Looks good !

I'm actually thinking of changing the the grip, not crazy about that gap between the beaver tail and the lower. Maybe i'll pick up a hogue or ergo at Oaks tomorrow.

I got an Ergo grip with a PSA LPK, it is surprisingly comfortable, and grippy..

I have a pink ergo grip I could part with ...

I have a pink ergo grip I could part with ...

 

Shoot me a pm... building an AR for our newborn.

Heh. I'm guessing it is a bit large for baby hands, but if you want it as teething chew toy you can have it

I use Ergo, great grip and fits perfectly.

Well, just came back from oaks, what a waste of time. Vlad, thanks for the offer but pink isn't my color

Well, just came back from oaks, what a waste of time. Vlad, thanks for the offer but pink isn't my color

Pink is definitely my color, I LOVE pink.  just not on a rifle grip though 

Ok folks, next question what are the differences between an 18" SPR profile barrel and a 20" DMR profile barrel? Both are rifle length gas tubes, both .223 wylde, and both 1:8 twist.

For all practical purposes, two inches.

 

SPR is a designated sniper system, DMR is a squad marksman (non-sniper) system.  Besides the two inches, it's what the spec calls for optics and accessories to fit their respective combat roles.

For all practical purposes, two inches.

 

SPR is a designated sniper system, DMR is a squad marksman (non-sniper) system.  Besides the two inches, it's what the spec calls for optics and accessories to fit their respective combat roles.

Exactly.

 

While not a true sniper system, basically, its meant to extend the effective reach/range of the team or squad.

 

Each branch has their own version:

 

Army- DMR

Navy- SPR

Marines- SAMR

OK, so the profile designation being out of the way:

 

2 barrels, similar barrel profiles

 

.223 wylde

rifle gas system

.750 gas block

1:8 twist

same manufacturer and most likely same blank

 

18" vs 20", advantages/disadvantages? 

 

edit: I am aware of the weight disadvantage, the 20" weighs 7ozs more

One more thing.  While the US military typically uses the .223/5.56 cal in DMRs, the DRM designation is not caliber specific.  Many DMRs are chambered in .308 / 7.62.  The SPR is caliber specific though.

Eric wrote:

While not a true sniper system, basically, its meant to extend the effective reach/range of the team or squad.

 

 

If I recall correctly, the combat role is called "overwatch"  The role is intended to extend the reach of a unit, to pick off threats before the unit reaches an objective.  Also, as a counter sniper.

 

 

 

18" vs 20", advantages/disadvantages?

 

edit: I am aware of the weight disadvantage, the 20" weighs 7ozs more

 

I don't remember if you ever wrote what you want the rifle for, and at what distances you intend on shooting it. If you will only use it on a bench and you want to reach 800 yards then you need all the help you can get so although two inches will only add 75 fps IIRC you may as well do so. If you have any intention of carrying the rife, especially in the woods then those 75 fps don't seem so important. I think that more than a weight issue those extra two inches make it a little more unwieldy.

18", if you buy the right barrel with a proper gas systems for that length. .223 is .223 and those extra 2" of barrel will make no major difference. So why 18" instead if 16"? Because I always want rifle length gas systems, and you can't really make that work right on a 16" barrel. 

18" should do ya just fine..I have a Rainier Match 18 SPR with rifle gas system on my SPR build..and she's heavy as it is..save the weight..18" won't sacrifice much if anything

 

Sent from my SM-G920V using Tapatalk

Thanks guys, will go with 18"

One last thing worth mentioning.  1:8 is a popular "do all" twist good for bullets weighing 62gr up to 77gr but 77gr is really pushing the limits of the twist rate.  If you are building an SPR true to spec, then it should have a 1:7 twist.  1:8 is not milspec for a Mk12 SPR.  The only military rifle with a 1:8 twist, afaik is the SDM-R or squad designated marksman rifle, but that is a whole other animal.

 

The Mk12 was designed to shoot 77gr Mk262 ammo exclusively.  Remember, the SPR is a precision system so it was never intended to use M855 or M193, but, in a pinch you can shoot that ammo , just don't expect any decent accuracy from it.

 

From my 18" Middy 1:8 Rainier SS Match 223 Wylde barrel I get (at best) 2 MOA from 62gr M855 (which is fine by me, it's just cheap range fodder) and get sub moa using 69gr and 75gr OTM match ammo, which is not cheap range fodder. 

 

For all practical purposes, the technical differences don't really matter all that much, unless you have OCD like me.

Who cares really? I'm pretty sure the military spec comes with a giggle switch we can't have so at some point following a military spec becomes a waste of time for no good reason. Hell, does the spec still call for a old carbon fiber hand guard that was obsolete by 20 different better options?

 

The Mk12 was certainly not designed to ONLY use a single type of ammo, it surely prefers an ammo but it is not exclusive to it as that would be a dumb choice if it wasn't going to be good at using whatever else ammo was around. Heck, lots of M4's are also 1:7 and not exclusive to heavy ammo. 

Who cares really? I'm pretty sure the military spec comes with a giggle switch we can't have so at some point following a military spec becomes a waste of time for no good reason. Hell, does the spec still call for a old carbon fiber hand guard that was obsolete by 20 different better options?

 

The Mk12 was certainly not designed to ONLY use a single type of ammo, it surely prefers an ammo but it is not exclusive to it as that would be a dumb choice if it wasn't going to be good at using whatever else ammo was around. Heck, lots of M4's are also 1:7 and not exclusive to heavy ammo. 

 

Well....  On the 14.5" bbl and shorter M4s the 1:7 was to accommodate heavier bullets used to compensate for loss of velocity in shorter barrels.  They compensated with mass for lost velocity which meant longer bullets and a faster twist rate.

 

btw, the SPR and DMR do not have the giggle switch, they are strictly semi-auto.  They are using LaRue floated handguards now.

The "real" SPR's as far as I know have been placed on pretty much every lower type, for a long period they were just an upper to be applied to whatever lower. I think they eventually went to match trigger lowers, but the SPR thing isn't anywhere near as standardized and clear cut as sometimes made to be.

To add,  there are several versions of the MK12 SPR.

 

the original SPR was, indeed, just an upper receiver, hence Special Purpose Receiver.  It was attached to an M-16 lower, with A1 stock.  It had the PRI round, carbon fiber tube FF handguard.

 

The next version, the Mod 1, had a quad rail and collapsible stock, along with a better trigger.  I believe this is when "SPR" became "Special Purpose Rifle".

 

There was also a Mod H or Mod Holland version, but I dont believe the Mod H was actually deployed.  If it was, it was only in a small batch.

The reason i want the 1:8 is so i can shoot 55gr also

Wow. Some esoteric minutiae posted here.

 

OP, I think any quality barrel optimized for the load you want to shoot will work fine. A good trigger and some nice glass and you are on your way. Don't get hung up on the acronyms:

 

SPR is a rifle that meets a certain spec for the Navy and used in the DM role.

 

DMR is whatever rifle the squad DM uses. Could be an M14, an M16 variant like the SPR, a SCAR-H, a HK417, etc...

 

Both are used to effectively engage targets at intermediate distances - you don't need a trained sniper, but it's a little further than a rifleman with an M4 can handle effectively.

 

We are not face shooting haji (unfortunately) so terms like SPR/DMR are more for what distance you are planning to shoot than what the rifle actually looks like.

Wow is right. You make a crack about esoteric minutiae then.... you add to it, Rick, lol.

 

Wow. Some esoteric minutiae posted here.

 

OP, I think any quality barrel optimized for the load you want to shoot will work fine. A good trigger and some nice glass and you are on your way. Don't get hung up on the acronyms:

 

SPR is a rifle that meets a certain spec for the Navy and used in the DM role.

 

DMR is whatever rifle the squad DM uses. Could be an M14, an M16 variant like the SPR, a SCAR-H, a HK417, etc...

 

Both are used to effectively engage targets at intermediate distances - you don't need a trained sniper, but it's a little further than a rifleman with an M4 can handle effectively.

 

We are not face shooting haji (unfortunately) so terms like SPR/DMR are more for what distance you are planning to shoot than what the rifle actually looks like.

any thoughts on this barrel?

 

https://www.rainierarms.com/rainier-arms-223-wylde-barrel-spr-rifle-18-rock-creek-blank

Wow is right. You make a crack about esoteric minutiae then.... you add to it, Rick, lol.

 

 

What wasn't a crack. I love that shit!

it's funny when you talk SPR profile vs DMR profile since its whatever the company wants to call it.  Hell, I have an 18" noveske SPR and it uses an intermediate gas length

any thoughts on this barrel?

 

https://www.rainierarms.com/rainier-arms-223-wylde-barrel-spr-rifle-18-rock-creek-blank

I like it, it is pretty much my favorite combination, stainless, 18", rifle gas, 1:8, .223 wylde, accuracy guarantee. If the price is right for you, the barrel checks all the boxes.