I am currently building a 16" small frame AR in 5.56 with a focus on making it as accurate as possible. Will any high quality BCG work for me or are them some that just work better. The highly accurate part of this build is what is new to me.
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Bolt Carrier Group impact on accuracy?
- Thread starter ut755ln
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Barrel, barrel fit, fit between the upper and lower, handguard fit/rigidity will all affect accuracy more than the BCG in my opinion, dont buy a cheap no name BCG but that isnt where you are going to see the biggest difference in accuracy.
The barrel is going to represent say around 90-95%. Everything else is the remainder.
The most important piece is the Barrel ( mine are Bartlein). Any quality BCG ( I use Jp full mass) will work.
I just don't know the answer to your question but agree with the above mentioned replies where the barrel is a huge part. That said, I've read the articles by Joe Carlos many times and stuff from others looking for "the secret".
A barrel from known accuracy companies fitted tight, good triggers, stiff forearm also from known accuracy companies (Seekins, Geissele, etc), a stiff upper, and IMO a good tight upper/lower fit. You also can add a scope that fits the yardage you plan to shoot. Since it appears you are building from the ground up, you may as well get a quality BCG.
The articles I mentioned by Joe Carlos suggested a JP FMOS, a Young Manufacturing NM (no longer available I suspect), and I believe the Lantac (I may be mistaken on the last). I have and use the JP's and Young Manufacturing NM carriers. Did they make any difference? I don't know as the rifles were built using them. I also built every rifle with accuracy in mind and have not been disappointed.
A barrel from known accuracy companies fitted tight, good triggers, stiff forearm also from known accuracy companies (Seekins, Geissele, etc), a stiff upper, and IMO a good tight upper/lower fit. You also can add a scope that fits the yardage you plan to shoot. Since it appears you are building from the ground up, you may as well get a quality BCG.
The articles I mentioned by Joe Carlos suggested a JP FMOS, a Young Manufacturing NM (no longer available I suspect), and I believe the Lantac (I may be mistaken on the last). I have and use the JP's and Young Manufacturing NM carriers. Did they make any difference? I don't know as the rifles were built using them. I also built every rifle with accuracy in mind and have not been disappointed.
What I have so far
Radian builder set with 14.5" handguard
Proof 16" SS barrel, intermediate gas length
Geissele SSA-E trigger
Hux Suppresor
LMT parts kit
Considering buffer and spring setups
Gasblocks (fixed vs superlative vs riflespeed)
BCG
Bipod (Harris vs Atlas, to pan or not to pan)
To Arca or not Arca
Optic looking at quite a few, 1x8 atacr, Vortex HD 1-10, Khales 1x8
I have always focused on reliability and ignored accuracy (just kind of inherent AR platform accuracy). I am trying to do both this time.
Proof headspaces with JP bolts fyi
If interested in the YMNM… https://www.specialpurposerifles.com/ar15-parts/young-national-match-m16-bolt-carrier-group
Bolt headspace contribution is lug length minus face depth and has a small tolerance range
(0.153" to 0.156") for the 5.56 bolt.
I doubt any high quality bolt will be at either extreme, likely in the middle, or real close to 0.1545".
But, since I don't have one of these high quality bolts to measure it's just a guess.
(0.153" to 0.156") for the 5.56 bolt.
I doubt any high quality bolt will be at either extreme, likely in the middle, or real close to 0.1545".
But, since I don't have one of these high quality bolts to measure it's just a guess.
I agree with you on requiring reliability. With very good parts assembled with care and a purpose you get both. I know you know that and I am not being sarcastic.
One of the higher quality carriers won't hurt your intention for your build with the exception of $$$. It's not a cheap hobby when you're buying good parts is it. I hate to think I've wasted money so I won't think on it....
I suppose I should state I am referring to the carrier more than a complete BCG.
Is that actually in stock? I understand KE Arms bought Young Manufacturing and I haven't seen a NM BCG in a year or more. I have seen that website before but never called them to double-check.
It all depends on what you want to do with the rifle and how you plan on using it.
The components on their own seem fine to me. The difference will be in the soup. If you had a bottle of the best ketchup money can buy, on its own it's great. On fries it will be even better. However if you put that ketchup on a medium rare waygu steak it's not going to be so good.
Your original post was about specifically the rifle and accuracy. Another HUGE component of doing that is reloading. I don't care how good the parts are, if you shoot bad ammo it won't be accurate. That's a whole other rabbit hole to go down another day.
For me, it seems like it's evolving into a review my parts/AR build, which is ok. That said in my opinion it's substantially more important to lay out a rifle specifically for a specific role and THEN make sure all of the components compliment each other and not just by appearance.
Practiscore
Some two gun, some precision gas gun matches. The precision gas gun matches is the hard part.
When I put my first precision ARtogether I picked pieces but also built my own roadmap. I went through each part of a string of shots. Each event affects a set of components. Some were fixed, for example I am not in a position to reload anymore, so I picked ammo with a proven track record. I am very picky about my trigger pull, so I picked a precision trigger ( trigger tech Diamond).
So what I am thinking is you need to build you glow of a shot (includes things like recoil, ejection, stripping a new round, ect. Evaluating each for what you expect will help you pick the right stuff and ask the right questions.
So what I am thinking is you need to build you glow of a shot (includes things like recoil, ejection, stripping a new round, ect. Evaluating each for what you expect will help you pick the right stuff and ask the right questions.
When I went down this hole years ago, I think it turned out to be maybe 1/10th MOA at best improvement if the stars aligned.
The theory is that a larger diameter bolt carrier rail OD should help align the bolt into the extension better and provide more consistent and concentric lock-up, with the cartridge more centered in the chamber.
The problem people were having with some of the oversized carriers was sluggish cyclic rate and return stroke into battery due to them dragging inside the carrier raceway. I remember the posts from people who we couldn’t figure out what was going on until we asked for a detailed break down of their critical components, and as soon as we saw the oversize carrier, bam.
1/10th MOA improvement is well within the error of ammunition. You could have a laser rifle that shoots bugholes but it will not shoot bugholes group-after-group from a gas gun even with the best ammo. It will be good, but not that good.
The carrier’s contribution to accuracy is not worth pursuing if it comes at a sacrifice in reliability.
Especially on a 16” AR, you’re wasting your time trying to wring out accuracy with the carrier.
It’s all about the barrel, bedding, trigger, and balanced torque on the muzzle device and optic fasteners/mounts.
16” guns can be squirrely to shoot, so be happy with consistent 3/4 - 1” performance at 100yds and go shoot them. I have one 16” Grendel that shoots shockingly-well since it has a lightweight Wasp profile Lilja barrel, but when you run a set of groupings with lighter ARs, you’ll be lucky to have an average of 1 MOA if you’re being honest with yourself and not cherry-picking groups. 1 MOA is more than adequate for most disciplines.
The theory is that a larger diameter bolt carrier rail OD should help align the bolt into the extension better and provide more consistent and concentric lock-up, with the cartridge more centered in the chamber.
The problem people were having with some of the oversized carriers was sluggish cyclic rate and return stroke into battery due to them dragging inside the carrier raceway. I remember the posts from people who we couldn’t figure out what was going on until we asked for a detailed break down of their critical components, and as soon as we saw the oversize carrier, bam.
1/10th MOA improvement is well within the error of ammunition. You could have a laser rifle that shoots bugholes but it will not shoot bugholes group-after-group from a gas gun even with the best ammo. It will be good, but not that good.
The carrier’s contribution to accuracy is not worth pursuing if it comes at a sacrifice in reliability.
Especially on a 16” AR, you’re wasting your time trying to wring out accuracy with the carrier.
It’s all about the barrel, bedding, trigger, and balanced torque on the muzzle device and optic fasteners/mounts.
16” guns can be squirrely to shoot, so be happy with consistent 3/4 - 1” performance at 100yds and go shoot them. I have one 16” Grendel that shoots shockingly-well since it has a lightweight Wasp profile Lilja barrel, but when you run a set of groupings with lighter ARs, you’ll be lucky to have an average of 1 MOA if you’re being honest with yourself and not cherry-picking groups. 1 MOA is more than adequate for most disciplines.
I would be ecstatic with 1 MOA and factory ammunition, honestly I would be ecstatic with 1 MOA and hand loads.
Just get a regular old phosphate milspec bcg. Not a fan of most coatings/nitride on bolts it weakens the little parts like the extractors imho. I think WCArmory has a shipment of microbest bcg right now.
A properly built gas gun with a good barrel & good hand loads can do sub moa all day long at 100 yards.
Is this currently in stock?
| Sat, Mar 9, 6:07 PM (14 hours ago) | |||
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It’s not. Our website provider has frozen our card processing ability because we sell guns.
We should have a new updated website in the coming weeks.
Thanks,
Rob
The owner of KE Arms bought Young Manufacturing, but they are separate entities. KE Arms sort of took over the Young website/cross-listed products and sold what inventory that remained in stock after the sale until the "new" Young Mfg finished relocating the production facility. After that, there are rumors of what's happening now as far as production, plus the KE lawsuit and a bunch of drama.
I didn't even realize there was a lawsuit until you mentioned it msgriff. I looked it up and had to scratch my knot in wonder. WTH!
Nevertheless, I wouldn't get rid of my JP FMOS carriers but I also wouldn't mind having more Young Manufacturing NM carriers.
Sorry for the derail OP!
Nevertheless, I wouldn't get rid of my JP FMOS carriers but I also wouldn't mind having more Young Manufacturing NM carriers.
Sorry for the derail OP!
The old Young National Match bolt carrier was literally fantastic - Forged, then centerless ground, then chrome plated. Not being inclined to stop there, I've been sending them to Ionbond for DLC coating since 2004:
Wish they still made them like that! Yes, that's a JP bolt in there, also now Ionbond DLC coated, saving me that step.
The Young N/M bolt carrier outside diameter is the largest I've encountered. They never would work in all uppers. The JP FMOS bolt carriers - currently the best available, I believe - is a close second in outside diameter:
Tighter tolerances can - to a certain degree - help accuracy. But, as previously well detailed, tighter tolerances can adversely affect reliability at some point.
Thread hijack follows:
I'm suffering from that now. I've built hundreds of very successful custom AR's on San Tan Tactical (STT) billet receiver sets over the last ten years. Good looking product, well designed, great tolerance control, and with anodizing so good other top shelf components next to STT looked cheap. Fantastic people were there, too.
Since CMC bought San Tan Tactical and moved them from Arizona to Texas (without the people), STT uppers are so tight inside that neither a Young N/M nor a JP FMOS will even begin to fit inside one. At least their new anodizing doesn't make other components look bad...
Now, I'm trying to figure out who will succeed San Tan Tactical as my billet receiver set of choice.
I really like Radian's quality, but I wish they were not so heavy. Perfect Cerakote work.
Rogue Ops is a contender, and lighter, but their forend length choices are quite limited. Maybe use their receivers and Geissele rails???
I think I know who it might be (cough - Blackout Tactical...), but I'm just not important enough to get them to sell to me.
Wish they still made them like that! Yes, that's a JP bolt in there, also now Ionbond DLC coated, saving me that step.
The Young N/M bolt carrier outside diameter is the largest I've encountered. They never would work in all uppers. The JP FMOS bolt carriers - currently the best available, I believe - is a close second in outside diameter:
Tighter tolerances can - to a certain degree - help accuracy. But, as previously well detailed, tighter tolerances can adversely affect reliability at some point.
Thread hijack follows:
I'm suffering from that now. I've built hundreds of very successful custom AR's on San Tan Tactical (STT) billet receiver sets over the last ten years. Good looking product, well designed, great tolerance control, and with anodizing so good other top shelf components next to STT looked cheap. Fantastic people were there, too.
Since CMC bought San Tan Tactical and moved them from Arizona to Texas (without the people), STT uppers are so tight inside that neither a Young N/M nor a JP FMOS will even begin to fit inside one. At least their new anodizing doesn't make other components look bad...
Now, I'm trying to figure out who will succeed San Tan Tactical as my billet receiver set of choice.
I really like Radian's quality, but I wish they were not so heavy. Perfect Cerakote work.
Rogue Ops is a contender, and lighter, but their forend length choices are quite limited. Maybe use their receivers and Geissele rails???
I think I know who it might be (cough - Blackout Tactical...), but I'm just not important enough to get them to sell to me.
A number of years ago I put together a 16" AR that turned out to be very accurate as far as I am concerned. I repeated the performance numerous times so it wasn't a fluke...on average for 10 shot groups I would be between .5 and .75 for all 10 shots with my handloads. It was very reliable using my ammo. Generally speaking that's the kind of performance I was getting until I started doing other stuff with other rifles.
It IS doable to have a great shooter. In my case I did not do ANY of that special stuff. Regular bolt carrier group...none of that fitting the barrel or whatever so just pretty generic stuff.
In either case it depends how deep you want to go down the rabbit hole and how much time you want to put into it. I am glad to see that your expectations are realistic. That's definitely doable to get a 1 MOA rifle but the wild card there will be the ammo and how much you are willing to spend on the good stuff.
Has there been any information on any of this since your Post? I bought a YM Aluminum Vented Float Tube Handguard for a 6.5 CM Build, on a DPMS Upper and Lower. I love that Handguard.
Recently, I went to their Website to purchase another one, and they were gone. Trying to call their Number was pointless. Three Rings, and the System simply hangs up. I also checked another Website that carried their Products, but only found the Barrel Nut and Lock Ring, no Tube. Further searching led me here, where I saw the above information on the buy out.
Trying to call or email KE Arms is fruitless. Same thing, three rings and the System hangs up, and there are zero replies to Emails. Have they also decided to fold? I did notice KE's Site was recently updated, regarding an Out of Office Notification, for a Match a couple of weeks ago, which is gone now, but they still do not answer Emails or Phone Calls.
I live in Arizona, and could probably drive the 3 hours or so to do a Welfare Check, but at this point, I've finished the other Upper Build with another Manufacturers Handguard. I do have several YM Tools, which are awesome.
Are either of these Companies going to be back in Business and ACTIVELY engaging with Customers again? Anyone have comms with them? Thanks in advance.
I would contact a guy named Russell Phagan, one of the executives at KE Arms. He goes by the name of Sinistral Rifleman on various websites/forums/platforms. He's pals with Karl Kasarda of InRange TV, and posts a lot on that Reddit sub.
Wow. I did find his Reddit Post (through a Search) regarding the Lawsuit. Perhaps hes just temporarily down until this gets resolved one way or the other.
Still wondering what the deal with Young Manufacturing is though. It's not clear whether they sold to KE, or temporarily just sold Stock through KE until they moved, retooled, or closed (due to sale?). Perhaps someone will answer a phone or email soon. I've been trying for three weeks now.
Thanks again.
Take a look at Cross Machine Tool.
I really liked the SanTan stuff, good to know the info you posted too as I haven't used any of their stuff for the last 3 years, mainly because of availability.
MM
The JP LMOS in my small frame from them is amazing. I can't comment one way or the other on how it does or doesn't contribute to accuracy, but the LMOS with their SCS sure makes a smooth shooting system. I'm sure this translates to accuracy downrange.
