your liking, Superlative gas block, and a top quality barrel and you’re in business.

    Personally I’d go 6.5 creed in a gas gun over 260. It makes a little better use of the magazine OAL restrictions that come with the platform. You also have the advantage of lots of factory ammo offerings if you ever decide you don’t feel like loading to feed it.
    Yeah I have. 6.5 creed gasser already. Just looking to do something different.
     
    I have 5 of the new MEGA/ZEV sets. They are equal if not better than the older MEGA sets. Some of the tightest upper/lower fitment of any billet sets I've tested. So tight, when I received my first set I had to call them because I thought they were out of spec and woukdnt go together. You had to align them perfectly and they are then a press fit. LOVE THEM

    I really like the Seekins set too but until they come out with a handguard longer than 15" I just wont buy them for +2 gas builds. Dont like the gas block exposed but that's just me
     
    I have 5 of the new MEGA/ZEV sets. They are equal if not better than the older MEGA sets. Some of the tightest upper/lower fitment of any billet sets I've tested. So tight, when I received my first set I had to call them because I thought they were out of spec and woukdnt go together. You had to align them perfectly and they are then a press fit. LOVE THEM

    I really like the Seekins set too but until they come out with a handguard longer than 15" I just wont buy them for +2 gas builds. Dont like the gas block exposed but that's just me
    They have a regular uper that you can use any Handguard. The only reason the block is exposed on the SP3R is because of the lever for the gas adjustment. They also have a low profile block that goes under any Handguard that u use an Allen key to adjust. The only thing I dont like about the ZEV’s (this is a perception) is they seem to busy. I feel like the cuts and milking just seem overkill. But I’ve never seen one, I’m purely going off images and fully admit I could be way off. I’m Ute I’ll use onev eentually
     
    The whole idea if using a Seekins bullet IMR3T
    They have a regular uper that you can use any Handguard. The only reason the block is exposed on the SP3R is because of the lever for the gas adjustment. They also have a low profile block that goes under any Handguard that u use an Allen key to adjust. The only thing I dont like about the ZEV’s (this is a perception) is they seem to busy. I feel like the cuts and milking just seem overkill. But I’ve never seen one, I’m purely going off images and fully admit I could be way off. I’m Ute I’ll use onev eentually


    The whole point of using a Seekins builders set is it comes with their iRMT receiver which is beefed up to handle heavier barrels and reduces stress/flexing. See Gabe's video at Seekins explaining this. If your not gonig to use their iRMT receive than I would be using other brands... The problem, as I explained above, is you can ONLY use their SP3R handguard which is 15" max leaving your ENTIRE gas block exposed on +2 gas systems. Not sure what you are talking about only reason block is exposed is because lever for gas adjustment?? No, the reason a gas block is exposed on a +2 gas system is because the gas system is longer than the 15" handguard. Thats why several companies including JP and Odin Works to name a few have come out with 17.5" handguards.

    This may not be an issue for some, but guys running PRS, hunting, etc dont like the block exposed due to the risk of smacking it on something, knocking it out of alignment and then the gun doesnt operate. If your shooting from a bench it doesnt really matter.

    Seekins has stated they are looking at making a longer SP3R handguard but nothing to purchase yet.


    Here's my MEGA/22" 6.5cm Rock Creek Cut Rifled +2 Gas / SLR 16" Solo Ultralite and you can see how the entire AGB is exposed





    Here's my MEGA/22" 6.5cm Rainier Ultramatch +2 Gas / JP MKIII Rapid Configuration 17.25" Handguard that covers the entire gas block




     
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    The whole idea if using a Seekins bullet IMR3T



    The whole point of using a Seekins builders set is it comes with their iRMT receiver which is beefed up to handle heavier barrels and reduces stress/flexing. See Gabe's video at Seekins explaining this. If your not gonig to use their iRMT receive than I would be using other brands... The problem, as I explained above, is you can ONLY use their SP3R handguard which is 15" max leaving your ENTIRE gas block exposed on +2 gas systems. Not sure what you are talking about only reason block is exposed is because lever for gas adjustment?? No, the reason a gas block is exposed on a +2 gas system is because the gas system is longer than the 15" handguard. Thats why several companies including JP and Odin Works to name a few have come out with 17.5" handguards.

    This may not be an issue for some, but guys running PRS, hunting, etc dont like the block exposed due to the risk of smacking it on something, knocking it out of alignment and then the gun doesnt operate. If your shooting from a bench it doesnt really matter.

    Seekins has stated they are looking at making a longer SP3R handguard but nothing to purchase yet.

    Ive asked the, for a custom 18” version of the SP3R. They are too busy just trying to manage current production.

    This is the gas block the SP-10 uses and why it’s a 15” Handguard, at least that’s what I was told.

    https://www.seekinsprecision.com/product/upper-accessories/select-adjustable-gas-block-876.html

    You couldn’t use this gas block with a longer guard. You would have to use this one

    https://www.seekinsprecision.com/pr...low-profile-adjustable-gas-block-750-dia.html

    EDIT: seriously considering using JP 18” guard with a ZEV or SLR Upper. But I did score a seekins code so I will likely just continue down that road. Total first world problems with all these choices.
     
    Your missing the point. The handguard and gas block has nothing to do with the 15" length issue. The major barrel players are using +2 gas systems on .260 and 6.5cm AR barrels these days. That puts the gas block out past the 15" handguard length exposed. The JP handguard is one of the nicest, most secure Large frame AR handguards Ive used. I just ordered 2 more.