Nucleus Light Primer Strikes

Triple D

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I’m 2 matches in with mine. The first match, I fired 0 rounds. That weekend SUCKED. In the last match, I had 9rds that didn’t fire. This was after I stripped the bolt of all of the grease that came from the factory in locations that it shouldn’t have been. I received the 25lb springs the day that I got back from the last match, but I haven’t installed them yet.

I hope to get this issue resolved, but I’m done with revolutionary new designs and pre-orders. Any money I potentially saved by not getting more Deviants has been lost in match and travel costs anyways.
 

Darkhorse1

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I’m 2 matches in with mine. The first match, I fired 0 rounds. That weekend SUCKED. In the last match, I had 9rds that didn’t fire. This was after I stripped the bolt of all of the grease that came from the factory in locations that it shouldn’t have been. I received the 25lb springs the day that I got back from the last match, but I haven’t installed them yet.

I hope to get this issue resolved, but I’m done with revolutionary new designs and pre-orders. Any money I potentially saved by not getting more Deviants has been lost in match and travel costs anyways.
I’m kind of the same opinion. I love the action so far (literally no complaints except mine craters sr primers but they are consistent regardless of charge so I think it’s “normal”) and the pre-sale price was a ridiculous value imo, but the possibility of malfunction doesn’t leave me warm and fuzzy from a reliability standpoint. Not to beat a dead horse, but offering a different spring as a resolution and not doing a recall is odd to me.
 
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NWnewguy

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Yep, it pretty much seems like it. This is my first custom action too, and I'm nervous about getting light strikes already and I haven't even shot it. If you call, they should ship out a spring to you.

ARC's customer service leaves something to be desired, but Ted says they'll be working very hard to improve that this year. Hopefully they do. I like their designs, but they struggle on the follow through a lot recently. Nucleus, Barloc, ARC mags. Hell, the Mausingfield took like three revisions after it was released to get it to what it is now.

Ive been following this thread with interest due to owning two Nukes and although I've had no problems with them, I'm hoping for the sake of all the customers as well as ARC that they figure out what the real issue is and fix it for everyone. As far as a recall; generally recalls are for safety issues. If you have had problems, or just want to be sure you don't have issues at a match or whatever, give them a call and they will send you a new spring. I definitely agree that this issue could be handled better. As evidence, read through this thread and the fact that it's been going since the actions basically started shipping and it's still not really resolved.

However the real reason I'm posting is to say that I have one of the first 15 Mausingfield actions sold and it's my favorite (of four) one. It's still in the raw and I've never had any corrosion issues and it just feels amazing. So while I would agree with the MF, they did some tweaks, but in my opinion and I think just about anyone who has cycled and shot one of the originals, they were real good right from the start.
 

miles13242

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I’m kind of the same opinion. I love the action so far (literally no complaints except mine craters sr primers but they are consistent regardless of charge so I think it’s “normal”) and the pre-sale price was a ridiculous value imo, but the possibility of malfunction doesn’t leave me warm and fuzzy from a reliability standpoint. Not to beat a dead horse, but offering a different spring as a resolution and not doing a recall is odd to me.
I don't think they want to say anything is wrong with the spring. I know in another thread Ted mentioned that in the actions they received from customers that were experiencing light strikes, that it was user error. That's why I was hoping for a more detailed reassembly video, more so than the sub 5 minute disassembly video where he's at a concrete shooting bench. If it is indeed user error, I would like to see where people go wrong so I don't make the same mistake.
 

MarkLeupold

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Alright, the results are in! Shout out to @Kiba for getting me some numbers I needed to complete the Firing Pin Impact Studies whitepaper calculations.

Remington 700 LANucleus 16#Nucleus 19#Nucleus 25#Accuracy International
Effective Striker Weight1016.4 gr931.65 gr931.65 gr931.65 gr902.8 gr
Average Spring Force22 pounds16.5 pounds19.6 pounds25.8 pounds25.5 pounds
Potential Energy97 in-oz69.17 in-oz82.16 in-oz108.15 in-oz98.74 in-oz
Average Acceleration151.5 g's125.1 g's148.6 g's195.6 g's198.1 g's
Impact Velocity15 ft/sec13.2 ft/sec14.4 ft/sec16.6 ft/sec16.0 ft/sec
Lock Time3.07 ms3.3 ms3.0 ms2.6 ms2.5 ms
Impact Momentum1.083 oz-sec.8656 oz-sec.944 oz-sec1.088 oz-sec1.024 oz-sec
Average Impulse Force162 lbs for 417 microseconds138 lbs for 391 microseconds164 lbs for 359 microseconds218 lbs for 311 microseconds198 lbs for 323 microseconds

(This table is probably going to look like crap on mobile)

Personally, I think this paper could have been improved in its math notation, but I was able to stumble through it after some thinking. Nevertheless, it got the job done.

(An interesting side note: the calculations take the entire dry-fire striker travel into account (.275" on the M700, .262" on my Nucleus, and .242" on the AI) and not the striker travel to the action face where we assume the striker would impact the primer and begin slowing down.)

I also calculated for the 16# and 25# Nucleus springs, as well as Kiba's AI to see what's going on as spring weight increases and to give us something very reliable to compare to. I included the calculations for an M700 LA for another comparison.

The first thing I notice is that the effective striker weight of the Nuke is heavier. That much we already knew. Potential energy seems anemic, as that is contributed by the spring force. Low spring force = low energy; seems intuitive.

Acceleration and velocity are low as they are related to force and mass. Low force, high mass, low speed/acceleration. Same with lock time.

Interesting note comes in at momentum. The Tubb SpeedLock comes in at a .828 oz-second momentum (not included on chart), which Tubb seems to brag on. The low-mass striker will "not be as likely to set back the case shoulders...or to reseat a jam-seated bullet deeper into the thinned case neck in a firing benchrest competition rifle." I don't think this concern would apply to practical rifle shooters, but whatever. He also praises the low-mass striker (low momentum) for reducing pre-ignition vibrations, reducing the "terminal momentum dump" of the striker impacting the primer, and the reduced lock time (to 2.16 milliseconds).

In the average impulse force, I believe we find something we've been looking for. This, to me, seems like the kind of measure that will show if a rifle will consistently set off a primer. I think the M700 LA will consistently set off primers (at least large rifle), and the 19# Nucleus provides about the same force over a shorter period. The 25# Nucleus compares closer to the ultra-reliable (even on CCI No.450's according to Kiba) Accuracy International. This seems to be due to the heavy striker spring and the lighter striker weight.

Happy to run more numbers for more comparisons if someone is willing to feed me the data.

EDIT: I just noticed that the paper was written by Mr. @Jim Boatright (if this is the same Boatright), maybe he can provide some insight and analysis into this as well.
 
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MarkLeupold

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The Impact momentum of the 25# Nucleus VS The Accuracy International, Nucleus is faster and heaver yet the AI is higher. is that correct?
It was late, don't really know where I pulled that momentum from. I'll update the table with the correct numbers. Good catch!!
 

Sierra770

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So if I'm reading this correctly, we are gonna have to deal with the heavier bolt lift of the #25 spring, I feel we want the reliability of an AI.
 

ThePretzel

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So if I'm reading this correctly, we are gonna have to deal with the heavier bolt lift of the #25 spring, I feel we want the reliability of an AI.
One important thing to note about this statement is that the 25 pound spring is likely to have a lighter bolt lift than the AI does, even though it's going to be heavier than the stock Nucleus spring.

The Nucleus has 72 degrees of cocking cams, compared to the 60 degrees of cocking cams on the AI. The nearly identical spring (only .3 pounds heavier) is being compressed a nearly identical distance (only 20 thousandths) but the work required to complete this spring compression is spread out over 12 more degrees of rotation. Unless the AI has a longer bolt handle, significantly less friction, or is breaking the laws of physics the bolt lift on it will still be heavier than the bolt lift on a Nucleus with the 25 pound spring.

Big thanks to @MarkLeupold though for crunching the numbers on the different springs, it's definitely helpful when it comes to visualizing the differences between the Nucleus spring options and other common actions on the market today.
 

Kiba

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One important thing to note about this statement is that the 25 pound spring is likely to have a lighter bolt lift than the AI does, even though it's going to be heavier than the stock Nucleus spring.

The Nucleus has 72 degrees of cocking cams, compared to the 60 degrees of cocking cams on the AI. The nearly identical spring (only .3 pounds heavier) is being compressed a nearly identical distance (only 20 thousandths) but the work required to complete this spring compression is spread out over 12 more degrees of rotation. Unless the AI has a longer bolt handle, significantly less friction, or is breaking the laws of physics the bolt lift on it will still be heavier than the bolt lift on a Nucleus with the 25 pound spring.

Big thanks to @MarkLeupold though for crunching the numbers on the different springs, it's definitely helpful when it comes to visualizing the differences between the Nucleus spring options and other common actions on the market today.
The nucleus will still probably have the heavier bolt lift even with the same spring rate as the AI because AI and ARC took different approaches to the cocking method.

Even though the AI has what I measured to be an approximately 25.5# average firing pin spring force, and the AI bolt lift is only 60 degrees rotation, it doesn't feel quite that heavy on bolt open because the AI is approximately a 70/30 action (70% cock on open, 30% cock on close.)

With a 25# spring in the Nucleus, it's probably going to feel heavier on bolt opening than the AI... because while the Nucleus has 12 degrees more of bolt rotation over which to spread the cocking of the firing pin (72 vs 60 degrees) which will help with the lift effort, the Nucleus is a 100% cock on open action (with maybe an additional 5% overcocking on close depending on your trigger) so all the compression of the firing pin spring happens on bolt open.
 
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MarkLeupold

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The nucleus will still probably have the heavier bolt lift even with the same spring rate as the AI because AI and ARC took different approaches to the cocking method.

Even though the AI has what I measured to be an approximately 25.5# average firing pin spring force, and the AI bolt lift is only 60 degrees rotation, it doesn't feel quite that heavy on bolt open because the AI is approximately a 70/30 action (70% cock on open, 30% cock on close.)

With a 25# spring in the Nucleus, it's probably going to feel heavier on bolt opening than the AI... because while the Nucleus has 12 degrees more of bolt rotation over which to spread the cocking of the firing pin (72 vs 60 degrees) which will help with the lift effort, the Nucleus is a 100% cock on open action (with maybe an additional 5% overcocking on close depending on your trigger) so all the compression of the firing pin spring happens on bolt open.
The Nuke's dual cocking cams will help keep forces spread out and evened up, so it's got that going for it as well.

One important thing to note about this statement is that the 25 pound spring is likely to have a lighter bolt lift than the AI does, even though it's going to be heavier than the stock Nucleus spring.

The Nucleus has 72 degrees of cocking cams, compared to the 60 degrees of cocking cams on the AI. The nearly identical spring (only .3 pounds heavier) is being compressed a nearly identical distance (only 20 thousandths) but the work required to complete this spring compression is spread out over 12 more degrees of rotation. Unless the AI has a longer bolt handle, significantly less friction, or is breaking the laws of physics the bolt lift on it will still be heavier than the bolt lift on a Nucleus with the 25 pound spring.

Big thanks to @MarkLeupold though for crunching the numbers on the different springs, it's definitely helpful when it comes to visualizing the differences between the Nucleus spring options and other common actions on the market today.
I'm also working on some theoretical numbers on if the Nucleus had a lighter striker, just to see what kind of situation that would put us in.
 
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Steel head

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The Nuke's dual cocking cams will help keep forces spread out and evened up, so it's got that going for it as well.



I'm also working on some theoretical numbers on if the Nucleus had a lighter striker, just to see what kind of situation that would put us in.
Looking forward to seeing those numbers.
 
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MarkLeupold

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Some theoretical numbers I've had rolling around in my head the last couple days...

Remington 700 LA Nucleus 830gr 19#Nucleus 830gr 25#Nucleus 600gr 19#Nucleus 600gr 25#
Effective Striker Weight1016.4 gr830 gr830 gr600 gr 600 gr
Average Spring Force22 lbs19.6 lbs25.8 lbs19.6 lbs25.8 lbs
Potential Energy97 in-oz82.16 in-oz108.15 in-oz82.16 in-oz108.15 in-oz
Average Acceleration151.5 g's164.6 g's 217.6 g's217.6 g's301 g's
Impact Velocity15 ft/sec15.21 ft/sec17.48 ft/sec17.48 ft/sec20.6 ft/sec
Lock Time3.07 ms2.87 ms2.5 ms2.5 ms2.12 ms
Impact Momentum1.083 oz-sec.900 oz-sec1.03 oz-sec.78 oz-sec.89 oz-sec
Average Impulse Force162 lbs for 417 microseconds165.6 lbs for 340 microseconds217.8 lbs for 295 microseconds164.9 lbs for 295 microseconds221.7 lbs for 251 microseconds

830 gr striker - This is what Kiba has estimated that the striker can weigh with some triangular flat grinding on the striker body and maybe some material removal from the cocking piece. Figured ~100 gr of material removal wouldn't be completely out of the question. Calculated for 19# and 25# springs.

600 gr striker - This is purely theoretical and would have to be of a similar design to the Tubb Speedlock (his LA version weighs 550 gr, so this would be an easily achievable number in this fashion) Once again, calculated for the 19# and 25# spring.

I've come to the thought that the 19# spring is about as low as I would want to go. The paper we have been referencing states that all modern large rifle primers should go off with 75 in-oz of energy. The 16# spring doesn't cut it even in a perfect, zero-loss system. Something even stiffer than the 19# (eg. a 20 or the 22# option ARC offers) may be a better choice to account for some losses in the system.

Some thoughts: the Nucleus with the 19# spring and the 830 gr striker is an "improvement" on the M700 LA system in every way EXCEPT potential energy (this is if you believe that a lower impact momentum is in fact advantageous). I think this would be an optimal design for people looking to keep bolt lift low.

The 25# spring with the same 830 gr striker offers obvious improvements in PE, acceleration, impact velocity, lock time, and impulse force.

The 19# spring with a 600 gr striker shows very similar numbers to the 25# 830 gr system. Momentum is reduced greatly, and impulse returns to something similar to the M700 LA (albiet shorter).

The 25# spring and 600 gr striker is an extreme that I included just to see. Take a look.

My concern is that we still don't know what is actually better for setting primers off and we don't really know if a small rifle primer is supposed to be harder or easier to set off. We're just kind of comparing numbers to systems that work and hoping that will get us results.

Personally, I think the 19# spring with the 830 gr striker looks like a very promising pairing, but they're just numbers. We won't really know anything until it's proven in the field. I think we are on the right track, at least.
 

Srgt. Hulka

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I'm up to 160 rounds through mine, factory and reloads, 16# spring, and I have not disassembles the bolt and cleaned it. Still no light strikes.
I did have one go "click" on me. "Well crap." But I didn't have the magazine locked in ,and a round didn't feed. "Whew."
 

lennyo3034

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So far 111 rounds since I've put the 16lb spring back in. 0 light strikes. Mostly colder weather and all CCI450. My pin and spring are dry dry dry.

I plan on spraying down with carb cleaner again before taking it to the WAR Rifles PRS match this weekend. I'll be in squad 7 if anyone is going and wants to see how its doing.


Did a brave thing today. Replaced my 19lb spring with the stock 16lb. Will run it in the WAR Rifles PRS match.

Pin and spring are bone dry. Cleaned with carb cleaner and dried in dehydrator. Spring actually creaks when I lift the bolt.

.031" firing pin protrusion.

When I got the rifle, I had fired about 400 rounds with the 16lb spring before I started having issues. I had never cleaned it, and noticed from day 1 that the pin drop seemed "lethargic". I cleaned and installed the 19lb spring and never had an issue. Today after cleaning and drying with the 16lb spring, the pin seems to drop with more aggression than when I first got the Nucleus.

Bolt lift difference to me is very noticeable. With the 16lb spring, I can lift without rotating rifle. With the 19lb spring, I have to have a firm grip on rifle and even then I often break position.

I'm going to test it out a few times before the match, as well as clean/dry immediately before match (and probably after first day).
 

Steel head

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Hopefully my nucleus will go pew pew pew on Friday.

I wonder if I can buy a striker and lighten it up for experimental testing.
That lock time on the light striker is interesting.
 
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ThePretzel

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My experience with the 16 pound spring is that it worked so long as the firing pin assembly was kept very clean. The 19 pound spring still had occasional issues before I completely stripped the firing pin assembly of any and all grease leftover from shipping (dropped it into an ultrasonic cleaner and ran it for about half an hour).

After ~250 rounds with the 16 pound spring replaced (I swapped the 16 pounder back in after cleaning), but another cleaning fixed the issue. I cleaned it again 200 rounds after that and experienced no further light primer strikes using CCI BR4 primers (similar in hardness/thickness to the 450's).

It seems if you thoroughly clean it every 200 rounds using carb cleaner, an ultrasonic bath (I just used a 50/50 mix of 91% isopropyl alcohol and water in mine), or some elbow grease you should be fine to use the 16 pound spring. If you want more margin for error or don't want to clean it that often, the 19, 22, or 25 pound springs would be a better/safer option for you.
 

Xander3Zero

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I am curious how you guys can thoroughly clean your firing pin assembly, and then ~200 rounds later it requires cleaning again? Like where is all this grime coming from after just 200 rounds?

I don't have a Nucleus but on my TL3 I wiped the FPA clean and dry when I first got it, and hundreds of rounds later it is still clean and dry.
 
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Skunkworx

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Not sure about other owners, but the grease I use on the cocking cams seems to eventually seep/migrate onto the striker assembly itself. It’s a quick process to pull the striker assembly apart once you have done it a few times.
 
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ThePretzel

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I am curious how you guys can thoroughly clean your firing pin assembly, and then ~200 rounds later it requires cleaning again? Like where is all this grime coming from after just 200 rounds?

I don't have a Nucleus but on my TL3 I wiped the FPA clean and dry when I first got it, and hundreds of rounds later it is still clean and dry.
It's just various dirt and grime, but seemed to mostly be powder fowling (near the tip of the firing pin) and grease from the cocking cams (as mentioned by @Skunkworx ). The middle of the firing pin assembly seemed visibly clean, but the tightest tolerances (where foreign contaminants have the largest effect on ignition reliability) are up near the firing pin hole. You'll always get powder fouling on the bolt face, in/around the firing pin hole, and on the end of the firing pin.

Second time that I cleaned it I just dropped the entire bolt inside my ultrasonic cleaner to make things easy. You could probably get similar results if you just dropped it into a cup of carb cleaner, but I have no idea what the carb cleaner may or may not do to the nitrided finish so proceed at your own risk.

It doesn't take much for the reliability of the action to be compromised, it would seem, because the 16 pound spring is already on the edge of being barely enough.
 

whatsupdoc

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The basic design of the action is sound, I believe in my case that the rifle had marginal ignition due to the 16# spring + cci450's.
After cycling the spring a few hundred times it lost enough tension to stop igniting cci450's.

When I sent my bolt back i asked for both the 25 and 19 spring, I will see what they do.

Does anyone know what spring weight was installed on the PVA rifles?
 

Xander3Zero

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I would recommend using something like TW25b grease for the cocking cams and contact face of the lugs. I use a very small amount on these locations and it doesn't run or work its way into the internals of the FPA. I typically wipe the bolt face down after each outing, just using a q-tip and a drop of solvent if needed, only takes about 2 minutes.

Definitely have never noticed any fouling accumulating inside the firing pin hole and onto the firing pin. I know that some fouling will make its way in there, but there must be something about the Nucleus design that makes it more prone to this issue than other actions.

It doesn't take much for the reliability of the action to be compromised, it would seem, because the 16 pound spring is already on the edge of being barely enough.
It's unfortunate that ARC chose a pre-order to do their beta testing for them. The lengths people are going through in order to get these functioning 100% is mind boggling. Hopefully everyone can get them working to their standards and be able to enjoy their new rifles.
 

TheMammoth

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The basic design of the action is sound, I believe in my case that the rifle had marginal ignition due to the 16# spring + cci450's.
After cycling the spring a few hundred times it lost enough tension to stop igniting cci450's.

When I sent my bolt back i asked for both the 25 and 19 spring, I will see what they do.

Does anyone know what spring weight was installed on the PVA rifles?
The Hancock comes with the 19# spring
 

Kiba

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Does anyone know what spring weight was installed on the PVA rifles?
Regarding the PVA JHR actions, after Josh had some light strike issues with his test action he ordered all the JHR actions with the 19# springs; Josh covered that in the JHR thread.


Regarding the “beta testing” comments-- many people including myself have had zero issues with light strikes or FTF issues. It’s not like every action ARC has shipped is having issues otherwise we’d be seeing far more users posting in this thread. I’m going to say that if ARC experienced significant light strike issues during their own testing they would not have shipped them in the configuration they did-- but obviously some trigger, FP spring, and primer combos that they did not test (or did not test enough of) simply aren’t reliable out in the field. Perhaps their test program could have been more robust and benefitted from trying more triggers and primers, but that’s speculation not knowing exactly what combinations they tested.

I took my action out of the box, installed the trigger, screwed the barrel on, went to the range and put 200 rounds through it without even bothering to clean out all the shipping grease and lube on the firing pin and in the bolt. In that initial 200 rounds there was only 1 FTF, and it wasn’t the fault of the action—that round had a very deep primer. My other rifle wouldn’t set it off either, and only left a slight mark on the primer. This was with the original 16# spring.

Then I read the posts here about the light strike issues and disassembled the bolt and cleaned all the gunk out of the bolt and firing pin (there was quite a bit in the bolt shroud and cocking piece) and then fired another 600 rounds with zero issues and no further cleaning during that time-- still with the 16# spring.

About 2 weeks ago I decided to try the 19# spring to see if there was any difference in bolt lift… another 200 rounds since then with zero issues. Didn’t clean anything while I was swapping the springs, everything was still clean.

This is all with Remington 7.5 small rifle primers, which are known to have a fairly thick cup-- but probably not as tough as CCI 450s.

I am seriously considering buying a spare firing pin and cocking piece from ARC and putting them on a diet to test with the 19# spring. I think I can grind 3 triangular flats on the firing pin to save some weight and also remove some material from the cocking piece. Based on some rough dimensions and measurements I think it’s possible to remove about 100gr between both of them without compromising strength. Since we’re still not in agreement regarding exactly what parameter is best to ignite a primer (PE, impulse, momentum, etc) it would be interesting to see what a lightened firing pin and cocking piece with the 16# and 19# spring would do. I would probably load up some test rounds with CCI 450’s to test that. However based on the measurements of my AI, I have a hunch more spring rate is needed regardless of firing pin weight to significantly improve reliability in all situations. I do like the numbers from a ~100gr weight savings from the FP and striker combined with a 22# spring, but my gut feeling isn’t hard test data.
 

Steel head

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Got my nucleus together.
Cleaned the bolt/striker thoroughly.
Set pin protrusion to .035ish.
I did check striker drag with the spring out with my Huber trigger, there was a bit of drag but pretty minimal.
Way less than the video posted earlier.

Bolt lift effort was quite similar to my well worn in savage.
Action is considerably smoother though.
I’ll see if it goes bang tomorrow after work.
 
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Darkhorse1

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I’m 2 matches in with mine. The first match, I fired 0 rounds. That weekend SUCKED. In the last match, I had 9rds that didn’t fire. This was after I stripped the bolt of all of the grease that came from the factory in locations that it shouldn’t have been. I received the 25lb springs the day that I got back from the last match, but I haven’t installed them yet.

I hope to get this issue resolved, but I’m done with revolutionary new designs and pre-orders. Any money I potentially saved by not getting more Deviants has been lost in match and travel costs anyways.
Did you install the 25# spring and do some testing yet? ARC sent me a 25# as well when I asked them too so I could potentially be proactive vs sending in the bolt should I experience an issue (none so far but don’t have more than 200 rnds through mine yet, figured it would be good to have on hand if the gun goes down). Just wondering if the 25# would virtually guarantee reliability or not, a bit more bolt lift would be a good trade off for the reliability imo as long as it doesn’t make me come completely off target with each cycling of the bolt.
 

Triple D

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Not yet, but I plan on doing that later today and testing a few rounds tomorrow. I also have the rounds that previously didn’t go off, some that were tried twice, that I will test with.
 

lennyo3034

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Day one of the match went well, did better than expected.

Had 1 light primer strike with the 16 lb spring. It didn’t cost me anything but still concerning.

The 16 lb spring was nice from the several unstable stages we had. I think I would have had a lower score with the 19 lb spring because I wouldn’t have been able to keep my crosshairs on target as a cycled.

Trying to decide what to do for day 2. Just clean and dry or replace with 19 lb? Suggestions?
 

Eggman

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I’m 2 matches in with mine. The first match, I fired 0 rounds. That weekend SUCKED. In the last match, I had 9rds that didn’t fire. This was after I stripped the bolt of all of the grease that came from the factory in locations that it shouldn’t have been. I received the 25lb springs the day that I got back from the last match, but I haven’t installed them yet.

I hope to get this issue resolved, but I’m done with revolutionary new designs and pre-orders. Any money I potentially saved by not getting more Deviants has been lost in match and travel costs anyways.
so you didnt have any issues with light strikes when sighting in the rifle or practicing with it before the matches? or did the problems begin the day of the match out of the blue?
 

lennyo3034

Gunny Sergeant
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Apr 18, 2010
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Finished the match with only the one light strike yesterday. 200+ rounds fired. Still not great in my opinion but it did not cause issues.

I did have a double feed, which I did not think was possible with a controlled feed action.

Also had an issue with accidentally flipping the safety when cycling bolt. That really threw me off a few times. I've decided that I HATE the nucleus/Mausingfield bolt knob. I replaced that immediately when I got home.
 

Steel head

Uncouth heathen
Belligerents
Aug 3, 2014
749
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Finished the match with only the one light strike yesterday. 200+ rounds fired. Still not great in my opinion but it did not cause issues.

I did have a double feed, which I did not think was possible with a controlled feed action.

Also had an issue with accidentally flipping the safety when cycling bolt. That really threw me off a few times. I've decided that I HATE the nucleus/Mausingfield bolt knob. I replaced that immediately when I got home.
I tried a magpul magazine and all I got was push feed from it.
ARC mags almost always get me controlled round feed.
A big AI ball handle would me nice.
I’m not super excited about the bolt handle.
I’ll run it a bit longer to see if it grows on me.

So far my experience with the Nucleus has been nothing but fairly positive.
Feeds well and everything goes boom.
Got my 147 load finalized today.
 

Anderson_A

Sergeant of the Hide
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Apr 26, 2018
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Northeast Murica
Finished the match with only the one light strike yesterday. 200+ rounds fired. Still not great in my opinion but it did not cause issues.

I did have a double feed, which I did not think was possible with a controlled feed action.

Also had an issue with accidentally flipping the safety when cycling bolt. That really threw me off a few times. I've decided that I HATE the nucleus/Mausingfield bolt knob. I replaced that immediately when I got home.
I tried a magpul magazine and all I got was push feed from it.
ARC mags almost always get me controlled round feed.
A big AI ball handle would me nice.
I’m not super excited about the bolt handle.
I’ll run it a bit longer to see if it grows on me.

So far my experience with the Nucleus has been nothing but fairly positive.
Feeds well and everything goes boom.
Got my 147 load finalized today.

I got the area 419 bolt knob not sure if it’s what your looking for but it was a. Huge improvement for me
 
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lennyo3034

Gunny Sergeant
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Apr 18, 2010
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I got the area 419 bolt knob not sure if it’s what your looking for but it was a. Huge improvement for me
I replaced my knob with the 419 knob as soon as I got home. Had already ordered one.

I have a very early serial number so I will send my bolt head and extractor for updates.
 

Northernjets

Private
Belligerents
Mar 5, 2017
49
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Alberta
So I found out today my nucleus has a 25# spring.
All nucleus actions feb 19 and after have the 25# in them.
I’m tempted to buy a 19# spring.

I’m tempted to try and make my own bolt knob.
Thanks for sharing that tidbit of info. I've been wondering what spring weight they've been shipping with now. My action is apparently sitting at the exporter, so I'm hoping to get it early April.

Has anyone here tried the tear drop handle? Most pictures I've seen are of either the stock knob or the Area 419. The barbell one in the last few ARC videos looks intriguing too. Looks like a best of both worlds between the stock and AICS style ball.
 

tomcatfan

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Nov 22, 2010
383
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Southern MD.
Thanks for sharing that tidbit of info. I've been wondering what spring weight they've been shipping with now. My action is apparently sitting at the exporter, so I'm hoping to get it early April.

Has anyone here tried the tear drop handle? Most pictures I've seen are of either the stock knob or the Area 419. The barbell one in the last few ARC videos looks intriguing too. Looks like a best of both worlds between the stock and AICS style ball.
7049598
I got the egg from ARC and I like it a lot more. The old bolt knob hurt my palm when closing the bolt on stiffer reloads. As already established with the difficult to turn bolt release, I have pussy hands. The egg is much more comfortable on my pussy hands. This is much closer to what the RPR and savages have.
 

Northernjets

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Mar 5, 2017
49
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Alberta
Thanks for the photo! The tear drop definitely seems more nicely contoured for running between the index finger and thumb like my Tikka's swept Sterk handle.
 

tomcatfan

Sergeant
Belligerents
Nov 22, 2010
383
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Southern MD.
Thanks for the photo! The tear drop definitely seems more nicely contoured for running between the index finger and thumb like my Tikka's swept Sterk handle.
I still don’t have a problem opening the bolt with my index finger. It’s just more comfy closing with my palm.
 

Steel head

Uncouth heathen
Belligerents
Aug 3, 2014
749
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View attachment 7049598
I got the egg from ARC and I like it a lot more. The old bolt knob hurt my palm when closing the bolt on stiffer reloads. As already established with the difficult to turn bolt release, I have pussy hands. The egg is much more comfortable on my pussy hands. This is much closer to what the RPR and savages have.
I like that.
I’m gonna try and and make my own but it’s nice to know I have a good option if I fail.
 

MarkLeupold

On board the .25 train
Belligerents
Feb 10, 2017
394
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I went ahead and ordered the 25 pound spring today and an egg bolt knob (just to make the cost of shipping somewhat worth my while). I've got a match pretty much the first week I'll have my rifle together (great idea, right?) and I want that end all, be all solution if it starts light striking. I really don't think the bolt lift will be that bad. My mindset is just run it with conviction and treat it like any other short throw bolt. Once I get some time to do so, I may see what lighter springs will do, but I just want it to run when it should.

Does anyone have information on the Curtis Customs striker assembly? Their bolt lift looks silky smooth...I know it's in part to their roller tipped cocking piece, but damn that lift looks light...
 

Steel head

Uncouth heathen
Belligerents
Aug 3, 2014
749
215
49
Washington
I went ahead and ordered the 25 pound spring today and an egg bolt knob (just to make the cost of shipping somewhat worth my while). I've got a match pretty much the first week I'll have my rifle together (great idea, right?) and I want that end all, be all solution if it starts light striking. I really don't think the bolt lift will be that bad. My mindset is just run it with conviction and treat it like any other short throw bolt. Once I get some time to do so, I may see what lighter springs will do, but I just want it to run when it should.

Does anyone have information on the Curtis Customs striker assembly? Their bolt lift looks silky smooth...I know it's in part to their roller tipped cocking piece, but damn that lift looks light...
I’ll have the 19# spring and egg knob today.
I don’t find the 25# bolt lift objectionable, I mainly just want to see if the 19# works and if it does I’ll have an even nicer bolt lift.

I haven’t gotten my grubby hands on a Curtis but they do look interesting.
 
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hereinaz

I have no idea why I get these new labels...
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Mar 7, 2018
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Arizona
I tried a magpul magazine and all I got was push feed from it.
ARC mags almost always get me controlled round feed.
A big AI ball handle would me nice.
I’m not super excited about the bolt handle.
I’ll run it a bit longer to see if it grows on me.

So far my experience with the Nucleus has been nothing but fairly positive.
Feeds well and everything goes boom.
Got my 147 load finalized today.
As to mags and controlled round feeding, this was discussed in the "Nucleus Orders" thread and I think I posted pictures.

In short, trim the Magpul feed lips shorter and you will likely get CRF.

LONGER: The magpul have longer feed lips, so that the body of the case underneath stops pushing up as the round is released to the bolt head.

ARC mags have shorter feed lips so that when they let go of the round, the case of the round below has more force to push it up into the bolt head.

If the bolt head and extractor does not grab the round as it leaves the magazine, you will get a double feed unless you close the bolt all the way to engage the extractor.

If the extractor was controlling the round, it would be really hard to get a double feed, but I could imagine if things were really messed up.
 

MarkLeupold

On board the .25 train
Belligerents
Feb 10, 2017
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As to mags and controlled round feeding, this was discussed in the "Nucleus Orders" thread and I think I posted pictures.

In short, trim the Magpul feed lips shorter and you will likely get CRF.

LONGER: The magpul have longer feed lips, so that the body of the case underneath stops pushing up as the round is released to the bolt head.

ARC mags have shorter feed lips so that when they let go of the round, the case of the round below has more force to push it up into the bolt head.

If the bolt head and extractor does not grab the round as it leaves the magazine, you will get a double feed unless you close the bolt all the way to engage the extractor.

If the extractor was controlling the round, it would be really hard to get a double feed, but I could imagine if things were really messed up.
I need to do some experimenting with my Springfield over the summer, but how do CRF rifles function when they're a system (1903, M70, etc)? Do their internal magazines have extremely short lips? If so, how are the cartridges retained within the magazine?
 

proff49

Private
Minuteman
Feb 16, 2018
46
16
12
For you guys changing springs, what are you using to do it? I think using the washer is going to be a bitch trying to compress a 25lb spring.
 

NovaHunter

Private
Belligerents
Mar 22, 2011
155
44
34
Virginia
I have about 1000 rounds on my nucleus since last July. Ran it in the WAR Rifles match this weekend (Squad 11). I've been running 6.5x47 with FGMM small rifle primers. Have shot 3 day matches, and some 1 day matches with it.

I've only ever cleaned the outside of the bolt. Haven't taken it apart yet nor did I degrease the inside of the bolt assembly. Never had a light primer strike. Running a Huber trigger now, and ran a Timney for the first few months.
 
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