1st build is being a test of patience...

[Chippewa]

Hello,
I have sloooowly been getting components,which most were ordered last May thru June. Hoping to put together this LR308 in 308win real soon. Once barrel arrives in next couple of days i'll be able to mount up for a picture.

JMT carbon50 lower reciever
Juggernaut Grey upper reciever
Juggernaut charging handle
Magpul PRS Stock Grey
AR Stoner h-duty rifle length buffer tube
CMMG "custom lpk"
Triggertech AR10 comp 3.5# trigger
JP Enterprise:
* Supermatched 20in barrel &
headspaced enhanced bolt.
*Adjustable 2peice gas block
*LMOS bolt carrier
*Silent Capture Gen2 H2 buffer
Magpul grip in Grey
Smoke carbon 15" handgaurd(w/ rail)
Strike Ind. Comp King brake/flash hide

Thinking hard on NV scope like Pulsar digiscope an replace brake for a suppressor. Was told the new e-file for suppressors should speed up purchasing to 30days. Hope that can happen.

So with 125g sst for coyote and larger longer bullets for paper is my goal here day or night.

Thanks for any thoughts.

 

[_Windrider_]

Hello,
I have sloooowly been getting components,which most were ordered last May thru June. Hoping to put together this LR308 in 308win real soon. Once barrel arrives in next couple of days i'll be able to mount up for a picture.

JMT carbon50 lower reciever
Juggernaut Grey upper reciever
Juggernaut charging handle
Magpul PRS Stock Grey
AR Stoner h-duty rifle length buffer tube
CMMG "custom lpk"
Triggertech AR10 comp 3.5# trigger
JP Enterprise:
* Supermatched 20in barrel &
headspaced enhanced bolt.
*Adjustable 2peice gas block
*LMOS bolt carrier
*Silent Capture Gen2 H2 buffer
Magpul grip in Grey
Smoke carbon 15" handgaurd(w/ rail)
Strike Ind. Comp King brake/flash hide

Thinking hard on NV scope like Pulsar digiscope an replace brake for a suppressor. Was told the new e-file for suppressors should speed up purchasing to 30days. Hope that can happen.

So with 125g sst for coyote and larger longer bullets for paper is my goal here day or night.

Thanks for any thoughts.

30 days? Be lucky if it’s 90 days.

 

[Vivacious Stallion]

You didn't really ask any questions, so is this just asking people to roast your parts crate? Looks fine I guess?

I haven't heard anyone claim the efile will be 30 days. I heard more like "optimistically" several months, down from 9 months to a year.

 

[msgriff]

Even though it may all say "DPMS", mixing lower and upper manufacturers is a gamble, especially with a 80%. Same with LPKs.
Be aware of the difference between DPMS "high" and "low". I don't know if your upper and handguard are compatible or if it's applicable.
That barrel has a 0.936 gas journal. That 2 piece AGB won't fit under all rails, no idea about the Smoke.
Some ambi charging handles will hit the cheek riser on a PRS Gen 3 (and Lite) stock. Don't know if the Juggernaut is one of them.
That JP Silent Capture might be an issue, it will probably need a custom spacer or cut down the supplied one. I would contact JP for advice.
Low mass actions can be a pain to tune, especially when using a large range of bullet weights. Good luck with the build.

 

[Vivacious Stallion]

Even though it may all say "DPMS", mixing lower and upper manufacturers is a gamble, especially with a 80%. Same with LPKs.
Be aware of the difference between DPMS "high" and "low". I don't know if your upper and handguard are compatible or if it's applicable.
That barrel has a 0.936 gas journal. That 2 piece AGB won't fit under all rails, no idea about the Smoke.
Some ambi charging handles will hit the cheek riser on a PRS Gen 3 (and Lite) stock. Don't know if the Juggernaut is one of them.
That JP Silent Capture might be an issue, it will probably need a custom spacer or cut down the supplied one. I would contact JP for advice.
Low mass actions can be a pain to tune, especially when using a large range of bullet weights. Good luck with the build.

My dad built an AR10 from various manufacturers without researching much first and that had all sort of issues. I finally got it unfucked over Xmas. Personally, I'm glad I bought my LMT as my first 308 AR instead of building. I don't think some people understand that ar10s are not standardized like ar15s and they just dive in.

 

[Chippewa]

Thanks guys. I was really just looking for educated eyes to see what I was trying piece together. And have your experience catch the the little things I haven't been able to find on the net. Just waiting for the barrel this long is starting to feel like waiting thru the calm before the storm trying to tune it. So far the project has been going really smooth even. Trigger even fits great.

I'll look at the cheek riser issue though.

One question. Are the lug lock barrel vise tools the way everyone goes instead of the reciever block types. Double the cost for a rare use tool but kind of makes sense looking at them. I don't know. Or 30 bucks for barrel install at local shop.

 

[msgriff]

snip....

One question. Are the lug lock barrel vise tools the way everyone goes instead of the reciever block types. Double the cost for a rare use tool but kind of makes sense looking at them. I don't know. Or 30 bucks for barrel install at local shop.

The only reaction rod that worth it is a MI 308URR. Here's what I use, muzzle devices on the right, barrel nuts on the left. Sandwich the upper between the vise jaws, don't stand it up.

 

[Chippewa]

So you use barrel vis for brake installs and the receiver blocks for barrel installs? I made oak barrel jaws an could use them same way

 

[_Windrider_]

Thanks guys. I was really just looking for educated eyes to see what I was trying piece together. And have your experience catch the the little things I haven't been able to find on the net. Just waiting for the barrel this long is starting to feel like waiting thru the calm before the storm trying to tune it. So far the project has been going really smooth even. Trigger even fits great.

I'll look at the cheek riser issue though.

One question. Are the lug lock barrel vise tools the way everyone goes instead of the reciever block types. Double the cost for a rare use tool but kind of makes sense looking at them. I don't know. Or 30 bucks for barrel install at local shop.

I use reaction rods for AR’s

 

[r.tenorio671]

....for AR's (both 15 & 10's) I would recommend using a "reaction rod" type over any clamp type of fixture. The rod types interface with the barrel extension and prevent any kind of "load" being placed on the receiver when the barrel nut is tightened down. When installing a muzzle device, it also prevents any load being applied to the pin on the barrel extension that fits into the slot of the receiver face, preventing the pin from applying force to the one side of the alignment slot as the muzzle device is installed or removed. The torque values required for a barrel nut or muzzle device will NEVER exceed the torque values required for the barrel extension so extremely unlikely to loosen a barrel extension....not impossible, but that would mean the barrel extension was installed incorrectly or the "nut" handling the wrench was inappropriate.

...pricing between rod types is comparable. The Magpul BEV Block is an alternative and works on the same principal, interfaces with the barrels extension at a lower cost. BEV Block comparable to pricing for clamp type blocks. Clamp type blocks may not fit alltypes of receivers, i.e., proprietary designs, billets, etc.

 

[2aBaC̶a̶]

Real Avid makes an inexpensive reaction rod and mag block and other tools.
Odinworks makes a decent vise block.
Those 3 are about the only jig type tools I use.

I have to ask why not match a JT lower?

 

[Chippewa]

Just order the MI308URR. $77 on OpticsPlanet with 2 day shipping. Didn't realize I had so many "Bucks" built up with them.
An I guess I went carbon for ease milling for a first go at this.

 

[2aBaC̶a̶]

As long as it goes bang reliably and accurately and you're happy with it, thats all that really matters. Some good parts in there, lets hope they all play nice together.

 

[Chippewa]

Another question to ponder. Shots being probly 800yrds max day time an half that at night, you have any suggestions on worth of NV vs Thermal vs "the heck with it" an get a Night Force NX8 with spot/flood set up on coyotes. Nervous to buy electronic scope really, but if up front fun outways its worth long term maybe its worth it.
Also load work up with a silencer will be a first. I assume it a balancing act between db increase with powder burnt. I have some loads for bolt guns hoping could just try with this one an tune gas block to run. Or just buy ammo for this rifle?
(125g sst h4895 at 3000fps)
(150g boattail speers h4895 2700fps)
(178g eldx cfe223 2550fps)
My barrel ordered is 1-10twist but at this point the newer 1-11 may show up... I would think these bullets will fly pretty good either way.
Thanks for any help

 

[Chippewa]

This JT charge handle is inline for sure to hit check riser. Better look up stroke length. Thanks for heads up on this.

 

[2aBaC̶a̶]

Pretty sure the PRS stock is designed so that the charging handle wont hit the cheek rest.

View attachment 7797243
This JT charge handle is inline for sure to hit check riser. Better look up stroke length. Thanks for heads up on this.

 

[rpoL98]

is that a plastic lower? My opinion and that's all it is, I think you need a lot of beef where the buffer tube is mounted, more so than an AR-15. that kick-up needs to be really beefy to absorb 308-level recoil with flexing. Buttstock mounted on the buffer tube imparts a lot of leverage at that junction.

 

[Chippewa]

Its made by James Madison Tactical. They call it the Carbon50. I went with this one because of comparisons done with others. This one has upgrades in areas of stress. We shall see. It really was nice material to work with as far as milling on a standard drill press and a x-y base clamp. The material cuts clean which seemed to indicate real good density of resins around fibers.
Hopefully nothing cracks. I'll be sure keep fire counts vs durability findings. Id like to make more off these if it works out. Like an all SMOKE stock/handgaurd/grip with carbon barrel.

 

[hlee]

30 days? Be lucky if it’s 90 days.

Shit, my paperwork hasn’t been submitted yet, going on 70 days…

 

[msgriff]

is that a plastic lower? My opinion and that's all it is, I think you need a lot of beef where the buffer tube is mounted, more so than an AR-15. that kick-up needs to be really beefy to absorb 308-level recoil with flexing. Buttstock mounted on the buffer tube imparts a lot of leverage at that junction.

Putting one of the heaviest stocks available on it isn't going to help. Composite lowers might be better suited for lightweight stocks, like a SuperStoc at 25% the weight of a PRS Gen3.

 

[2aBaC̶a̶]

Its his first rifle.

 

[Chippewa]

Thanks for earlier feedback. Hopefully when I finally get this thing together no issues like the ones I have been dealing with getting parts.
So I gave up on USPS an asked the site I ordered from for options. They sent a second barrel by good old UPS an had it in 3 days since they have some instock. I thought awesome, but come to find the barrel machining at the journal is smaller than advertised. What the hell. Now waiting to hear from JP.
Maybe i'm not understanding some thing with this dimension. I just want to find out is this difference intended or oopsed and does it affect this 20" super match 308win barrel. Advertising shows spec for .936" for what I thought blocks like JPGS-8 would be designed for which I bought last May for this project. Except this newer 11twist barrel is milled down to a .875" spec. Nearly flattened to the forward contour.

You think it really matters since thier shorter thinner barrels are at .75". So annoying. Any advice on this would be great. And I have a feeling i'll have a new in box JPGS-8 to sell maybe.
Thanks

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[acudaowner]

but so worth it will it be when you get it all together and are able to take it to the range and on the first round down the tube jam what no it should be bang but next round jam let the cursing commence as your blood boils into a form new form of hot magma behind your eyes steam is visible for all to see . No I jest I hope it goes off with out a hitch and it's everything you hoped it will be .

 

[2aBaC̶a̶]

Thanks for earlier feedback. Hopefully when I finally get this thing together no issues like the ones I have been dealing with getting parts.
So I gave up on USPS an asked the site I ordered from for options. They sent a second barrel by good old UPS an had it in 3 days since they have some instock. I thought awesome, but come to find the barrel machining at the journal is smaller than advertised. What the hell. Now waiting to hear from JP.
Maybe i'm not understanding some thing with this dimension. I just want to find out is this difference intended or oopsed and does it affect this 20" super match 308win barrel. Advertising shows spec for .936" for what I thought blocks like JPGS-8 would be designed for which I bought last May for this project. Except this newer 11twist barrel is milled down to a .875" spec. Nearly flattened to the forward contour.

You think it really matters since thier shorter thinner barrels are at .75". So annoying. Any advice on this would be great. And I have a feeling i'll have a new in box JPGS-8 to sell maybe.
Thanks

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What part is wrong?

Caliber: .308 Win.
Length: 20"
Gas System: Rifle-length
Twist: 1:11.25 button rifled
Contour: .750 under hand guard/.875 in front of gas block
Diameter at Gas Block: .936
Muzzle Threads: 5/8"-24 TPI
Material: 416R Stainless
Bolt Assembly: High Pressure JP EnhancedBolt™
Weight: 47.6 oz.

 

[Chippewa]

Where gas block diameter should be .936" its cut to .875". Just sucks because I have the larger block for it ready to go. I'm just antsy at this point.

 

[2aBaC̶a̶]

Well that's some BS. I would be contacting them to exchange the one of the two.

 

[Chippewa]

So got confirmation the 2022 20" Suppermatch 308 barrel's gas journal specs were dropped to .875" due to parts consolidation. They haven't updated the website yet. So I ordered a new gas block. The quality better out way the b.s. so far.

 

[Chippewa]

This first rifle project is so slowly coming together. Monday the new scope an BCG pins are supposed to be on my doorstep. Crossing my fingers.

Also thanks for the advice on the MI rod. Felt very secure and proper getting everything torqued.