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wild_wild_wes
10-16-10, 22:30
Which stock do you think is best suited to a precision rifle build- the PRS, or the UBR?

Ak44
10-16-10, 22:36
PRS but YMMV

ALCOAR
10-16-10, 23:44
16"-18"....UBR

20" + ......PRS

imho:)

Joeywhat
10-17-10, 00:09
IMO:

If the rifle will only be used for long range goodness, PRS.

If there's a decent chance for some 'up close' work or anything where the rifle will be used much like a traditional carbine, I'd go with a UBR.

Just what I think.

thmpr
10-17-10, 00:14
16"-18"....UBR

20" + ......PRS

imho:)

This is my rule of thumb.

wild_wild_wes
10-17-10, 00:55
I actually have an 18" SPR type of rifle with a PRS on it right now, but am not convinced it was the best choice. I wanted to get some opinions on this before I went through the trouble of switching it out.

Meplat
10-17-10, 01:28
I guess I'm alone on this, but I personally find the PRS to be Magpul's most useless stock. Now, that's not to say it isn't well made, because it is, but from my experience it just doesn't fit the role it was designed for very well.

To begin, the stock just by itself comes in just under 2lbs. That's a lot of excess weight to put on your gun. My next beef with it is the adjustable comb. While nice, I don't really find it necessary or useful for the majority of AR mount and optic combinations. On top of that, the comb is so far back in order for the charging handle to clear that it overshoots most scopes with 2-3" of eye relief. The comb also makes it so that, in my experience, you need to fully or almost fully extend the adjustable length of pull to get a comfortable stock and cheek weld that doesn't feel cramped. Next up is the sling mounting options. All you get is a a single slot that really doesn't seem too useful for the types of slings that are out and in use right now. There are, however, aftermarket sling studs that can replace it.

Overall, I'm not too impressed with them, and I don't think I'd use another. The one thing I can say positive is that, as typical of Magpul, the quality is great. And if you plan to use a monopod, this stock definitely would be a wise choice. Beyond that, I find that it's too heavy and doesn't fit the role that it's meant for as well as it could or should.

ryanm
10-17-10, 05:54
Love the PRS--also take a look at the ACE Hammer. Has an adjustable cheek piece plus its a collapsible stock. The buffer tube for the hammer is built like a king tiger tank. It's designed to be used to bust doors (when fully collapsed)

wild_wild_wes
10-17-10, 10:04
I guess I'm alone on this, but I personally find the PRS to be Magpul's most useless stock. To begin, the stock just by itself comes in just under 2lbs. That's a lot of excess weight to put on your gun.


The UBR weighs pretty much the same.

taliv
10-17-10, 12:24
I guess I'm alone on this, but I personally find the PRS to be Magpul's most useless stock. Now, that's not to say it isn't well made, because it is, but from my experience it just doesn't fit the role it was designed for very well.

To begin, the stock just by itself comes in just under 2lbs. That's a lot of excess weight to put on your gun. My next beef with it is the adjustable comb. While nice, I don't really find it necessary or useful for the majority of AR mount and optic combinations. On top of that, the comb is so far back in order for the charging handle to clear that it overshoots most scopes with 2-3" of eye relief. The comb also makes it so that, in my experience, you need to fully or almost fully extend the adjustable length of pull to get a comfortable stock and cheek weld that doesn't feel cramped. Next up is the sling mounting options. All you get is a a single slot that really doesn't seem too useful for the types of slings that are out and in use right now. There are, however, aftermarket sling studs that can replace it.

Overall, I'm not too impressed with them, and I don't think I'd use another. The one thing I can say positive is that, as typical of Magpul, the quality is great. And if you plan to use a monopod, this stock definitely would be a wise choice. Beyond that, I find that it's too heavy and doesn't fit the role that it's meant for as well as it could or should.

not alone. I don't care for them after a couple years of use now. Still love the M93b, CTR and UBRs though.

My biggest beef with them is the sling attachment sucks. If it had a flush cup like the UBR it would be so much better. That aluminum loop is useless for any traditional shooting sling like a 1907, and it makes left/right hand switching a total PITA for any other type of sling. Could just be me though.

I like/want the adjustable cheek piece though. I agree with you that there's a lot of room for improvement there though.

TAZ
10-20-10, 14:33
I love the PRS, but as someone else stated if you intend to use your SPR as something other than just a precision rifle the UBR may be better suited. I'm about to do the same thing. Swap the PRS for a UBR. The UBR feels as stable as the PRS as far as rigidity and I seem to be able to get decent cheek weld with it. Not the same for some ofther collapsible stocks like the ACS.

Utah1
10-20-10, 20:00
A2 or possiably Troys new battle ax

11B101ABN
11-04-10, 16:38
A1 stock.

wild_wild_wes
11-04-10, 20:07
Looking throught the Snipers thread at mp.net, there are a lot of examples of M110s with ad hoc cheekpieces; so some at least have issues with the standard non-adjustable stock:

http://i264.photobucket.com/albums/ii173/USPx4/snipercomp201008.jpg

http://i264.photobucket.com/albums/ii173/USPx4/snipercomp201002.jpg

Some NSW folks seem to like the PRS, which has an adjustable comb:

http://i264.photobucket.com/albums/ii173/USPx4/NSW1.jpg

http://i264.photobucket.com/albums/ii173/USPx4/NSW2.jpg

http://i264.photobucket.com/albums/ii173/USPx4/prs1.jpg

TANGO2072
11-04-10, 20:11
I have to say that I too am considering changing out my PRS for an ACS. But I personally feel that takes away from the "precision" feel...
that makes it more of a "Battle Rifle".

Hard choice...
I run an 18" stock barrel on her w/ a SF brake.
Im torn between the 2.
I love reaching out with her and doubt i'd ever find myself in the "true" need of going all dynamic ( CQB ) with her.
I handle her just fine w/ the PRS during drills, but it does weigh on me.
she's a heavy rifle at 15lbs.

DAM kool-aide choices....

wild_wild_wes
11-04-10, 21:20
Exactly. For a dedicated long-range Precision rifle the PRS sounds great, if you need all that adjustment to get the job done, as might be as seen in the pics above. If you want a CQB Battle rifle- Recce or Afghan- PRS is prolly too heavy. So it looks like the PRS might be suited to an SPR- type rifle. For a 7.62....definitely. I'm still unsure if it is suited to a 5.56 rifle.

TAZ
11-04-10, 21:35
I have to say that I too am considering changing out my PRS for an ACS. But I personally feel that takes away from the "precision" feel...
that makes it more of a "Battle Rifle".
DAM kool-aide choices....

One thing to take into consideration with the ACS is the ability for a good cheekweld. I had one on my SPR and getting a good cheekweld with it was really hard, especially in the prone. It may require the use of a higher scope mount, but if youre the type who likes the tube as close to the bore as possible the ACS is probably not going to be a good choice.

TANGO2072
11-05-10, 02:25
I have to say that I've always been a fan of the SR-25 and MK12 SPR style platforms....
SO why hasnt anyone, yet built a 762 ver of the MK12 yet.
My all time Fav pic;
http://i15.photobucket.com/albums/a393/TAC2/Misc/Guns/SPRCrane.jpg

This is where I'd go w/ my AR-10.
DAM, now it's time to redirect some funding behind HH6.

Meplat
11-05-10, 04:35
Exactly. For a dedicated long-range Precision rifle the PRS sounds great, if you need all that adjustment to get the job done, as might be as seen in the pics above. If you want a CQB Battle rifle- Recce or Afghan- PRS is prolly too heavy. So it looks like the PRS might be suited to an SPR- type rifle. For a 7.62....definitely. I'm still unsure if it is suited to a 5.56 rifle.
In this lowly M4Cer's opinion, I would think the PRS on a .308 AR is even more of a mistake. .308 ARs already get quite heavy with the bells and whistles on them, and adding the weight of a PRS makes my arms tired just thinkin' about it. On a somewhat, but somewhat not related note, LaRue is apparently coming out with a cheek riser for CTRs and other carbine stocks. May be the solution that a lot of people are looking for to keep weight down and retain the flexibility and "adjustability" of a carbine stock while having something a little more scope friendly.

AMC29
11-12-10, 21:05
My DPMS Mini SASS came with the PRS.

I like it, and don't plan on using my SASS as anything but a "see how small I can make groups at the longest distance possible" rifle. I don't think I'd want the PRS if I was going to use it for any other use though.

The UBR looks promising for a DM rifle build.

macman37
11-14-10, 10:40
Have both, prefer the UBR.

The PRS is a nifty stock, but it seems more made for a bench rest rifle with all the adjustments and whatnot.

If I was going with a new build or a replacement for an existing stock I'd lean toward the UBR.

Bolt_Overide
11-14-10, 23:45
I prefer the PRS on anything thats 18 inchs or longer, and the UBR or something else collapsable on anything shorter.

USMC_Anglico
11-19-10, 18:10
In this lowly M4Cer's opinion, I would think the PRS on a .308 AR is even more of a mistake. .308 ARs already get quite heavy with the bells and whistles on them, and adding the weight of a PRS makes my arms tired just thinkin' about it. On a somewhat, but somewhat not related note, LaRue is apparently coming out with a cheek riser for CTRs and other carbine stocks. May be the solution that a lot of people are looking for to keep weight down and retain the flexibility and "adjustability" of a carbine stock while having something a little more scope friendly.

Exactly. A PRS is heavy, adding that on to the weight of a .308 is even more dead weight. If all you are going to do is bench it or shoot prone, then go for it. Once you actually have to pick up and move the .308 and start shooting it kneeling, standing, etc. then it becomes a hinderance. It does nothing that a 16" .308 with a collapsible stock of your choice can't do.

Anyone need a FDE PRS for a .308??? mine is already off my rifle. Sometimes good design/implementation doesn't mean anything when it meets reality.

reiswigt
11-20-10, 22:55
For me, the PRS doesn't feel or look right on a shorter/lighter weapon. The UBR on my AR feels great, but my friends with the PRS just didn't do it for me.

I do like how the PRS on my 20" .308 with bi-pod and a high scope mount feels.

DMR
11-22-10, 19:29
I went through a lot of coa's when I built my DMR before I decided to go with a A1 stock. Key in those choices was it being a carry all day and night design. In the end my rifle intialy came in at just over 10 lbs. I'll try to check the weight again now that I made some changes.

DTHN2LGS
12-04-10, 13:32
Have you considered the Vltor A5 Emod stock for your precision rifle?

There's a thread in the AR General Discussion forum caled "M16A5 Stock by Vltor" about it. I bought one recently on the advice of Bravo Company for the precision rifle I'm very slowly putting together.

.

ErikTaylor
12-09-10, 22:58
I think anytime you're making a dedicated precision rig the PRS wins hands down. Albeit heavy, but does have the features that you'd need to make a consistent sight picture. JMO, YMMV.

TinMan556
12-11-10, 00:20
The PRS

cougar_guy04
12-11-10, 08:46
I have to say that I've always been a fan of the SR-25 and MK12 SPR style platforms....
SO why hasnt anyone, yet built a 762 ver of the MK12 yet.
My all time Fav pic;
http://i15.photobucket.com/albums/a393/TAC2/Misc/Guns/SPRCrane.jpg

This is where I'd go w/ my AR-10.
DAM, now it's time to redirect some funding behind HH6.
[thread hijack]IMO, I think the SR-25 EMC (and the previous SR-25 Battle Rifles) family is very close to that:
https://www.m4carbine.net/showpost.php?p=580592&postcount=41

16" vs. 18" barrel, but still has enough punch to get the job done. I do agree though, the Mk12 was a rifle that caught my attention very early when I started building AR-15s. I'll get my Mk12-ish build done eventually, though I'll be using a UBR instead of a SOPMOD (personal preference).[/hijack]

wild_wild_wes
12-11-10, 11:13
I think anytime you're making a dedicated precision rig the PRS wins hands down. Albeit heavy, but does have the features that you'd need to make a consistent sight picture. JMO, YMMV.

I'm beginning to think so too. I originally had an A1 stock on my SPR, but I put a PRS on to see if it balanced better. It made the rifle heavier, yes, but I found that I needed the cheek riser to get the best cheek weld.

wild_wild_wes
12-18-10, 16:15
Interesting
http://i602.photobucket.com/albums/tt104/vor033/US%20Army%20-%202/281712f8.jpg
A sniper prepares to engage a target during the 2010 USASOC Sniper Competition at Fort Bragg, N.C.

ALCOAR
12-18-10, 16:44
Damn Wes, you find more obscure pics than anyone Ive seen...another really interesting pic:)

I will refrain from my typical bragging spiel about the UBR however for YEARS I have been perplexed as to why "wild" MK 12's don't utilize these amazing precision buttstocks. Esp. on the Mod 0's with A1/A2 fixed stocks. Kinda surprised the shooter is sporting a 20rd. pmag....I have given up on them, perhaps its just a range mag for that type of use only. The shooter basically has that gun completely built A La Carte for his tastes since he has no buis's, a 45 canted secondary mrds, a KAC/LMT ambi selector on a non KAC/LMT lower.

vicious_cb
12-21-10, 20:41
I dont see any reason to use the UBR with the Vltor A5 stock out. The PRS is far too unwieldy for anything other than benching.

Trajan
12-21-10, 23:56
Damn Wes, you find more obscure pics than anyone Ive seen...another really interesting pic:)

I will refrain from my typical bragging spiel about the UBR however for YEARS I have been perplexed as to why "wild" MK 12's don't utilize these amazing precision buttstocks. Esp. on the Mod 0's with A1/A2 fixed stocks. Kinda surprised the shooter is sporting a 20rd. pmag....I have given up on them, perhaps its just a range mag for that type of use only. The shooter basically has that gun completely built A La Carte for his tastes since he has no buis's, a 45 canted secondary mrds, a KAC/LMT ambi selector on a non KAC/LMT lower.

Don't the guys running the Mod 0's have the advantage of the rifle length buffer? What don't you like about the A2 specifically?

ALCOAR
12-22-10, 00:26
What happens if my guns are 100% reliable without having to run the super duper rifle length buffer....is there such a thing as being more reliable than 100%:confused:

Recoil on a .223 just doesn't scare me so I am not looking to turn them into ruger 10/22's and do not need the negligible gain in recoil reduction either.

So if the A2 cannot make my gun more reliable and the recoil reduction amt. is negligible why would I want a dinosaur nonadjustable, very cumbersome A1 or A2 when I can roll with the most advanced buttstock going?

AnimalMother556
12-22-10, 07:26
If I'm not mistaken, there are issues with running a carbine extension tube and buffers with rifle-length gas systems.

ALCOAR
12-22-10, 08:38
So the operators in the field who use the LMT tube/Sopmod(carbine rec. ext. tube) on their MK 12 have more problems than the operators who run an A1 or A2?

AnimalMother556
12-22-10, 20:19
I thought the whole purpose of the Vltor A-5 system was to overcome the shortcomings of putting a carbine receiver extension on rifle length gas guns. I'm not saying they don't work, but apparently issues were encountered. Some of it is touched upon in this thread https://www.m4carbine.net/showthread.php?t=56043. Also some more info here, http://vuurwapenblog.com/2010/09/24/vltor-a5hk416-test-data/. It would seem to be a bigger problem on full auto guns so it may be a moot point on precision semi-autos, but it does seem to be worth noting. Hopefully I'm not stepping on any toes linking to 87gn's blog. If so, I apologize in advance.

wild_wild_wes
12-24-10, 21:57
So if the A2 cannot make my gun more reliable and the recoil reduction amt. is negligible why would I want a dinosaur nonadjustable, very cumbersome A1 or A2 when I can roll with the most advanced buttstock going?

If your main concern was weight, then the A1/A2 would be the best choice.

I had a C1 on my Mk12ish rifle. Put a PRS on it just to experiment, and I found the adjustable comb of great utility in getting the best sight picture. I will be putting a UBR on another rifle; I'll wait to see how I like it before I change my Mk12, if ever. The PRS is heavy, yes, but offers features very valuable in a dedicated precision rifle. Maybe the UBR would be better for a Recce, which is a compromise precision rifle.

Both the PRS and UBR are greatly more heavy than an A1/A2 or regular tele.

Cameron
12-25-10, 07:26
If I'm not mistaken, there are issues with running a carbine extension tube and buffers with rifle-length gas systems.

There are no issues with running a carbine receiver extension on a rifle length gas system. I run, coincidentally, a UBR on my BCM MK12, rifle length gas system and 18" barrel it functions perfectly. It will run with a carbine, H, H1, H2 and H3 buffer. I use the H3 buffer which does approximate the weight of a rifle buffer as the operation feels smoother.

Cameron

dprichard
01-23-11, 07:14
The UBR weighs pretty much the same.

Totally agree on this. I had a UBR and got rid of it because it was so heavy.

MichaelZWilliamson
01-27-11, 06:57
I appreciate the extra weight of the PRS on my Ultramag .50. I also plan to try one on my LAR8.

When you're running that much barrel mass, extra stock mass helps balance things, and reduce recoil, and I can tune the stock for my clothing/optics. I've got marks paintsticked on for scope and iron positions.

I agree it's not intended for a carbine.

Todd-OR
03-07-11, 11:59
I chose a PRS for my 24" rifle due to body type considerations...which haven't been mentioned yet.

For me, humping a 10 lb rifle really isn't a big issue since it is designed to be shot from a prone or seated position not run n gun style and I'm about as hobbyist/amateur noob as you can get with an AR.

But I am 6'7" and have very long arms so the relief that the PRS gave me with the butt plate fully extended and the cheek weld all the way up was just what I needed to get comfy and have a "snap to" sight picture with my scope.

TheInstructor
03-21-11, 20:35
On my 18" 6.8, I went with the UBR and am very happy with it. Excellent cheek weld for me with a Leupold MK4 1.5-5x on it. It may be rumor control right now but I have heard that Larue may be developing a sliding riser for the UBR like they have for the CTR or MOE. That might be nice for some UBR owners wishing for a higher weld.


I actually have an 18" SPR type of rifle with a PRS on it right now, but am not convinced it was the best choice. I wanted to get some opinions on this before I went through the trouble of switching it out.