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The4thHorseman
23 January 2008, 19:17
Ok so here is the mission. To build my last SHTF ultimate zombie-killer without my commander-in-chief finding out!:rolleyes: I envision a VIS middy on a Magpul lower, Magpul 93B stock, Magpul MIAD grip, RRA NM trigger and LPK, BCG by CMT and PRI BUIS. What I am not clear on is how do I go about getting the correct barrel(s). I am thinking a 16 and/or 18 inch, slim profile with a regular A2 FH. I would be using XM193 ammo and want to effectively engage out to 300-350 meters. Somebody please point me in the most cost effective direction! I also have an optics question...my TA31F I assume would be a no go on this build since its calibrated for a 20 inch. What would be a good optic for my project?? Thanks guys and please pardon my ignorance, I am new in the addictive world of building your own! I hope to pick Stickman's and John from Rainier Arm's brains!!!

Paulo_Santos
23 January 2008, 19:34
I was going to say since you want something to reach out to 300-500 meters, and you plan on using XM193 ammo, and an ACOG that is calibrated for a 20" barrel, why not get a 20" government profile barrel with a 1:9" twist?

Exactly which ACOG do you have? Is it the TA31 (which is calibrated for the XM193 from a 20" barrel), or do you have the TA31RCO-A4?

Also, if you are getting the RRA NM trigger, I'd highly recommed spending an extra $20 and get the WOA tuned RRA trigger.

If you are dead set on a 16 or 18" barrel, get a 16" Government profile Midlength barrel from CMMG, RRA, or Saber Defense.

The4thHorseman
23 January 2008, 19:47
I was going to say since you want something to reach out to 300-500 meters, and you plan on using XM193 ammo, and an ACOG that is calibrated for a 20" barrel, why not get a 20" government profile barrel with a 1:9" twist?

Exactly which ACOG do you have? Is it the TA31 (which is calibrated for the XM193 from a 20" barrel), or do you have the TA31RCO-A4?

Also, if you are getting the RRA NM trigger, I'd highly recommed spending an extra $20 and get the WOA tuned RRA trigger.

If you are dead set on a 16 or 18" barrel, get a 16" Government profile Midlength barrel from CMMG, RRA, or Saber Defense.

I have the TA31RCO-A4. The reason I want to go 16 or 18 is because I want the M4 style of weapon, one that I can use for CQB or carry in a vehicle. I am trying to narrow down what this weapon would be used for. Scenarios would be CQB and as a stand-off weapon. I kinda also want the ability to reach out and touch if necessary. Is such a monster possible??[wow]

NvrenufRR
23 January 2008, 20:04
Ta 31 rco-a4 will be fine out to 400-600 yards.
Its calibrated for 1:7 twist 20" barrels firing M855 62gr SS109, mounted to a flattop upper with either ARMS or LaRue mount.
I would opt the 18" barrel configuration, it will be fine for CQB and also get a little extra velocity over the 16'.
Try to adopt at least 1:8 twist rate if your not able to find 1:7 SPR.
You will not get the accuracy you waant from XM 193 out of the Ta-31RCO-A4, you may want to look at the TA-11E or Ta-01 NSN. The TA-11 is a bit larger of a unit and .5 magnification less, but both are calibrated for 20" barrels and flattop uppers and XM 193 as I recall.

I have 4 ACOGs, each of the series being calibrated for different barrel lengths, twist rates, bullet weight and mounting location.
You will be fine using your choice, but if you want to venture other routes of ACOG's I would contact Trijicon directly, they will answer all your questions. They are local for me, so I am able to refernece all the info I need anytime, but even outside of local, a phone call has answered any and all questions I have ever had. Just call them with your requirements and they will specify which series will work for your platform.
Good luck.

Another optic to opt for would be USO 1 and 4 power. Awesome quality glass, better than ACOGs, and it has gr specific adjustment knobs, illuminated reticle options, and ranging capabilities very similar to the ACOGS.
Good luck.
Nice choice of a build also, looking forward to pics.

The4thHorseman
23 January 2008, 20:14
Ta 31 rco-a4 will be fine out to 400-600 yards.
Its calibrated for 1:7 twist 20" barrels firing M855 62gr SS109, mounted to a flattop upper with either ARMS or LaRue mount.
I would opt the 18" barrel configuration, it will be fine for CQB and also get a little extra velocity over the 16'.
Try to adopt at least 1:8 twist rate if your not able to find 1:7 SPR.
You will not get the accuracy you waant from XM 193 out of the Ta-31RCO-A4, you may want to look at the TA-11E or Ta-01 NSN. The TA-11 is a bit larger of a unit and .5 magnification less, but both are calibrated for 20" barrels and flattop uppers and XM 193 as I recall.

I have 4 ACOGs, each of the series being calibrated for different barrel lengths, twist rates, bullet weight and mounting location.
You will be fine using your choice, but if you want to venture other routes of ACOG's I would contact Trijicon directly, they will answer all your questions. They are local for me, so I am able to refernece all the info I need anytime, but even outside of local, a phone call has answered any and all questions I have ever had. Just call them with your requirements and they will specify which series will work for your platform.
Good luck.

Another optic to opt for would be USO 1 and 4 power. Awesome quality glass, better than ACOGs, and it has gr specific adjustment knobs, illuminated reticle options, and ranging capabilities very similar to the ACOGS.
Good luck.
Nice choice of a build also, looking forward to pics.

Thanks for the suggestions. An 18 inch was what I was favoring. Also if my TA-31RCO-A4 will work on this set up I would be most happy! This build is gonna break the bank as it is and it would truly suck if I had to get another optic ( though that Elcan Specter would be SWEEET!)

Stickman
24 January 2008, 10:35
Ok so here is the mission. To build my last SHTF ultimate zombie-killer without my commander-in-chief finding out!:rolleyes: I envision a VIS middy on a Magpul lower, Magpul 93B stock, Magpul MIAD grip, RRA NM trigger and LPK, BCG by CMT and PRI BUIS. What I am not clear on is how do I go about getting the correct barrel(s). I am thinking a 16 and/or 18 inch, slim profile with a regular A2 FH. I would be using XM193 ammo and want to effectively engage out to 300-350 meters. Somebody please point me in the most cost effective direction! I also have an optics question...my TA31F I assume would be a no go on this build since its calibrated for a 20 inch. What would be a good optic for my project?? Thanks guys and please pardon my ignorance, I am new in the addictive world of building your own! I hope to pick Stickman's and John from Rainier Arm's brains!!!


If you are looking to find resources like the above without your off duty supervisor finding out, I wish you the best of luck. You've got some expensive items plugged into that equation!

You may have a hard time finding the Magpul M93 series stocks as they have been out of production for awhile. The new UBRs from Magpul are out in preproduction status, and I would expect them in full production before too much longer.

Recently I've been doing work with 16" barrels for intermediate distance, and I've been very happy with them. The barrel length still works for close in maneuvering, but allows engagement out to farther distance without much trouble. Not that the 18" would be a bad choice at all, but its a hard call to make without knowing your minimum distances that you wanted to be effective at. Shorter is easier, but so is lighter.... and everything is a trade off.

For optics, you may want to consider a low end variable. Right now the world is a buzz with people being in love with the Short Dot, and infrequently is the price mentioned. To my eye, the SD falls flat, but others love it. There are a lot of low powered variable optics, and to me the Trijicon Accupoint still offers the best bang for the buck. The low end 1.25 power allows effective close in use. The 4x should give you decent magnification for intermediate distances.

Stickman
24 January 2008, 10:42
I don't have anything with a VIS, but here are two pictures that show a similar concept.



http://stickman.rainierarms.com/galleries/Magpul%20II/IMG_9257%201028%20Stick.jpg


http://stickman.rainierarms.com/galleries/Magpul%20II/IMG_0026%201028%20stick.jpg

John Hwang
24 January 2008, 11:46
I wouldn't naturally put VIS & Zombie Killer together.
Generally speaking, I would spend the money on the VIS & high end match barrel if I was interested in ultimate accuracy (matches & such) If you are looking for a zombie killer, and want distance, you can look at the 6.8SPC. If you are on budget, take a look at the 16-20" Barrels from Ko-Tonics. You could build a rifle for 1/2 to 2/3rds the cost and get to your goals.


If you are buying the billet upper for looks, then go for it. If you are buying it to make the ultimate weapon, I really think that's over rated.

The4thHorseman
24 January 2008, 15:39
Thanks Stick and John for chiming in. I already have a M93 for the project. My malfunction is that I am driven by looks first, then performance. I first saw the VIS and said I must have it. And the Magpul Lower?? Well enough said. I decided that these two components would be the base for my do-all be-all AR platform. I know I am looking at about $2000 for this project but I work hard for my paycheck and I feel that I deserve a toy the way that I want, while at the same time being able to be combat effective for SHTF. As for my C-in-C, I will have to carefully negotiate that terrain in order to achieve a tactical advantage! :)

TigerStripe
24 January 2008, 16:17
I wouldn't naturally put VIS & Zombie Killer together.
Generally speaking, I would spend the money on the VIS & high end match barrel if I was interested in ultimate accuracy (matches & such) If you are looking for a zombie killer, and want distance, you can look at the 6.8SPC. If you are on budget, take a look at the 16-20" Barrels from Ko-Tonics. You could build a rifle for 1/2 to 2/3rds the cost and get to your goals.


If you are buying the billet upper for looks, then go for it. If you are buying it to make the ultimate weapon, I really think that's over rated.

What is over rated? Just my usual curiousity...


TS

John Hwang
25 January 2008, 08:22
I don't believe a billet upper gives an average shooter (meaning 98% of shooters) any difference in accuracy. You could probably argue about the last 2% as well. It's all based on the theory of billet uppers/lowers holding better tolorences than forged uppers/lowers. This may be true but from my experience, I haven't noticed any real world difference. To further elaborate, I've noticed just as many billet inconsistencies (products that needed to be returned due to things being out of spec) as forged inconsistencies. The inconsistencies are from multiple billet suppliers so I wouldn't say it's shop specific.

As far as the barrels,
Generally speaking, SS barrels are profiled with accuracy in mind so they are generally heavier. If I was building a "Zombie" gun, I would want something a little lighter.

The4thHorseman
25 January 2008, 11:03
If you are looking to find resources like the above without your off duty supervisor finding out, I wish you the best of luck. You've got some expensive items plugged into that equation!

You may have a hard time finding the Magpul M93 series stocks as they have been out of production for awhile. The new UBRs from Magpul are out in preproduction status, and I would expect them in full production before too much longer.

Recently I've been doing work with 16" barrels for intermediate distance, and I've been very happy with them. The barrel length still works for close in maneuvering, but allows engagement out to farther distance without much trouble. Not that the 18" would be a bad choice at all, but its a hard call to make without knowing your minimum distances that you wanted to be effective at. Shorter is easier, but so is lighter.... and everything is a trade off.

For optics, you may want to consider a low end variable. Right now the world is a buzz with people being in love with the Short Dot, and infrequently is the price mentioned. To my eye, the SD falls flat, but others love it. There are a lot of low powered variable optics, and to me the Trijicon Accupoint still offers the best bang for the buck. The low end 1.25 power allows effective close in use. The 4x should give you decent magnification for intermediate distances.

Hey Stick..can you tell me more about the 16 inch barrels you have been working with??

NvrenufRR
25 January 2008, 13:07
Most match barrels of 16" or longer length will give you 1/2MOA @ 100, as sure as the ones Rainier is offering. At 400 that means 2MOA before break in, most get better if properly broken, (Old News).
You can achieve your shooting to 400+ and maintain the ACOG's ballistics you have, but I would suggest M855 for better consistency. The Xm 193 WILL work fine, but you may have to maintain and learn a hold over/under at longer ranges since it is calibrated 62gr, 20" barrel. You are cutting velocity from the Ballistics, (approx 200+-fps). Anything out past, say 600, would require a dramatic holdover, especially with XM 193.

IMO, your build will b fine with RCO, The whole look thing is most important to most people, so build it the way you want or you'll end up building another later.

Another option on a high end match barrel would be getting one with Polyganal rifling, This particular rifling increases velocity and will bring a 16" that much closer to a 20 allistics to farther ranges.
If you can find one, a Carbon Fiber barrel from ABS, will achieve excellent ballistics, be extremely lightweight, cool rapidly, and not heat up and wear like a standard barrel. These are very pricey though and may not be able to interchange with the VIS unless custom made.

TigerStripe
25 January 2008, 14:21
Hey Stick..can you tell me more about the 16 inch barrels you have been working with??


I'm not Stick but I believe this is the barrel he's talking about: http://www.rainierarms.com/?page=shop/detail&product_id=809.


TS

seanmunger
27 April 2009, 01:49
[QUOTE=NvrenufRR;1647]Most match barrels of 16" or longer length will give you 1/2MOA @ 100, as sure as the ones Rainier is offering. At 400 that means 2MOA before break in

ok so I'm a noob in all sences of the word, but I thought a MOA, didnt change over distance. I am under the impression that a 1 MOA is roughtly 1" at 100 yards, 2" at 200, and so on. so a 1/2 MOA barrel will give you 1/2" groups at 100 yards, and 2" groups at 400, it shouldnt change because of the distance, or am I wrong?

I dont want to come across as a jerk or anything I am just a little confused by this post... like I said I'm as new as you can be to shooting sports and I am trying to get as much information as i can before i make a purchase.

Stickman
28 April 2009, 21:26
ok so I'm a noob in all sences of the word, but I thought a MOA, didnt change over distance. I am under the impression that a 1 MOA is roughtly 1" at 100 yards, 2" at 200, and so on. so a 1/2 MOA barrel will give you 1/2" groups at 100 yards, and 2" groups at 400, it shouldnt change because of the distance, or am I wrong?




You are correct.