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G38xOC
06-27-2012, 8:58 PM
My main goal was to save up and get an ar10 upper from JP rifles . as i was building one from their page to see how much it will cost , I found out their upper only compatible with their own lower ... looking..searching..continues .. ..

then , I found these uppers assemblies that will fit ( 4 diff company )

1.Fulton Armory
2.DPMS
3.Rock River
4.Model1sales

*if your me , what company would you chooose ?

I think JP barrels are really great barrels . all though i have no experience on any of them 5 companies I've mentioned . thats why , if I can build parts by parts , I can purchase the receiver ( one that works on lower ) , barrel ( JP ) , handgaurd , gas block , etc ... etc .. but my real concern is that , I have no tools and dont have any experience on putting upper together .

do you think , i should get the complete upper and be done with it . or if its even worth to invest on tools and other necessary items order to build it for just one time use ?

any help will be appreciated

thanks

1*mike
06-27-2012, 9:07 PM
I'm subscribing to this thread. I'm in the early stages of (intel gathering) of a 308 at build.

kemikalembalance
06-27-2012, 9:32 PM
All great companies, just did a transfer with model 1, they are about 2 to 3 months out...a month ago. "JD machining" seemed well built, but don't know the barrels. You can go to Rainier Arms (.com) and get the parts and build a damn good upper. Tool investment is not bad, but it depends on the for end you use. Between the brands, most are either DPMS or ARMALITE bolt patterns.

If you have the money, you can go with LaRue Tactical, but be ready to dump 3,000 to 3,500 and wait for 16 weeks.

When shopping, make sure to check the compatibility of the barrel nuts and lowers before buying. good luck dude

kemikalembalance
06-27-2012, 9:36 PM
http://www.rainierarms.com/?page=shop/browse&category=arvariants_receivers-upper

http://www.rainierarms.com/?page=shop/browse&category=arvariants_barrels_7.62mm/.308win

http://www.laruetactical.com/rifles

FMJBT
06-27-2012, 9:39 PM
What is your intended use for the rifle? (Hunting, Target, Long Range, etc.) And more importantly when dealing with large frame AR's: What is your budget for the build?

nimoZ
06-27-2012, 9:44 PM
My main goal was to save up and get an ar10 upper from JP rifles . as i was building one from their page to see how much it will cost , I found out their upper only compatible with their own lower ... looking..searching..continues .. ..

then , I found these uppers assemblies that will fit ( 4 diff company )

1.Fulton Armory
2.DPMS
3.Rock River
4.Model1sales

*if your me , what company would you chooose ?

I think JP barrels are really great barrels . all though i have no experience on any of them 5 companies I've mentioned . thats why , if I can build parts by parts , I can purchase the receiver ( one that works on lower ) , barrel ( JP ) , handgaurd , gas block , etc ... etc .. but my real concern is that , I have no tools and dont have any experience on putting upper together .

do you think , i should get the complete upper and be done with it . or if its even worth to invest on tools and other necessary items order to build it for just one time use ?

any help will be appreciated

thanks

I started with a matched pair upper/lower receiver. (KR7)
- Added a JP barrel, adjustable gasblock, forearm, low mass BCG
- Add a stock, buffer and spring.
- Lower parts kit depends on your lower. Many use AR15 lpk's.
- Charging handle

The only though part is the barrel nut. Just get the tool that is right for the forearm/nut you get. Then figure out how much to torque and how to measure that and hold the receiver.

Else, it's not very hard. Punch som pins and avoid scratching the receivers. Use painters tape to protect from scratches.

If you aren't used to tools, you may want to ask a smith for help.

Good luck with your project!

G38xOC
06-27-2012, 9:51 PM
What is your intended use for the rifle? (Hunting, Target, Long Range, etc.) And more importantly when dealing with large frame AR's: What is your budget for the build?


Im planing on using this rifle for long range target purpose . Im thinking around upto 2000 without scope

kemikalembalance
06-27-2012, 9:56 PM
Im planing on using this rifle for long range target purpose . Im thinking around upto 2000 without scope

From my building experience, you will have to piece it together to get a good barrel at that price it could be done though.
http://www.rainierarms.com/?page=shop/detail&product_id=2236

G38xOC
06-27-2012, 9:58 PM
I started with a matched pair upper/lower receiver. (KR7)
- Added a JP barrel, adjustable gasblock, forearm, low mass BCG
- Add a stock, buffer and spring.
- Lower parts kit depends on your lower. Many use AR15 lpk's.
- Charging handle

The only though part is the barrel nut. Just get the tool that is right for the forearm/nut you get. Then figure out how much to torque and how to measure that and hold the receiver.

Else, it's not very hard. Punch som pins and avoid scratching the receivers. Use painters tape to protect from scratches.

If you aren't used to tools, you may want to ask a smith for help.

Good luck with your project!

ty

I havent purchased the lower yet ( waiting on GB for for 80% still )
I might consider your route then , dont have to deal with miling out and plus I will for sure upper n lower will work .

from what i remember , JP barrel kit did come with low mass bcg , gas block . not sure about the gas tube though ( i will look into more )

if you mind , what JP barrel did you end up getting and how do you like it ?

G38xOC
06-27-2012, 10:04 PM
From my building experience, you will have to piece it together to get a good barrel at that price it could be done though.
http://www.rainierarms.com/?page=shop/detail&product_id=2236

Ty

once properly tighten the barrel to the receiver using barrel nut ranch and proper torque spec , am I pretty much done there as far as the barrel to the receiver goes ?

nimoZ
06-27-2012, 10:18 PM
ty

I havent purchased the lower yet ( waiting on GB for for 80% still )
I might consider your route then , dont have to deal with miling out and plus I will for sure upper n lower will work .

from what i remember , JP barrel kit did come with low mass bcg , gas block . not sure about the gas tube though ( i will look into more )

if you mind , what JP barrel did you end up getting and how do you like it ?

I got their 18" Light contour: 308-18L10-BT
- It works really well out to 900y, but a little longer would help for 1000y - depending on where you shoot.
At the time, I didn't want to make it too heavy.
I don't know how much weight the Medium 22" would add.

G38xOC
06-27-2012, 10:48 PM
^ one more question nimoz

which barrel nut did you use for the barrel

nimoZ
06-27-2012, 11:15 PM
^ one more question nimoz

which barrel nut did you use for the barrel

The one that came with the forarm/handguard (http://www.jprifles.com/1.4.4_hg_mod.php). Many have their own.

http://www.jprifles.com/photos_new/handguardnut.jpg

FMJBT
06-27-2012, 11:17 PM
Barrel nut selection will largely depend on what forend you end up using. Many come with their own barrel nuts.

G38xOC
06-28-2012, 9:08 AM
. Ill build this upper my self.It doesn't sound really technical if I have barrel nut wrench. I have a torque wrench too.
Ty u all,now I can move on doing home work on which barrel to go with for my liking range n get this project started

FMJBT
06-28-2012, 9:40 AM
A lot of people have had good luck with the DPMS 18" SASS barrel. I run one on one of my uppers, it's extremely accurate but a bit on the heavy side despite fluting. I'm currently running Rainier Arms 16" Select barrel on my newest upper, it's also a shooter. I've been really surprised with it's long range capabilities. Other barrels I'd suggest looking into:

Fulton Armory 18.5 stainless Criterion (Krieger)

Black Hole Weaponry 18" or 20" with rifle length gas system

Opening up an entirely new can of worms, once you go with a large frame AR a whole new spectrum of caliber choices opens up. 260 Remingon, 243, 6.5CM and 7mm-08 are just a few. Any of these will outperform the 308 at long range due to slimmer bullets with high BC #'s.

Out of the caibers based on the 308 Win cartridge, I'm really liking the 7mm-08. The 7mm bullets have insanely high Ballistic Coefficients, and can easily be driven at moderately high velocities that will make the best use of those high BC's while still retaining some decent barrel life.

Black Hole lists 7mm-08 as one of their standard chamberings.

captbilly
06-28-2012, 9:47 AM
Im planing on using this rifle for long range target purpose . Im thinking around upto 2000 without scope

You can do some serious target shooting with a .308 AR style rifle but 2000 (yards/meters?) isn't at all realistic. 1000 meters is about the limit for reliable long range shooting with any cartridge that a large frame AR will shoot, and even 1000 yards will take some careful ammo selection and good knowledge of ballistics. If you are talking 2000 feet then you should be able to do that with an AR-15, but again, 2000 yards is completely unrealistic for an LR 308 or AR-10. The is a company or two making super large frame ARs that will shoot .338 Lapua that will probably shoot 2000 meters with reasonable accuracy, but it is very very expensive.

Also where did you get the info that JP uppers aren't compatible with LR-308 style lowers? I just checked their site and they indicate that they are using the LR-308 style upper/lower.

FMJBT
06-28-2012, 10:10 AM
LOL, I'm pretty sure he meant $2000, not 2000 yards:D I thought the same thing the first time I read it too.

G38xOC
06-28-2012, 11:02 AM
Lol
Nimoz 18ich able to hit 900yards then, i was thinking about going with 20inch . Ill be happy with upto 1k yards if I can hit that far lol.

Ill have to search on some data n play with some loads later.


Jp complete rifle has one that can be used with dpms lower like ( I forgot which model, but I remember seeing one) but in description, it has modified to fit lower
ill try to copy n paste later

G38xOC
06-28-2012, 11:09 AM
http://www.jprifles.com/1.2.1_PSC_12.php

In spec, they talk about modified lower. I might be reading it wrong
I woulnt want to modifie anything to make it fit lol

Hoop
06-28-2012, 11:32 AM
I would buy a mega ma-ten monolithic upper lower and build off that. FWIW JP barrel kits are around 700 for barrel, bolt, gas block and brake.

nimoZ
06-28-2012, 12:27 PM
Opening up an entirely new can of worms, once you go with a large frame AR a whole new spectrum of caliber choices opens up. 260 Remingon, 243, 6.5CM and 7mm-08 are just a few. Any of these will outperform the 308 at long range due to slimmer bullets with high BC #'s.

Out of the caibers based on the 308 Win cartridge, I'm really liking the 7mm-08. The 7mm bullets have insanely high Ballistic Coefficients, and can easily be driven at moderately high velocities that will make the best use of those high BC's while still retaining some decent barrel life.

Black Hole lists 7mm-08 as one of their standard chamberings.
If I build another, I was going to look at .260. I don't know anything about 7mm-08, will need to look into that too. Thanks for the heads up!

http://www.jprifles.com/1.2.1_PSC_12.php

In spec, they talk about modified lower. I might be reading it wrong
I woulnt want to modifie anything to make it fit lol

I read it as fitting to a normal DPMS pattern lower or a modified JP LRP-07 lower, but I have no idea.

I would buy a mega ma-ten monolithic upper lower and build off that. FWIW JP barrel kits are around 700 for barrel, bolt, gas block and brake.

My preference would be a matched pair. Not sure about the monolithic just due to weight - I have not been able to compare them.


Lol
Nimoz 18ich able to hit 900yards then, i was thinking about going with 20inch . Ill be happy with upto 1k yards if I can hit that far lol.

The problem is that it's not a linear equation, the drop-off from 900 to 1,000 is substantially more than from 800 to 900. But all things equal, a 20" will do it better than a 18".
- I even tried mine out to 1,200y, but I might as well have been trowing rocks then :)

FMJBT
06-28-2012, 1:01 PM
If I build another, I was going to look at .260. I don't know anything about 7mm-08, will need to look into that too. Thanks for the heads up!

The problem is that it's not a linear equation, the drop-off from 900 to 1,000 is substantially more than from 800 to 900. But all things equal, a 20" will do it better than a 18".
- I even tried mine out to 1,200y, but I might as well have been trowing rocks then :)


Another reason I've been considering a 7mm-08 build is that 308 brass can be formed into 7mm-08 brass just by running it through a full length sizing die. Going much smaller than 7mm from a 308 case often requires extra operations like neck turning to get the brass to the proper size/thickness.

I've been shooting my new 16" upper out to 1000 using 190 SMKs and Nosler CCs. It's definitely not the ideal setup for getting out that far, but it does it pretty well. Surprisingly it seems to be about as consistent at that range as my 26" Savage 10FP 308 is. I kind of stumbled on this combination by accident, if I had intentionally built it for getting to 1000, I would have gone with a 20" barrel for the extra velocity.

G38xOC
06-28-2012, 3:00 PM
I would buy a mega ma-ten monolithic upper lower and build off that. FWIW JP barrel kits are around 700 for barrel, bolt, gas block and brake.

Those style looks bad*****. My question is that style would be .. how to install a barrel sinxe receiver and handguard is in one unit

Hoop
06-28-2012, 4:06 PM
Read the fine print. It comes with a special wrench.

Jpach
06-29-2012, 10:03 AM
Another reason I've been considering a 7mm-08 build is that 308 brass can be formed into 7mm-08 brass just by running it through a full length sizing die. Going much smaller than 7mm from a 308 case often requires extra operations like neck turning to get the brass to the proper size/thickness.

I've been shooting my new 16" upper out to 1000 using 190 SMKs and Nosler CCs. It's definitely not the ideal setup for getting out that far, but it does it pretty well. Surprisingly it seems to be about as consistent at that range as my 26" Savage 10FP 308 is. I kind of stumbled on this combination by accident, if I had intentionally built it for getting to 1000, I would have gone with a 20" barrel for the extra velocity.

Yes, 7mm-08 is ****ing sick. I was actually building a 7-08, the only reason why I didn't is because the LMT MWS came out and I found it for about 600 below what they typically go for.

The 7-08 can be pushed to pretty decent velocities out of shorter barrels. I forget who I talked to (it might have been GAP), but allegedly the 7-08 is a pain in the *** in the AR platform. I would imagine that with an adjustable gas block, it'd work just fine.

FMJBT
06-29-2012, 8:43 PM
Yes, 7mm-08 is ****ing sick. I was actually building a 7-08, the only reason why I didn't is because the LMT MWS came out and I found it for about 600 below what they typically go for.

The 7-08 can be pushed to pretty decent velocities out of shorter barrels. I forget who I talked to (it might have been GAP), but allegedly the 7-08 is a pain in the *** in the AR platform. I would imagine that with an adjustable gas block, it'd work just fine.

Was it an issue with being over-gassed? I could definitely see that with a round like the 7-08, especially with heavier bullets. I'd probably opt for an 18" barrel with rifle length gas system along with an adjustable gas block after seeing how my 308's run with 16" and 18" mid length systems. Both of them are definitely running into over-gassed territory, surprisingly the 16" barrel more so than the 18" one. Recoil on the Rainier Arms barrel is STOUT. It's the only rifle I've ever had to actually lock-tite all the scope mounting bolts on. I'm thinking an adjustable gas block and probably a heavier buffer from Slash are in this guns future.

Note to the OP: Get the adjustable gas block to start out with. it may be more expensive initially, but the bennefit of being able to tune your rifle for optimum function and minimal recoil is worth it. I've had to build 3 of these things now before I figured that out :o

G38xOC
06-29-2012, 10:28 PM
Was it an issue with being over-gassed? I could definitely see that with a round like the 7-08, especially with heavier bullets. I'd probably opt for an 18" barrel with rifle length gas system along with an adjustable gas block after seeing how my 308's run with 16" and 18" mid length systems. Both of them are definitely running into over-gassed territory, surprisingly the 16" barrel more so than the 18" one. Recoil on the Rainier Arms barrel is STOUT. It's the only rifle I've ever had to actually lock-tite all the scope mounting bolts on. I'm thinking an adjustable gas block and probably a heavier buffer from Slash are in this guns future.

Note to the OP: Get the adjustable gas block to start out with. it may be more expensive initially, but the bennefit of being able to tune your rifle for optimum function and minimal recoil is worth it. I've had to build 3 of these things now before I figured that out :o

ty , I was planing on getting rifle length gas block due to heard and many stated that rifle length would be better . but if i getting a adjustable block would make the rifle for better operation , I will forsure look into that .

hcbr
06-29-2012, 10:55 PM
I temporarily chose the dpms because it was the cheaper solution. I'm waiting for the LAR Grizzly 7.62 side charging uppers they'll be releasing hopefully before the end of this year.

Jpach
06-29-2012, 11:50 PM
Was it an issue with being over-gassed? I could definitely see that with a round like the 7-08, especially with heavier bullets. I'd probably opt for an 18" barrel with rifle length gas system along with an adjustable gas block after seeing how my 308's run with 16" and 18" mid length systems. Both of them are definitely running into over-gassed territory, surprisingly the 16" barrel more so than the 18" one. Recoil on the Rainier Arms barrel is STOUT. It's the only rifle I've ever had to actually lock-tite all the scope mounting bolts on. I'm thinking an adjustable gas block and probably a heavier buffer from Slash are in this guns future.

Note to the OP: Get the adjustable gas block to start out with. it may be more expensive initially, but the bennefit of being able to tune your rifle for optimum function and minimal recoil is worth it. I've had to build 3 of these things now before I figured that out :o

Wait a minute.....I made a mistake. I am almost positive that GAP told me that 260 is a pain in the *** in a semi that is less than 20" or so. My bad!

I am now inspired to have a 7-08 barrel made for my LMT just for the sake of launching those sexy high BC 162 AMAXs.

It'd be cool to install an adjustable gb on my LMT. Maybe I can mod it myself?

G38xOC
06-30-2012, 8:36 PM
is checking headspace hard ? any needed tools for this task ?

I was looking at fulton sidecharger receiver along with their BCG and wanted to install JP barrel . JP web describes this ( All barrels also include a JP EnhancedBolt™ individually head-spaced to the barrel for flawless fit and function )

since their barrel is head-spaced check with bolt , do i still need to worry about head-spacing due to different upper receiver ?

FMJBT
06-30-2012, 9:08 PM
is checking headspace hard ? any needed tools for this task ?

I was looking at fulton sidecharger receiver along with their BCG and wanted to install JP barrel . JP web describes this ( All barrels also include a JP EnhancedBolt™ individually head-spaced to the barrel for flawless fit and function )

since their barrel is head-spaced check with bolt , do i still need to worry about head-spacing due to different upper receiver ?

With a matched bolt/barrel combo like the one from JP you won't have to worry about headspace.

ahren111
07-01-2012, 6:13 AM
I would buy a mega ma-ten monolithic upper lower and build off that. FWIW JP barrel kits are around 700 for barrel, bolt, gas block and brake.

:iagree:

The Mega sets are very nice! I'm really happy with mine.

FMJBT
07-01-2012, 11:54 AM
I am now inspired to have a 7-08 barrel made for my LMT just for the sake of launching those sexy high BC 162 AMAXs.

It'd be cool to install an adjustable gb on my LMT. Maybe I can mod it myself?

Might be able to install one of these:

http://www.midwayusa.com/product/363956/syrac-ordnance-click-adjustable-gas-block-ar-15-lr-308-standard-barrel-0750-inside-diameter-low-profile-steel-matte

They make a clamp version too, if the MWS barrel isn't dimpled for set screw gas blocks. The gas tube on the MWS barrels looks slightly different than a regular gas tube, straight instead of contoured along the barrel Not sure if a regular gas tube would work or not, you might have to swap the tube out of the existing MWS gas block. Your MWS looks F'ing sick BTW :chris:

G38xOC
07-01-2012, 12:14 PM
just did a Dro on TM10 and picked up a UBR stock and 1 10/20 pmag . thats all i can afford now . It going to be a safequeen for while . but thanks to all for the help

yea .. them Pmag man ... thing is beefy