I just sold a rifle and want to add another PWS rifle to the herd.  This will eventually host a suppressor but for now will run without.   I have an SBR'd  POF lower that I could top with a PWS upper.  Or should I go with a complete PWS rifle?  I know there are ballistics benefits of the 12" barrel but any other reason I should go w/ the 12" over the 10.75?

Less wear/tear on the suppressor. Sub 11'' barrels are a bit harsh on the suppressor.

The difference in muzzle PSI between the 12.75 and 10.75 is going to be minimal, probably in the 2,000 psi range if that.  A 10.75 is 10,500psi, and a 16 inch is 5500 to 6,000 psi....so the 12.75 will fall in between there.  

If you are comparing a 10.75 to a 7 to 8 inch, that is where there is a 40% difference in muzzle pressure and resulting wear on the can.  

Basically, don't worry about wear on a 10.5 inch or longer barrel.....but definitely worry about it on anything less than 10inches.

I asked this same question to PWS directly last year. I was told that the MK12 will have smoother recoil and would be less harsh on the can than the MK10. I wasnt in a hurry, and he knew it. I waited and went with the 12.

I picked up the 12 myself and love it. Saving up for an LWRC IC lower now, to attach to this and make that my SBR build.

I like the 10.75.  If you are going short, go short.

Thanks for the excellent replies.  I'm leaning towards the 12".  Still compact enough w/ a can and perhaps a little softer shooting.

It really is the perfect length (To me). Holds great ballistics, out to 400 meters, but still is compact enough to use for closer range encounters.

Depending on how you prefer to grip the rifle, you may prefer the 12.7 as well, that is if you prefer the off hand arm extended and gripping the far end of the rifle.

If I could have only one carbine for everything, no question the MK112 would be the one.

.223 or 300BLK?  You're going to get a lot more bang out of 300 in a 12" but the ammo will be more expensive.  Also, suppressed experience will be much better.  I just got a 300BLK PWS upper (16in) and I don't plan on running .223 for anything but plinking now.

I haven't played with a MK12, but my MK10 is a dream to shoot. Don't let perceived recoil be the deciding factor. The PWS 10.5 is a mild shooter and has rapidly become my favorite rifle.

I'm running the Saker 5.56 which has a warranty all the way down to 7.5" full-auto. Here it is on my PWS Mk110. Go short.

I thought only the 762 Saker was good down to 7.5"???

Nope, other way around. Only the 5.56 version has the Hoplon blast baffle/is rated for 7 inch barrels.

Im a fan of the PWS 12.75"  ... does everything well!

WOO HOO!! I finally got the funds for the sale of my other rifle and now I can move forward with the purchase of a new PWS.   I'm still teetering on the fence of the 10.75 or 12.75" upper.  I see that both of those uppers come with the Triad muzzle device.  I wonder why they don't have the FSC 556 muzzle device.  I have the FSC on my 16" PWS and it is awesome.  I would love  the FSC on my new upper.  Would that be a great or stupid idea?   I'm guessing PWS uses the Triad for a reason.   I'm spending big money tomorrow so any final input from you PWS fans on the 10.75 vs the 12.75" upper.  This upper will host a can at some point but will run as is for a while.   Go.

10.75 for sure!!! if you are going SBR, might as well have it short. honestly i think 10.75 is the ideal length. velocity is still up there, its more maneuverable than a 12" and the balance of the PWS 10.75 rifle is great.

check out these ballistic numbers from hornady. you will see the difference for their rounds in different barrel lengths. (all these length barrels will be effective). I have seen people shot with .223 from 7.5"-16" and believe me shot placement is key but they all work. the effective range talk is annoying because most people are not shooting aggressors at 400 meters, second, MOST people mount an aimpoint or eotech on their rifle, meaning they are not taking shots past 250 meters. A 10" gun with good ammo will do it all when it comes to under 200 meter shooting.

http://www.hornadyle.com/products/rifle-ammunition/223-remington/62-gr-tap-barrier

If your purpose for this rifle (which I'm assuming it is), is to have fun at the range and maybe home defense/self defense, then I would definitely do 10.75"

In terms of suppressors, you will not ruin your can with a 10.75". Most people don't shoot enough to really ruin a can. I have been trying to destroy a YHM phantom and its just not going to happen. Im out of the country right now but when I get home ill post a video of full auto fire through a 7.5" on my can. if you can afford to shoot enough to ruin a can then you can afford to buy another one.

Get an AAC 556-sd or M4-2000, use the rebate for a brakeout or brake which will help protect it.

you don't need a PWS complete rifle. keep your SBR POF. Lower if pretty much all personal.
Don't get a POF upper though.

I love the 10.75" PWS and I really think you will too. great shooter. honestly it depends on what other upper you have??? If you only have one i would do 10.75". I have 10 uppers from 7.5-16" and I find myself always using the 10.75 or the 7.5" when shooting suppressed.  Un-suppressed I like 14.5".

Thanks for your feedback. My only apprehension about the 10.75 was the slight increase in felt recoil/ muzzle rise.  I wouldn't want to sacrifice quick follow up shots for a slightly shorter barrel.

No, you will be happier with the 10.75". there will not be any more NOTICEABLE recoil and that will also depend slightly on ammo. don't let recoil scare you, training will help with recoil, no training will make a barrel short and a rifle lighter.  I find recoil to be quite personal also. It reminds me of the guys who buy 9mm because it has less recoil than a .40 and they only practice with practice ammo, but then they carry +P+ haha. its .223, if you are older than 14 you should be fine with the recoil on any length AR.

I don't know you, but I personally like the 10.75" better. Especially with an SBR, started with 14.5 and then went to 11.5" and then 7.5" haha, you will want to go shorter after shooting the 12" for a little while. Might as well just start with the 10.75"

If you put a brakeout 1 on it, its a nice soft shooter.

I like the way you think


No, you will be happier with the 10.75". there will not be any more NOTICEABLE recoil and that will also depend slightly on ammo. don't let recoil scare you, training will help with recoil, no training will make a barrel short and a rifle lighter.  I find recoil to be quite personal also. It reminds me of the guys who buy 9mm because it has less recoil than a .40 and they only practice with practice ammo, but then they carry +P+ haha. its .223, if you are older than 14 you should be fine with the recoil on any length AR.

I don't know you, but I personally like the 10.75" better. Especially with an SBR, started with 14.5 and then went to 11.5" and then 7.5" haha, you will want to go shorter after shooting the 12" for a little while. Might as well just start with the 10.75"

If you put a brakeout 1 on it, its a nice soft shooter.

Thank you

Honestly if you weren't going to suppress it then id say maybe 12" or even 14" but with a can you will defiantly want the 10.75".

Also, if you are running it without a can, keep the triad fh that comes with it, i personally prefer that over the brakeout.

again I'm out of town, but heres what i could find on my computer:
PWS 10.75" with M4-2000.  you wouldn't want that rifle any longer when suppressed (for ranges of under 200 meters).

Having now owned most of the PWS lineup, id recommend the MK110 (10.75").. it functions flawlessly and is plenty accurate. It was designed to be used with a can as well, so, youre good to go either with or without suppression.

The PWS Mk107 is actually a 7.75" barrel, not 7.5"

This was my choice. Will eventually be an SBR with a can.

Seriously considering buying the Mk.110 upper for my SBR build. Since it's a piston system do I need to get a specific buffer tube, spring and buffer? I noticed PWS has an enhanced buffer tube and since I won't be buying the whole rifle is it something I need or will the gun run just fine with the parts one would normally use on a DI rifle?

Also it will eventually be running suppressed most of the time.

No

Can use any conventional buffer tube/spring/buffer. I personally opted for the enhanced from PWS, as it came with the built in QD attachment points and eliminated the need of a castle nut.

It has a 4 position adjustable gas block, tune the rifle to the suppressor/ammo that you use. My MK 112 took a bit of tuning but I ended up using a red spring and an H2 buffer and still got lock back on last, while using a Surefire FA556-212 and PMC ammo on gas position 4.

I'm digging on the 10.75".   26" OAL. 7 lbs 9 oz dressed out.  Got a Griffin Armament can on the way for it.

I just shot my 500th rd thru my Mk110 today. Not 1 single failure or hiccup. I've shot a variety of ammo and my liil SBR has performed flawlessly.  I'm very impressed with its performance, balance,  and function.