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Nucleus Light Primer Strikes

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.
I chucked the washer in the trash. I just do it with my hands. The 25 lber was tough but doable. I found it’s easier if you only thread in the striker retract screw a couple threads. Maybe if you use grippy gloves it may help if you’re having issues with slipping.
 
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.

Ted showed a rendering of a knurled tool a while back that looked like it would make the job very easy, but it's still not available on their website.
 
I chucked the washer in the trash. I just do it with my hands. The 25 lber was tough but doable. I found it’s easier if you only thread in the striker retract screw a couple threads. Maybe if you use grippy gloves it may help if you’re having issues with slipping.
Thanks for the advice. I'll have to play with it and see what happens.

Ted showed a rendering of a knurled tool a while back that looked like it would make the job very easy, but it's still not available on their website.
I checked the website last night and saw it was still unavailable. Can't say I was surprised.
 
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.
The 25# does put up a good fight.
I’m working on a small fixture to make things easier.
 
Thats what I'm afraid of.

I put the washer on top of my vise jaws towards the outside edge, with the striker facing down, pushed it through and then unthreaded the lock nut with my other hand. It wasn't bad at all doing it that way. I am going to run about 100 rounds sat on the 25# and see how it feels. It's noticeable, but not too bad if it will give me peace of mind on reliability.
 
I put the washer on top of my vise jaws towards the outside edge, with the striker facing down, pushed it through and then unthreaded the lock nut with my other hand. It wasn't bad at all doing it that way. I am going to run about 100 rounds sat on the 25# and see how it feels. It's noticeable, but not too bad if it will give me peace of mind on reliability.

Something using a vise was what I figured would be the easiest...helps to be able to use your body weight effectively.
 
Thanks for the ideas guys. I thought about using my vice as a press but it isn't large enough. From your responses it doesn't seem to be as difficult as I was expecting. I am going to have find out what an egg handle is, though. I'm not much of a cook!
 
Thanks for the ideas guys. I thought about using my vice as a press but it isn't large enough. From your responses it doesn't seem to be as difficult as I was expecting. I am going to have find out what an egg handle is, though. I'm not much of a cook!

It’s the egg bolt knob on the ARC website.
 
This is all you need. It was easy to swap the 25 lber in and out without issue.
 

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On your nucleus when you hold the bolt body are you able to rotate the bolt head back and forth?
On my replacement bolt head I have a small amount of rotation between the bolt head and the bold body.
The new bolt head pin hole seems to be slightly larger than my old bolt head as I do not remember my old bolt head having any play.

Anyway ARC replaced the 16lb spring with what I believe is the 19 lb spring, and as I asked gave me the 25 lb spring in a bag just in case.
cocking with the 19 lb spring does not seem bad at all.
 
On your nucleus when you hold the bolt body are you able to rotate the bolt head back and forth?
On my replacement bolt head I have a small amount of rotation between the bolt head and the bold body.
The new bolt head pin hole seems to be slightly larger than my old bolt head as I do not remember my old bolt head having any play.

Anyway ARC replaced the 16lb spring with what I believe is the 19 lb spring, and as I asked gave me the 25 lb spring in a bag just in case.
cocking with the 19 lb spring does not seem bad at all.

Mine has a bit of play similar to my old savage but less.

I was surprised at how easy bolt lift got with the 19#

It runs like a scalded cat now.

My Trigger pull went from 2lbs 3ozs to 1lb 15 ozs.
 
Decided to order the 25# springs at the same time I ordered a couple different bolt knobs to try. ARC emailed me a tracking number within 90 minutes, so it appears they are trying to stay on top of things at the shop.

I have to say, the long barbell is extremely comfy... but so is the egg. I think I prefer the long barbell because it provides a nice finger groove to lift the bolt with the side of your index finger just like the stock knob. I may pick up a short barbell to try too, I didn't realize the long barbell was so much longer than the stock bolt knob.

I also tried the 25# spring... it's a bit fun to hang onto the washer while trying to compress the spring and start the castle nut without launching everything into the ceiling. The 25# springs makes a very noticable difference in bolt lift compared to the 19# spring, but it's still not terrible IMO... especially with the long barbell knob since it gives you more leverage.

Since my 223AI is still running great with the 19# spring I'll stick with it for the lighter bolt lift but keep the 25# spring in my range bag just in case. I'd like to see a 22# spring offered too, perhaps in conjunction with a lightened firing pin and cocking piece...

It would be nice to see a status update from ARC regarding the availability of the redesigned bolt heads and the knurled firing pin tool.

At some point I'd like to feel a Nucleus with the 25# spring right next to an Archimedes with the 25# spring to compare them.
 
I bought the short and long barbells, I love the feel of both over the stock knob. I run the short for now.

I’ve tried the 16, 19, and 25 lb spring. Rem 7.5 primers must be hard to light. They laugh at the 16lb spring. The 19 didn’t set off 6 out of 50.

I took those 6 light struck rounds back to home and ran them through my Forster coax press on board primer to double check the were fully seated. Then I swapped the 25lb spring and they still wouldn’t fire. It just makes a huge ass crater.
 
Decided to order the 25# springs at the same time I ordered a couple different bolt knobs to try. ARC emailed me a tracking number within 90 minutes, so it appears they are trying to stay on top of things at the shop.

I have to say, the long barbell is extremely comfy... but so is the egg. I think I prefer the long barbell because it provides a nice finger groove to lift the bolt with the side of your index finger just like the stock knob. I may pick up a short barbell to try too, I didn't realize the long barbell was so much longer than the stock bolt knob.

I also tried the 25# spring... it's a bit fun to hang onto the washer while trying to compress the spring and start the castle nut without launching everything into the ceiling. The 25# springs makes a very noticable difference in bolt lift compared to the 19# spring, but it's still not terrible IMO... especially with the long barbell knob since it gives you more leverage.

Since my 223AI is still running great with the 19# spring I'll stick with it for the lighter bolt lift but keep the 25# spring in my range bag just in case. I'd like to see a 22# spring offered too, perhaps in conjunction with a lightened firing pin and cocking piece...

It would be nice to see a status update from ARC regarding the availability of the redesigned bolt heads and the knurled firing pin tool.

At some point I'd like to feel a Nucleus with the 25# spring right next to an Archimedes with the 25# spring to compare them.


The upgraded bolt head is a noticeable improvement. The bolt is much easier and smoother to close.
 
I bought the short and long barbells, I love the feel of both over the stock knob. I run the short for now.

I’ve tried the 16, 19, and 25 lb spring. Rem 7.5 primers must be hard to light. They laugh at the 16lb spring. The 19 didn’t set off 6 out of 50.

I took those 6 light struck rounds back to home and ran them through my Forster coax press on board primer to double check the were fully seated. Then I swapped the 25lb spring and they still wouldn’t fire. It just makes a huge ass crater.

It's a case by case thing, because I had zero issues with the 16# spring and 7.5 primers. Only one that didn't go bang with the 16# spring was set way too deep, the primer pocket on that one piece of brass was way out of spec.

The upgraded bolt head is a noticeable improvement. The bolt is much easier and smoother to close.

I figured as much... the lead in ramps are rather minimal on the 1st design bolt heads and if you run the bolt slow that transition from the small ramp to the primary lug surface is pretty obvious. Have any pics of the back of ramps and lugs on your Rev 2 bolt head? I'd like to see how they compare to Rev 1, I'm sure they're larger and more gradual ramps.
 
It's a case by case thing, because I had zero issues with the 16# spring and 7.5 primers. Only one that didn't go bang with the 16# spring was set way too deep, the primer pocket on that one piece of brass was way out of spec.



I figured as much... the lead in ramps are rather minimal on the 1st design bolt heads and if you run the bolt slow that transition from the small ramp to the primary lug surface is pretty obvious. Have any pics of the back of ramps and lugs on your Rev 2 bolt head? I'd like to see how they compare to Rev 1, I'm sure they're larger and more gradual ramps.
7052602
 
Decided to order the 25# springs at the same time I ordered a couple different bolt knobs to try. ARC emailed me a tracking number within 90 minutes, so it appears they are trying to stay on top of things at the shop.

I have to say, the long barbell is extremely comfy... but so is the egg. I think I prefer the long barbell because it provides a nice finger groove to lift the bolt with the side of your index finger just like the stock knob. I may pick up a short barbell to try too, I didn't realize the long barbell was so much longer than the stock bolt knob.

I also tried the 25# spring... it's a bit fun to hang onto the washer while trying to compress the spring and start the castle nut without launching everything into the ceiling. The 25# springs makes a very noticable difference in bolt lift compared to the 19# spring, but it's still not terrible IMO... especially with the long barbell knob since it gives you more leverage.

Since my 223AI is still running great with the 19# spring I'll stick with it for the lighter bolt lift but keep the 25# spring in my range bag just in case. I'd like to see a 22# spring offered too, perhaps in conjunction with a lightened firing pin and cocking piece...

It would be nice to see a status update from ARC regarding the availability of the redesigned bolt heads and the knurled firing pin tool.

At some point I'd like to feel a Nucleus with the 25# spring right next to an Archimedes with the 25# spring to compare them.

I shot my nucleus today with the 19# and a was very pleased with the bolt lift and trigger feel.

No issues whatsoever.

I’ll carry the 25# in my tool kit just in case.

I very pleased I stuck to my guns and bought the nucleus regardless of what problems some may of had.

I got my springs and bolt handle very quickly and I saw on their site today that they have nucleus actions in stock now ready to go.
Ted said 2019 was going to be better and so Farlex it’s seems so.
 
Went and shot about 130 rounds today with the 25# spring (shooting prone and off tripod) I hadn’t had any FTF’s with the 16# but this thread made me nervous about reliability/consistency so figured I’d trade a little bolt lift for reliable function peace of mind if anything. The bolt lift is definitely heavier than with the 16#, but I was able to run multiple rapid strings of 10 rounds and not come off target (distances ranged from 270-500 with rapid strings). I’m also gonna try LRI’s bolt knob since I prefer to grip the bolt knob vs using my index finger (not really gonna happen anyway with the 25# installed) to cycle it. I’m pretty content at this point with the rig in general, and the recent customer service from ARC was solid (much better from earlier communications so I think they have ironed out some things which is great). This is my first custom action, so I can’t compare bolt lift etc to others besides factory Tikka and Remy actions, but my $.02 would be just put in the 25# spring and have fun. It cycles extremely smooth and virtually frictionless in my configuration (shouldered barrel barloc cut from PVA; TT Diamond; AICS AX chassis; and leprechaun dust).
 
Is this normal?

Yep, neither the crosspin nor bolt head are press fits so there's going to be a little movement. Both my long and short action have it. The bolt head is going to align to the case and lugs when closed and in battery.
 
The upgraded bolt head is a noticeable improvement. The bolt is much easier and smoother to close.

Sorry if this has been covered, how did you get a new design bolt head? Is Ted now replacing the old design? I have one of the first ones made and have issues with hard bolt close and lift. I'm eager to get the new one before the season gets going.
 
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Sorry if this has been covered, how did you get a new design bolt head? Is Ted now replacing the old design? I have one of the first ones made and have issues with hard bolt close and lift. I'm eager to get the new one before the season gets going.
Just contact them. They’ll exchange bolt heads on a one to one basis and send out striker springs if you ask for them.
 
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Hi,
I was just wondering if people are getting light strikes in only short actions or do the long actions behave in the same manner.
Just thinking of picking up a long action.
 
Add me to the list of misfires. At the range now and rounds 6-10 went pew. 3 out of 5 on rnds 11-15 misfired. [Edit: Rnds 16-20 fired. I re-chambered the 3 duds and 2 went bang] It's 29 degrees shooting factory 140ELDM.
Haven't read the whole thread but
looks like I need a 19lbs spring.
This is total rounds on rifle, been a long cold winter; first 5 shots fired weeks/months ago all went bang and I cleaned between each one (no bolt disassembly), same box of ammo and it was just as cold or colder with first 5.
 
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Is this normal?
Yes, it's a floating bolt head and that's part of what you're trying to make happen when you have swappable bolt faces like that. The little bit of wiggle in combination with the toroidal lugs in ARC actions allows them to ensure a square lock up with full contact even if their tolerances on the receiver and/or bolt head are slightly wider than one-piece bolt actions like an Impact Precision or Remington 700.
 
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Add me to the list of misfires. At the range now and rounds 6-10 went pew. 3 out of 5 on rnds 11-15 misfired. [Edit: Rnds 16-20 fired. I re-chambered the 3 duds and 2 went bang] It's 29 degrees shooting factory 140ELDM.
Haven't read the whole thread but
looks like I need a 19lbs spring.
This is total rounds on rifle, been a long cold winter; first 5 shots fired weeks/months ago all went bang and I cleaned between each one (no bolt disassembly), same box of ammo and it was just as cold or colder with first 5.
If you didn’t read the whole thread then maybe you missed that a number of people have had success with just a complete bolt and firing pin disassembly and complete cleaning. I personally cannot tell you if this will resolve your particular issue, but it is certainly worth trying before buying a heavier spring.
 
Thank you. I had read the first half awhile back during the wait for my barreled action. I'll dissemble and clean. And read the thread to make sure my issues are consistent with others. Thanks again
 
It's a case by case thing, because I had zero issues with the 16# spring and 7.5 primers. Only one that didn't go bang with the 16# spring was set way too deep, the primer pocket on that one piece of brass was way out of spec.



I figured as much... the lead in ramps are rather minimal on the 1st design bolt heads and if you run the bolt slow that transition from the small ramp to the primary lug surface is pretty obvious. Have any pics of the back of ramps and lugs on your Rev 2 bolt head? I'd like to see how they compare to Rev 1, I'm sure they're larger and more gradual ramps.


7053143

Hard to get a good pic with it installed.
 
I wish they’d update the bolt head retaining pin to be captured by the bolt body itself vs using the striker to do that. One has to imagine the pin is rubbing on the striker on some level, and when using the “wheeler” method to check distance to lands it would be great if you didn’t have to cobble something together to keep that pin in place.
 
I wish they’d update the bolt head retaining pin to be captured by the bolt body itself vs using the striker to do that. One has to imagine the pin is rubbing on the striker on some level, and when using the “wheeler” method to check distance to lands it would be great if you didn’t have to cobble something together to keep that pin in place.

Just use the screw and washer to restrain the striker while doing that test or adjusting your FL die; screw it in until the striker is held against the washer. The screw and washer removes all the load of the striker spring on the bolt so you can feel what's going on, and the firing pin stays in place to retain the crosspin.

On a friend's TL3 I just shove a length of copper wire in the back of the bolt body to take the place of the firing pin to retain the crosspin and bolt head while doing that task... It's even easier on the nucleus using the striker take down screw and washer.
 
Just use the screw and washer to restrain the striker while doing that test or adjusting your FL die; screw it in until the striker is held against the washer. The screw and washer removes all the load of the striker spring on the bolt so you can feel what's going on, and the firing pin stays in place to retain the crosspin.

On a friend's TL3 I just shove a length of copper wire in the back of the bolt body to take the place of the firing pin to retain the crosspin and bolt head while doing that task... It's even easier on the nucleus using the striker take down screw and washer.
I’ve done the above method, but you still have to deal with the resistance of the bolt shroud threads interacting with the bolt body which detracts from the feeling needed. It’s basically like fucking a girl with and without a rubber. Sure it’ll work but the feeling is much different. Scotch tape is another method that works as well.
 
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I’ve done the above method, but you still have to deal with the resistance of the bolt shroud threads interacting with the bolt body which detracts from the feeling needed. It’s basically like fucking a girl with and without a rubber. Sure it’ll work but the feeling is much different. Scotch tape is another method that works as well.

True, you will still have the drag of the bolt shroud threads. Not a big deal for setting an FL die in my opinion, but I can see it being a problem for finding the lands using that method which you need a more sensitive feeling for.

Still, just use a piece of wire in the back of the bolt to retain the crosspin... Using tape to hold it in place sucks.
 
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True, you will still have the drag of the bolt shroud threads. Not a big deal for setting an FL die in my opinion, but I can see it being a problem for finding the lands using that method which you need a more sensitive feeling for.

Still, just use a piece of wire in the back of the bolt to retain the crosspin... Using tape to hold it in place sucks.

I've also seen a video where you just push the cartridge into the chamber with your finger. I'll try to find the reference, but I would think that would give you great feel for finding the lands. Works similarly to the Wheeler method. I was going to give it a try on my Nucleus.
 
I have an early Nucleus serial number 53. So far I have around 2000 rounds on it with the original 16# spring and have a Bix’n Andy TacSport trigger. In brass with large rifle primers I have used Fed GM215M primers without issue and for small primer brass I am using Fed GM205MAR primers. The 205MAR primers have a thicker cup and I have not had an issue until this weekend. I had one round at the Lonestar match when I pulled the trigger and could hear the firing pin release but the round didn’t fire. Ejected the round and continued on without issue. When I picked up the unfixed round after I shot the stage it didn’t have a mark from a light primer strike. I tossed it back in the chamber and it fired. Not sure why that round didn’t go off but I never ran into an issue the rest of the day.
 
I have an early Nucleus serial number 53. So far I have around 2000 rounds on it with the original 16# spring and have a Bix’n Andy TacSport trigger. In brass with large rifle primers I have used Fed GM215M primers without issue and for small primer brass I am using Fed GM205MAR primers. The 205MAR primers have a thicker cup and I have not had an issue until this weekend. I had one round at the Lonestar match when I pulled the trigger and could hear the firing pin release but the round didn’t fire. Ejected the round and continued on without issue. When I picked up the unfixed round after I shot the stage it didn’t have a mark from a light primer strike. I tossed it back in the chamber and it fired. Not sure why that round didn’t go off but I never ran into an issue the rest of the day.

What top sear are you using? I'm using the pro with low sear but changed to the 25# spring just for a piece of mind.
 
Took my Nuke out on it's maiden journey today. It performed great while fire forming 50 rounds of 6xc with CCI 200 and Timney CE 2 stage. It's a PVA barreled action, so not sure if it's 16# or 19# spring.

Gotta say I wasn't sold on the action when it was clamped in my vise. But after spending some time behind it dry and live firing, I really like it..so far.
 
Took my Nuke out on it's maiden journey today. It performed great while fire forming 50 rounds of 6xc with CCI 200 and Timney CE 2 stage. It's a PVA barreled action, so not sure if it's 16# or 19# spring.

Gotta say I wasn't sold on the action when it was clamped in my vise. But after spending some time behind it dry and live firing, I really like it..so far.
Earlier someone said the PVA builds had a 19#

Mine came with a 25# and I recently switched to the 19# and feel it’s perfect.

The more I shoot mine the more I like it.
 
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Earlier someone said the PVA builds had a 19#

Mine came with a 25# and I recently switched to the 19# and feel it’s perfect.

The more I shoot mine the more I like it.

I agree..while I only have 59 rounds through it so far, I have cycled the bolt a bunch and it is smooth. It control round fed great also from a magpul 5 rounder.
 
Gotta say I wasn't sold on the action when it was clamped in my vise. But after spending some time behind it dry and live firing, I really like it..so far.

That was my feeling as well. Feels way better on the range than the bench.

Also, after working through some initial issues, I’m having 100% reliable ignition using the #19 spring with a Huber Concepts trigger.
 
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A little update.

Shooting at a new long range spot I got invited to and with the 19# spring nucleus action has been great.

Absolutely flawless and my rifle is everything I hoped for.

We got 3 shooters new to the long range game in the 1000 meter club yesterday with my rifle.

All of them within 3-4 shots.