- Thread starter krw
- Start date
Couple things...there is no "commercial" vs. "mil-spec" tube as to rifle/A1/A2 receiver extensions/buffer tubes. They are ALL the same.
If your AR-10 is currently wearing a collapsible stock that came from the factory that way, it is a "mil spec" diameter extension, but an extended length one that will NOT allow and AR-15 collapsible stock body to fully collapse on it because it is longer than a standard AR-15 tube. If you do have a collapsible-style/carbine receiver extension, you will need to remove it, the castle nut and endplate, and the carbine buffer and spring and replace them with a rifle-length/A2 extension with an appropriate AR-10 RIFLE buffer and spring to run the PRS type stocks. If its a collapsible stock for the AR-15, just realize that without swapping to an AR-15 receiver extension and a shortened buffer, you won't be able to collapse the AR-15 stock all the way on the Armalite proprietary AR-10 carbine buffer tube.
As to the Magpul AR-15 PRS stock...NO, it will NOT work on an AR-10 without modification if you raise the cheek riser even slightly. This is because the AR-15 PRS has a longer cheek riser section than the AR-10 model that extends toward the receiver...with it raised, the longer charging handle of the AR-10 will make contact with the riser on the AR-15 model and not allow you to properly charge/cycle the rifle. Thus...that's why Magpul makes an AR-10/SR-25 version of the PRS.
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I didn't mean to dissuade you from making the move to the CTR. A mil-spec CTR WILL work with your current receiver extension, but it will not fully collapse like it would on an AR-15 receiver extension (it'll be ~0.75" or so short of fully collapsing to be specific). This is NOT a big deal unless you really need to run the rifle with the stock shortened up that tight or the aesthetics of the rifle with the stock not fully collapsed bugs you that much. Functionally...the CTR will mount right up and run just fine.
If you DO want it to collapse fully, you'll just need to swap out the receiver extension to a basic, AR-15 mil-spec tube, as well as move to a special, shortened .308 Carbine buffer like those offered by Clint Butler (a.k.a. - Slash's Heavy Buffers), along with a modified AR-10 carbine buffer spring.
Hi all (I'm new around here...)
Just put on a PRS stock on my 308 and I have an "almost new" Magpul ACS-L left over, including the matching mil-spec carbine extension tube (AR15 length), "short" 308 buffer and buffer spring. I can also toss in a Magpul ASAP sling mount since I no longer have use for that.
Interested? PM me with a fair offer (parts are almost new and came off my week-old CMMG MK3).
... and yes, it does collapse fully.
Just put on a PRS stock on my 308 and I have an "almost new" Magpul ACS-L left over, including the matching mil-spec carbine extension tube (AR15 length), "short" 308 buffer and buffer spring. I can also toss in a Magpul ASAP sling mount since I no longer have use for that.
Interested? PM me with a fair offer (parts are almost new and came off my week-old CMMG MK3).
... and yes, it does collapse fully.
Yes...that's the difference between the two.
HOWEVER...in order of my preference with using an AR-15 model on a .308 AR would be:
1) USE THE RIGHT PART/TOOL FOR THE JOB!! There are AR-10 PRS models out there. If you can tell me what color you are wanting, I may be able to put you on the trail to one so that you don't have a hacked-up stock on your rifle. Trust me when I say that they are pretty fugly when modded in that fashion!
Just by way of example, here's a couple links to IN STOCK AR-10 Magpul PRS stocks:
PK Firearms | Online Store (OD Green in stock and ready to roll...look at very bottom of the page...good company that I've done business with for YEARS).
MAGPUL AR-10 PRS Stock - Black (Black in stock...DSG is one of Magpul largest stocking dealers in the US and they are also GTG).
MAGPUL AR-10 PRS Stock - Dark Earth (FDE in stock also)
2) Use a DPMS Buttstock Extender to get you the extra clearance you need (and then some) instead of hacking up your stock. See here: DPMS Buttstock Extender 1 AR-15 Aluminum Matte
and last and certainly least...
3) Hack up an AR-15 PRS to work on your AR-10.
Good luck to you (and again...get the RIGHT PART the first time and avoid the dremel route)!!
Yes...that's the difference between the two.
HOWEVER...in order of my preference with using an AR-15 model on a .308 AR would be:
1) USE THE RIGHT PART/TOOL FOR THE JOB!! There are AR-10 PRS models out there. If you can tell me what color you are wanting, I may be able to put you on the trail to one so that you don't have a hacked-up stock on your rifle. Trust me when I say that they are pretty fugly when modded in that fashion!
Just by way of example, here's a couple links to IN STOCK AR-10 Magpul PRS stocks:
PK Firearms | Online Store (OD Green in stock and ready to roll...look at very bottom of the page...good company that I've done business with for YEARS).
MAGPUL AR-10 PRS Stock - Black (Black in stock...DSG is one of Magpul largest stocking dealers in the US and they are also GTG).
MAGPUL AR-10 PRS Stock - Dark Earth (FDE in stock also)
2) Use a DPMS Buttstock Extender to get you the extra clearance you need (and then some) instead of hacking up your stock. See here: DPMS Buttstock Extender 1 AR-15 Aluminum Matte
and last and certainly least...
3) Hack up an AR-15 PRS to work on your AR-10.
Good luck to you (and again...get the RIGHT PART the first time and avoid the dremel route)!!
Thanks ORD. I hear you and agree. Just looking for ways to cut a few bucks from my build. I love the PRS on my AR15 and on my Savage 10BA-LE.
Started adding up parts for my build last night and I am into it for about $1739 already without a stock (including some parts that I still have to buy). This might not be much for some guys but I am buying this a piece at a time when I have some extra dollars. Just ordered the 24" Lilja barrel that I have been saving for (most expensive part). Still need the lower (doing an 80% Tactical Machining lower and it was a 8-9 month lead time when I ordered - with about 3 more months to go
). Local place has "build parties" where you bring in your lower and put it in the jigs on their CNC machine then press start. They charge like $65 for this. Cost comes out about the same as buying a finished DPMS lower without all the Kalifornia FFL hassle/charges. Just have to use a "bullet button" with 10 round mags while shooting it here and can never sell it. BTW Joebob outfitters has the .308 PRS for $209 with free shipping over $99 and also a 5% discount for Military/vets/LEO. Just out of black color right now. They are GTG too.+1 on Slash's buffer and spring
I use a slash XH buffer and slash custon AR10 spring with a Magpul UBR stock
16" carbine
works fantastic
I use a slash XH buffer and slash custon AR10 spring with a Magpul UBR stock
16" carbine
works fantastic
If I was you, I would try the Battleline industries SAPR attachment on your CTR. Then you have the best of both worlds; collapsible stock, lighter, adjustable cheek weld, heel height, (as well as other adjustments). I have one on my setup, and like it.
P.S. Rainier Arms has them
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i would take ORD's advice. His always spot on. He has helped me out with his advice more times than I can count.
I like the Magpul UBR it is a very nice stock it allows u to keep ur eyes on target while moving into comfortable shoulder range.
Nothing at all wrong with the UBR (aside from perhaps the weight which is HIGH for a "collapsible" type stock, but still lighter than the PRS by around 5-10oz depending on the buffer you run). As with all other collapsible stocks on the AR-10/LR-308 platform rifles when running an AR-15 collapsible stock/receiver extension (including the shortened "Entry" extension the UBR is built around), just be sure to get a proper AR-10 "short" buffer to go with it as the AR-15 and Armalite-type AR-10 CAR buffers are too long to work with the longer carrier of the AR-10/LR-308.
I used the JP silent captured spring. Just cut off the Delryn spacer to the appropriate length and run it.
Thanks, but I just picked up a new AR10/LR308 PRS from Deltaoutdoorsman.com for an awsome low price. Shipped the same day I ordered it and showed up in just a couple of days. Great communication and customer service! They are GTG!
I'll have to store that tidbit away for future reference. Never heard that before now, but its nice to know. Out of curiosity, what is the cost from Magpul and what all is included in the kit (I'm assuming its just the shortened riser, but I don't know)?
I have both stocks on mine and prefer the PRS
