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Discussion Starter · #1 ·
As some of you know a while back I decided to build an AR to best the SCAR. It was my thought that with all the existing upgrades available for the AR I might be able to match the advantages the SCAR has while retaining the huge advantages the AR has in parts availability and price for SHTF scenarios. The following features of the SCAR would have to be matched for me to be satisfied.

1) Free float barrel for accuracy I have heard the SCAR will do 1 moa so the AR must do at least that preferably better
2) Extended rail for mounting optics and accessories.
3) Side and bottom rails for lights and bipod.
4) Gas piston for reliability and ease of maintenance.
5) Adjustable comb for proper repeatable cheek weld.

I figured that I could probably gain some ground on the SCAR with a better trigger and more accurate barrel. The scar uses a long life hammer forged barrel. I decided to go with a hand lapped button rifled stainless. At the rate I shoot .223 I will never wear it out and the accuracy exceeds hammer forging. Due to the panic buying I had to pay a bit more for parts than normal and unfortunately Lilja decided to start making pre-chambered AR barrels a month after I bought mine which cost me $150. My new AR's name is Lily and these are the parts she is made out of:

Handgaurd: Daniel Defense lite rail 7.0 $279.00
http://www.danieldefense.com/?page=shop/detail&product_id=60

Gas system: Adams Arms AR15Fix piston system (includes front gas block and carrier key) $499.00
http://www.adamsarms.net/order.html

Buffer: Custom designed by me to prevent carrier tilt (it works by the way). Buffer is lathe turned stainless. The prototype cost $150 to have made.

Trigger/hammer group: Complete JP Fire Control Package for .154 Small pin receivers $179.95
http://www.jprifles.com/1.4.8.1.php

Bolt Carrier: JP Full mass Stainless Carrier with key $180
Bolt: JP Bolt Carrier Completion Kit with leitner wise bolt $159.95
http://www.jprifles.com/1.4.7.php

Barrel: Lilja 16.5 M-4 416 stainless $315
Installation chambering and shipping $260
http://www.riflebarrels.com/products/ar.htm

Upper receiver: Bushmaster V match flat-top upper receiver assembly (complete no bolt or carrier) $190 +26.50 for the charging handle
http://www.bushmaster.com/products.asp?cat=601

Lower receiver: Bushmaster xm15-e2s lower receiver assembly $349.00
Locally purchased

Flash hider: Vortex model 1001V $51
http://www.smithenterprise.com/products06.html

Grip: Command arms AR15 Tactical Grip $26.00
http://www.cgwgun.com/Command-Arms-Tactical-AR15-Grip__G27.aspx

Rail covers: Magpul XT Rail protectors – Black $11.95
http://www.cgwgun.com/Magpul-XT-Rail-Protectors__MAG012.aspx

Command Arms ACP Adjustable Cheek Piece for CBS Carbine with Picatinny Rail for Collapsible Stocks $40
http://www.commandarms.com/product.asp?pID=228

Gear sector GS-2P Sling and QD Swivel HD Rail Mount. $75.01
http://www.gearsector.com/

Scope: Leupold Mark 4 CQ/T 1-3x13mm $639
Ebay (Marshfield Arms)
Mount: leupold Mark 4 CQ/T Throw Lever Base (A.R.M.S. MFG) 107.97
http://www.opticsplanet.net/leupold-mark-4-cq-t-throw-lever-matte-mount-57506.html

Tactical light: Surefire M951 Kit02 (light, mount, pressure switch, IR filter, and batteries) $157.50
Ebay

Gun price without sling, scope or light comparable to new SCAR: $2741.25
Gun total as usually equipped: $3720.73

I feel I accomplished my purpose even if I had to design a piece myself to get there. Interestingly the price came to within a few dollars of the scar. This was not planned. I expected it would be significantly cheaper. I would not trade this gun for any SCAR or any AR ever made. I am very satisfied. And now, for those who have patiently waited. I give you the Pics.




 

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Very nice setup. Did the Bushy lower come complete, and then you swapped out the trigger group and replaced the stock?
 

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I was wondering if you could've saved some money if you kept a standard pistol grip/trigger group.

Looks nice, but the stainless barrel isn't very good for a tactical purpose (I know that's not its intended purpose and you could duracoat it).

Are you going to put a foregrip or bipod on it?


Also, I like the reticle of that scope, but it's a bit long for my taste. I'm not sure how I feel about it.
 

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It's certainly a nice setup, but (not surprisingly, coming from me), if you wanted something to compare with the SCAR, you should look in to the XCR.

Have you obtained any accuracy results at 100 yards? :shock:
 

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Discussion Starter · #6 ·
Yes, the lower was complete. That is the only way I could find one locally because of the panic. I did swap out the trigger. The factory one was poor even for an AR trigger. The trigger I added is the tactical 4lb jp which I felt was a good accuracy / reliability compromise. The stock is actually still the original bushmaster with an added adjustable comb and anti-tilt buffer. I haven't had the chance to test the rifle at more than 25yds yet because there is snow on the ground and it is cold here in Ohio. This weekend looks promising though as it is supposed to hit 50. I am excited as I think with a good set of bags and prone I might get 1/2 moa. As for the stainless barrel. If I ever need to I'll duracote it or spray it with krylon but since the zombies haven't started attacking yet and I like shiny things Its going to remain unaltered for now. I can't stand using foregrips as they just feel unnatural to me so it's not getting one of those. As for the bipod, I have one and I just haven't ponied up the money for the rail adapter for it. I have been shooting off of a bag which I like better anyway. Some time I'm sure I'll get the adapter though. Even if it is only to make the pictures look more tacti-cool.

Also, for those of you wondering, I shot that group with a zeiss conquest 4.5-14x scope. Since both scopes mount with throw levers it is an easy switch out.
 

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It may have cost you as much as a scar, but you obviously had more fun customizing it yourself, which is worth the money to me. Nice job.
 

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I mean no disrespect, but I can't believe how much that rifle costed....
It is very nice though.
 

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How many rounds do you have through it? Do you notice any carrier tilt yet?

That's the only reason I haven't done a piston upgrade on any of my AR's. Until they start selling modified buffers to reduce or eliminate carrier tilt, they just eat up the metal in the buffer tube.
 

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Discussion Starter · #11 ·
To address the buffer tilt issue.

For those who do not know. Buffer tilt in a piston gun is a consequence of of the operating rod interfacing with the bolt carrier out of line with the center of the bolt. The distance to which the force is out of line with the center of the bolt carrier is called the moment arm. Because, on a piston system, this distance is not zero (it is zero for a DI gun) the carriers are often tilted by the off center force and consequently dig into the buffer tube as they travel rearword. The severity of this problem varies. Some folks see little wear, some have horrible gauging of the buffer tube. Some folks even have reported broken locking lugs or bolts that they attribute to the tilt. Even with un-modified piston systems that do not mitigate tilt the bulk of my research has concluded that the piston is still considerably more reliable than the DI system.

That being said. Why live with it if you don't have to. Many of the piston makers have gone to the trouble of putting skiis on the bottom of their carriers to limit tilt (HK, LWRC, and now adams arms with the new carrier.)

While these systems help it is my contention modified buffers work better since the bolt carrier starts its rearward motion locked into the buffer which interfaces with the carrier tube smoothly and evenly preventing excessive buffer tube wear. The force normal between the carrier tube and the buffer prevents any tilting at all. I was not the first to think of this. At least 3 different people independently came to this solution. This is not surprising when you consider all inventions are really just slight additions to combinations of previous inventions. Invention theory maintains simultaneous independent invention to be the norm not the exception. Obviously this calls into question the stated purpose and efficacy of this countries patent system but that is a soap box for another day.

Anyhow, I have attached a picture of the buffer I designed as well as a couple of photos of the testing I did. For the testing white stickers were attached to the bottom tail of the bolt carrier. These stickers allowed evidence of tilting and wear to be apparent after only a few rounds. The pictures shown are of the stickers after the test. You will see that in the test with a normal buffer the sticker is torn. With the anti-tilt buffer it is unmolested. The buffer works quite well. It is my understanding that one of the AR15.com members "OTSS" is in the process of patenting this buffer so any sales would have to go through him. It's a shame since I understand the first person to actually come up with the idea was spikes tactical they just never did anything with it. Spikes is already a manufacture of Buffers so had they produced the product it would already be available in mass and for a good price.

[Moderated by TH - patent pending violation, some content removed to protect patent holder vis a vie applicable patent laws]





 

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PWS had an interesting solution to the carrier tilt issue.

Personally IMHO there is nothing wrong with a DI AR.


Cool looking rifle BTW. :?
 

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Discussion Starter · #13 ·
My apologies for the slow response to folks pm's regarding the anti-tilt buffer. I think I am all caught up now though. This weekend the weather was good and I had a chance, for the first time, to take Lily to the 100 yard outdoor range. I tested her out with 3 different hand loads I made up. This is the best group of the day. .68 moa with 60 gr nosler ballistic tip varmint rounds pushed by 23.9 grs of reloader 15. Most groups with this load hovered around 1 moa. I am not convinced I have reached the full mechanical accuracy of the rifle at this point. Since I built the rifle as primarily a close to mid range weapon it is very light weight and has a fairly heavy (4lb) trigger. It is not as solid on the bags as a .308 bolt gun and I think perhaps I am the weak link at this point. Also it was a pretty windy day and when it would gust my groups would string horizontally a bit. As I continue to fiddle with loads I may try saddle bagging some weight to the gun as well to help me keep it steady. I'll post if I manage to get the groups down below .5 moa.

 

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Discussion Starter · #15 ·
Doesn't seem like photo bucket is resizing the pics like it says it does. Sorry bout that. In the future I will resize them before uploading. My monitor is 1680 x 1050 so I didn't notice the problem.
 

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_47_ said:
Doesn't seem like photo bucket is resizing the pics like it says it does. Sorry bout that. In the future I will resize them before uploading. My monitor is 1680 x 1050 so I didn't notice the problem.
When I upload to photobucket there is a little drop down size selector that is set to 800x600 by default. Are you saying you don't see the selector or that it just isn't working right now?
 

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Discussion Starter · #17 ·
I made sure that selector was set to 800x600 for all my pics. I even went back later with their resizing tool and resized them all to 800 x 600. The pics still register as much larger when I click on their details here on the FN forum. Go figure.
 

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Where (is) are the following:
1) Ambi controls
2) Folding stock
3) QCB
4) Iron sights

I read it as being equal, if not "better" than A SCAR. I don't see it. Don't get me wrong, I think it's nice and all, but I think you could have gotten an XCR and came closer to a SCAR without spending as much as you did.

BTW, I have the same scope :? on my FS2000, without the Q.R. mount.

If you're happy, then... :?

PEACE THROUGH STRENGTH (who said it?)
 

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_47_ said:
I made sure that selector was set to 800x600 for all my pics. I even went back later with their resizing tool and resized them all to 800 x 600. The pics still register as much larger when I click on their details here on the FN forum. Go figure.
Yeah, it must not be working right now. Another member here and a guy on another forum also have stated the resizer isn't working.
 

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Discussion Starter · #20 ·
Where (is) are the following:
1) Ambi controls
2) Folding stock
3) QCB
4) Iron sights
fair questions
1) I don't really dig ambi controls. I am right handed and always operate the safety and mag release the same way. Perhaps if I trained for several different techniques the ambi release would make sense but I don't so I don't really see the point. Conversely I also am not bothered by the scar having a charging handle that can only be operated from one side of the rifle. Although, I would switch it to the right hand side (Yes I know it can be changed easily). I would also prefer a non reciprocating charging handle on the scar but thats a little bit nit picky.
2) Again, I don't really dig the side folding stock. Collapsible is fine while the side folding stock does have and advantage for in vehicle Maneuverability in order to get this they had to move the buffer spring. That raised the height of the receiver. To be honest, given the choice of a lower receiver or a side folding stock I pick the lower receiver.
3) A quick connect barrel is a nice feature for full auto fire but I do not have an RDIAS. I really don't see the point for a semi auto gun. Do you carry around a second barrel in the field for a quick change?
4) Yea, I could slap a buis on it. Really, I could pretty easily buy a better one than the scar has since the one is has looks a little weak to me. I have thought about it but I have faith in my Leupold and I don't want the extra weight.

As for the XCR, the reason I argue that this AR bests the scar is that while it approximates the scar's features in most categories (in some cases better, such as the trigger, in some cases a little behind like the side folding stock, in some cases just different such as a match button stainless barrel vs. a long life hammer forged) it retains the huge spare parts base that the AR enjoys. Aside from the gas system all parts are interchangeable with milspec and the gas system can be removed and reverted to DI if need be with minimal difficulty. If you ask me the spare parts advantage is a little bit of a trump card. The XCR, while a nice rife, is in the same boat as the scar in this department. Actually, it is worse off since I expect in 20 years our forces will be using the scar and its parts will be as common as AR parts provided they are not banned.

Who knows, maybe when I get the scar I will think it is hands down better but I kind of doubt it. Lily really kicks ass.
 
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