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Nucleus Build Pictures

Im still running the 16# spring.
 
me 2. i had some issues at first last year, but i realized a big part was my primer seating depth. i was seating them too shallow. Deepened it, problem gone. i think the trigger pairing has a lot to do with it.
Yea.
trigger but as you mentioned I’m surprised how many seat primers shallow.
I just helped a guy with this last week.
 
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I experienced some light strikes initially in my Nucleus with a Timney 510 shooting 6BR with CCI450s...Josh @ PVA recommended degreasing the bolt/firing pin assembly and using a “U” sear from Timney (they sent it free) and that along with a couple hundred dry fires fixed my issue.

Very pleased with it so far.
 
I'm running the 16# spring yet, TT special, and have had a 2 rounds not firing in 1500rds. After talking with a guy who's been running one all year with federal ar srps and the 16# spring I wonder if the TT sear is a little too high and has a very slight amount of drag. He runs a bix and they recommend a low sear and he hasnt had any issues with his and those harder primers. I've been wanting to try running a 2 stage so have one on order with a low sear to tune it a little better. 2 non fires in 1500rds of factory ammo isn't a huge deal but of course they have come at matches on the clock lol.
 
16# spring with Timney trigger here, one light strike in about 1,000 rds, never cleaned the firing pin in fact I'm running it exactly as it came from ARC. It's one of the first 10 off the line for reference.
 
I had the 16# spring and TT diamond, ran perfect for around 350 rounds then would not fire 100% lite strikes . Disassembled cleaned no improvement. ARC replaced the spring with the 19# and I have not had a issue with 850 rounds since.

I was thinking the floating bolt head may be causing an issue it has .010 fore and aft play so it is under tension while cocked and when the striker is released the slop may be allowing the bolt body to move forward dampening the strike. Just a theory
 
I’m curious as to why some can run 16# trouble free(me included) and others have issues.
I went back to the 19# just for piece of mind.
I had mine lighting off cci450’s with the 16# spring no issues. The ones my 16# were sketchy were the rem 7.5 primers for some reason. They seem to be the toughest primers I had.
 
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I ordered the 19 pound spring for mine and I will get the occasional light strike if I don't keep the firing pin and spring clean. Now I run it dry just to avoid it collecting grime and it seems to work well, but I clean it every few hundred rounds, which is a PITA.

Ted has stated to keep the firing ping assembly totally dry. Lube will attract gunk and in low temperatures, will be more viscous. Did you set up the protrusion iaw Ted's drawings? The 1.335-1.345" from the top of the castlenut to the tip of the pin is apparently extremely crucial. I have mine around 1.337" iirc.
 

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giving the thread a bump- slowly working towards an ARC Nucleus build. I had ordered a JH from PVA but put the deposit towards a 6.5CM barrel. That will arrive Saturday.

I'm going to go with an MDT ACC chassis. I saw one in the thread, anyone else fit the Nucleus in an MDT ACC chassis and have any comments on fitment?

Also looking at different triggers. I'd like a 2 stage trigger, so looking at the Bix N Andy. TT isn't out yet (but might be by the time I actually need it), I have other Geissele triggers, did they fix the R700 trigger for use with the Nucleus?
Acc fits just fine
 

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So it looks like mine will be coming together sooner rather than later. Have an MDT ACC folder in its way, and found a lightly used Nucleus action with an 18" 308 barrel (I just got a 26" PVA 6.5cm barrel so will keep the 308 as a spare or use it for training). Has both 16# and 19# springs.

So the last part of the equation is a trigger. This will be my first r700 footprint rifle. I really like the Geissele SD-E trigger in my AR so wanted to go with a 2 stage trigger. Leaning towards the Bix N Andy as they seem to work very well with the Nucleus action (haven't heard of many BnA trigger users having light strikes) and get good reviews... anything else I should consider?

Sounds like Geissele has fixed their Super 700 trigger to work with the Nucleus, but leaning towards the BnA for the custom top sear fitting? Reading that the low sear seems to be the best for the Nucleus?

Now I need some magazines (will probably get MDT or ARC) and an action wrench and I'll be set. For now I"ll put a Burris XTRII 5-25 I have on the rifle, maybe upgrade the optics in the spring after I see what comes out at SHOT.

Sorry to clutter up the build pics thread with questions, but since y'all have the rifles and are using them, you are probably the best source of information for what works with the Nucleus actions!

And I'll post build pics after christmas when it all comes in. :)
 
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Those of you running MPA Chassis are you having to bed the recoil lug area? Are you using the Rem 700/cline footprint? Came across a You Tube review and the guy wasn’t too happy about having to bed the lug area. Probably got the wrong action footprint. My Nucleus should be here next week and I’ve narrowed it down between MPA Hybrid folder or a KRG W3.
 
Those of you running MPA Chassis are you having to bed the recoil lug area? Are you using the Rem 700/cline footprint? Came across a You Tube review and the guy wasn’t too happy about having to bed the lug area. Probably got the wrong action footprint. My Nucleus should be here next week and I’ve narrowed it down between MPA Hybrid folder or a KRG W3.
Why would you have to bed the lug? Did he do it because the lug lock doesn’t work with nucleus ?
 
I have no clue he doesn’t mention anything besides that he had a 700 footprint action and the lug didn’t fit like he wanted it to.
 
I don’t trust a thing from anyone who films with a fucking potato.
Who hangs their fucking TV on the wall longitudinally?
Edit: So he does articulate his issue fully. In order for the lug to make contact with the chassis, the holes don’t line up.
 
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Something is up with that MPA chassis inlet in that video for sure, the receiver bolts to recoil lug distance on the nucleus are standard Remington dimensions.

My nucleus dropped into a manners T4A with mini chassis, KRG whiskey 3, and an AX AICS perfectly.
 
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Mine fits my J Allen perfectly.
 
Did you send your actions to LRI? Or do they offer any prefit service? I’m looking to put a proof on mine and LRI seems like a good place to go.
LRI does nuke prefits
I’m contemplating having them do a shouldered prefit in 7SAUM soon.
 
@Emc_2015 pretty sure I bought your old 308 Nuke barreled action (just saw the photos on page 3 of this thread). I have a PVA 6.5CM shouldered prefit for it that I'll put on it soon but can't wait to take it out and shoot it. LRI sent me the specs on the barrel, might send downrange some 175SMK's and see how it likes those..

Put it in a MDT ACC chassis (the short barrel look a bit odd in the longer chassis) and a Timney 2 stage CE trigger. So far so good.
 
So this will be my first real foray into bolt guns, I owned a savage 10 for about a month... But I decided I wanted to build something worth shooting. So far I have a barreled action in hand and a few more parts on the way.

I went with PVA 308 marksman with barloc, went 308 to fill a role in certain competitions. Krg bravo for chassis and a trigger tech primary.

I will probably pick up ARC rings for my Bushnell XRS2, and I am up in the air on a muzzle device. Anyway, this should be a fun rifle when I get it all together.
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I am also using the 16# spring in my long action #64 made. Nothing else changed. I have Trigger Tech Diamond mounted with no problems yet. I did read the info ARC website about light strikes so I made sure I didn't have any lube or grease on the striker and measured the firing pin to make sure its out far enough. I really like this rifle/action. Got the shoulder prefit from LRI in 7 SAUM. I'll have to get a better picture tomorrow.

I only have 50 rounds through it but I'm already happy I went with a long action with the 7 SAUM because my last one was on a short action. It was a good shooter but being able to run these 183 SMK's all the way out is awesome!

This is my first KRG product and I'm really pleased with this chassis. I've had a few other chassis rifles but everything with this Whiskey 3 is right on. Very intuitive design, it just fits right. Nothing is awkward, everything is where it should be. I'm glad that I went with it, but maybe next time I'll get a folder.

ARC Nucleus Long action (From a Hide member here!)
TT Diamond Trigger flat bow (Not sure if I'm a fan yet:unsure:)
LRI K&P Shoulder prefit 7SAUM HV 27"
Impact Precision muzzle brake
KRG Whiskey 3 Gen 6
Vortex Gen2 Razor 4.5-27x56
Badger Ordnance USMC rings 1.00"
Atlas CAL bipod
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7 SAUM.jpg
 
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Well, so much for not buying another action. It's a good thing I'm single haha. This 1.1 will be replacing my Tikka varmint 223, possibly my 308 T3 CTR "general purpose rifle" as well. Current plan is a 20" bbl chambered in 223 rem, Whiskey 3 folder and eventually upgrading the PST II to something like an NX8 4-32 next year. Dealer only had the 0.535" and 0.473" options in stock so waiting on the 0.380" bolt head to be ordered in. I have to say, the 1.1 is noticeably nicer than my 1.0. There's a little less "clunkiness" during bolt closing, for lack of better term. Both have the 19lb springs. Haven't had any issues with light strikes on my 1.0. Keeping my fingers crossed for the 1.1.
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So I can finally post up a photo in the thread as my nucleus comes together...

A bit of background- newbie to precision shooting (but not shooting/reloading/etc) and wanted to get something nicer but didn't know too much about many of the customs on the market. Put money down on a PVA John Hancock late 2018. Waited. and a bit more waiting. And learning and reading. Fast forward to the end of 2019, used my deposit money on a PVA 26" 6.5 creedmoor barrel, cut rifled, black cerakote, etc. Picked up a new MDT ACC chassis. Was going to buy the Nucleus direct but right around that time I found a low round count nucleus barreled action on the hide built by LRI with an 18" 308 barrel. Couldn't pass up the opportunity to have both a 308 barrel and a 6.5CM barrel (I have a few rifles in 308 and a lot of brass). So the build began.

It looks a bit funny in it's current state because of the short 308 barrel, but the guys at MDT assured me no issues shooting it the way it is, and it'll look better when I put the 6.5 barrel on it I'm sure. To round it out, I picked up locally a Timney CE two stage trigger, and just received my MDT mags (2 12 round non backing plate metal) and a new Ckye-Pod with ARCA rail mount.

So current specs:
ARC Nucleus action (version 1.0)
LRI 308 fluted M24 cut rifled barrel finished @ 18" (barrel and action cerakoted gray)
PVA 6.5CM Marksman contour barrel, cut rifled, threaded and cerakoted black
Timney CE 2 stage trigger (will swap it one of these days for an Bix N Andy 2 stage)
MDT ACC chassis with folding stock
MDT Ckye Pod ARCA mounting

Currently have a Burris XTR II 5-25 mounted but have it for sale locally and will probably get an XTR III to put there instead.

Anyone have a spare Nucleus action wrench they want to part with???

Should go out next week and at least put a few rounds thru it and then will start to develop a load for the 308 (chambered for 168's, and of course I have a bunch of 175 SMKs).

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Lookin to replace the bolt knob w/ the A419 knob. Bolt in a vice, strap wrench, righty tighty/lefty loosey - anything I'm missing? Don't wanna bust off the handle or something
 
Lookin to replace the bolt knob w/ the A419 knob. Bolt in a vice, strap wrench, righty tighty/lefty loosey - anything I'm missing? Don't wanna bust off the handle or something

There's a good chance you might not even need a strap wrench. My handles on my 1.0 and 1.1 were only on hand tight.
 
Build took a new twist. Ended up dropping that 1.1 into my Bravo with my 6.5cm barrel and an AMG. The 1.1 bolt handle and knob hits the polymer side piece of the Whiskey 3 and I didn't feel like going at it with a Dremel. The 1.0 clears so that'll be used for my 223 rem folder build instead. Waiting on my barrel still but I'm supposed to recieve it in the next couple weeks pending any post office delays. Have new ARC high rings coming in on Monday as my existing MDT elites are too low with the thicker overmolded cheek piece.
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Finally finished my build!

nucleus action with a 20 inch proof sendero light chambered in .308. MDT LSS chassis and a Leupold VX-6 2-12 to top it off. Hats off to LRI for the amazing barrel work and cerakote! Going to be kind of a do all rifle for me, excited to see how it carries for whitetail in the Adirondack mountains this fall!
 

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Question for you guys with ARC Nucleus actions. My action is here but I won't be able to barrel it until Thursday due to work travel. I have a 6mm BR barrel & was wondering if anyone has used that caliber in a nucleus with either the MDT 6mm br mags or ARC mags with PVA kits installed for reliable feeding? EDIT!! I should have read all the threads as my question has been answered.

I have a McMillan A5 all decked out with Area419 acra rail & KMW bottom metal, Bix & Andy Tacsport pro trigger,
will be used in a couple NRL matches but mostly for priairie dog shooting.
 
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Question for you guys with ARC Nucleus actions. My action is here but I won't be able to barrel it until Thursday due to work travel. I have a 6mm BR barrel & was wondering if anyone has used that caliber in a nucleus with either the MDT 6mm br mags or ARC mags with PVA kits installed for reliable feeding? EDIT!! I should have read all the threads as my question has been answered.

I have a McMillan A5 all decked out with Area419 acra rail & KMW bottom metal, Bix & Andy Tacsport pro trigger,
will be used in a couple NRL matches but mostly for priairie dog shooting.
Seems you have your answer, but just to add to your confidence, I have since finished my BR build and running a PVA bbl, gen 1 Nuke, and MDT mags has had zero issues
 
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Question for you guys with ARC Nucleus actions. My action is here but I won't be able to barrel it until Thursday due to work travel. I have a 6mm BR barrel & was wondering if anyone has used that caliber in a nucleus with either the MDT 6mm br mags or ARC mags with PVA kits installed for reliable feeding? EDIT!! I should have read all the threads as my question has been answered.

I have a McMillan A5 all decked out with Area419 acra rail & KMW bottom metal, Bix & Andy Tacsport pro trigger,
will be used in a couple NRL matches but mostly for priairie dog shooting.
I had my Nucleus chambered in 6BR and I used both the MDT 6BR mags and ARC mags with no spacer kit installed. Both magazines worked quite well for me, though I usually preferred the standard ARC mags since they were more compact.

I've found that ARC mags work great to feed 6BR without a spacer kit, but they usually require tweaking unless you are using an ARC action. The ARC actions have always worked well with the ARC mags without any adjustment for me.
 
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since this thread is back near top- any of you running a Vortex Razor 4.5-27 on the nuke? what height rings (MDT ACC chassis if it matters) are you using? was assuming around 1" height but figured I'd see if I could verify so I can get some rings on the way before the scope gets here..
 
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since this thread is back near top- any of you running a Vortex Razor 4.5-27 on the nuke? what height rings (MDT ACC chassis if it matters) are you using? was assuming around 1" height but figured I'd see if I could verify so I can get some rings on the way before the scope gets here..


Here’s a nuke with an identical sized scope and medium ARC rings
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since this thread is back near top- any of you running a Vortex Razor 4.5-27 on the nuke? what height rings (MDT ACC chassis if it matters) are you using? was assuming around 1" height but figured I'd see if I could verify so I can get some rings on the way before the scope gets here..
Using a Spuhr 4001 - 1.18 with plenty of clearance.