Nucleus Light Primer Strikes

OK, so I replaced my spring with the 19# and did some testing. I had five ftf out of 31 hand loads. I had both CCI and Federal primers fail to fire. All those that failed, did fire when tried again. This is better than the 40% failure I was seeing on handloads before, but still not great.

The factory hornady (147 Eld-M) I shot had no rounds fail to fire.

When I replaced the spring it looked like the bolt was lubricated with a grease. The grease may be heavy enough to slow the pin down just slightly, so I am going to strip the bolt, clean out all the grease and lube with something lighter. Also going to replace the trigger (Timney) with something else.
 
OK, so I replaced my spring with the 19# and did some testing. I had five ftf out of 31 hand loads. I had both CCI and Federal primers fail to fire. All those that failed, did fire when tried again. This is better than the 40% failure I was seeing on handloads before, but still not great.

The factory hornady (147 Eld-M) I shot had no rounds fail to fire.

When I replaced the spring it looked like the bolt was lubricated with a grease. The grease may be heavy enough to slow the pin down just slightly, so I am going to strip the bolt, clean out all the grease and lube with something lighter. Also going to replace the trigger (Timney) with something else.

Hmmm!
Is it possible to reassemble the bolt without the spring then see by pushing the firing pin by hand while holding the trigger back to see if there is any interference.
 
Hmmm!
Is it possible to reassemble the bolt without the spring then see by pushing the firing pin by hand while holding the trigger back to see if there is any interference.

Possibly, but I don't fancy removing and installing the spring again. I am not a big fan of the bolt's assembly/disassembly procedure. Getting the spring off is OK, but for me getting the spring back on sucks.

I've stripped down the bolt, cleaned and removed all the grease, lubed with oil, and have another trigger to test with. Going to the range to test tomorrow, so hopefully I will have some good data to report back with.
 
Possibly, but I don't fancy removing and installing the spring again. I am not a big fan of the bolt's assembly/disassembly procedure. Getting the spring off is OK, but for me getting the spring back on sucks.

I've stripped down the bolt, cleaned and removed all the grease, lubed with oil, and have another trigger to test with. Going to the range to test tomorrow, so hopefully I will have some good data to report back with.


Looking forward to your range report, Captain.
 
Any tips to removing the firing pin spring? I have the washer but when I push down on it, the spring wants to stay on the keyed locking washer that meets up with the castle nut.

And when I compress the spring, it doesn’t seem to move far enough to allow the keyed washer to spin freely of the nut. There is not enough clearance.
 
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Any tips to removing the firing pin spring? I have the washer but when I push down on it, the spring wants to stay on the keyed locking washer that meets up with the castle nut.

And when I compress the spring, it doesn’t seem to move far enough to allow the keyed washer to spin freely of the nut. There is not enough clearance.

The screw you add to the back of the bolt (that releases the tension to allow you to unscrew the firing pin assembly from the rest of the bolt), compresses the firing spring. You need to make sure you loosen that screw to allow the spring to compress again. If you have already done that, then...umm...

And when you reassemble good luck trying to rotate the keyed nut to go on correctly while trying to compress the spring then getting the nut back on. After the nut is secure you will need to tighten the compression screw you add to the back so the spring is compressed again, then you can screw the assembly back into the bolt.
 
So, good day at the range today. 1 round failed to fire from 75 hand loads. I put that in the margin of error for hand loads so I say that is pretty good.

To recap, was seeing 40% fail to fire on hand loads (CCI 200 primers). Replaced spring with 19#, and cleaned grease out of bolt and lubed with a lighter oil. Seems much better now.

Edit: Didn't replace the trigger since I wasn't seeing significant number of failures. All rounds fired with Timney 517.
 
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So, good day at the range today. 1 round failed to fire from 75 hand loads. I put that in the margin of error for hand loads so I say that is pretty good.

To recap, was seeing 40% fail to fire on hand loads (CCI 200 primers). Replaced spring with 19#, and cleaned grease out of bolt and lubed with a lighter oil. Seems much better now.

Edit: Didn't replace the trigger since I wasn't seeing significant number of failures. All rounds fired with Timney 517.

Was the failure a light primer strike?
Have you had a failure to fire before with your hand loads on other rifles?
 
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I had issues getting the spring off at first.

To compress it enough you're going to have to lean on it with almost your full weight pressing it against the floor. Until I did that I thought it was impossible and that there simply wasn't enough clearance.
 
Was the failure a light primer strike?
Have you had a failure to fire before with your hand loads on other rifles?

Seconding @whatpsupdoc here. The only time I've had handloads fail is when the primer pockets were not cleaned well and the primers were not fully seated. The firing pin expended all of its energy fully seating the primer. Putting the unfired/struck cartridge back in resulted in the rounds firing in most instances, but a couple took 3 attempts.

I've had rifle rounds that I forgot to charge with powder as well. Those end up with a fired primer but the bullet doesn't move. There isn't enough energy in the primer to move the bullet at all. Taking the bullet out you see black carbon all over the base of the bullet.

I have 120 rounds through my Nucleus at this point, 100 handloads and 20 factory 140gr ELDMs. No failures to fire so far.
 
So far in 2018 I have reloaded and fired over 2300 rounds for 4 different rifles with zero misfires including a 105 year old savage.
Im not 100% sure but I do not recall ever having a center fire rifle misfire, I guess it could be luck.

Today I go to shoot trap with my 1970's 1100, last time was about 8 or 9 months ago.
On the 66th round gun goes click WTF, I eject the round look its a light primer strike. No freaking way I mutter under my breath.
Load a new shell call for the bird gun fires, next bird click and again click, I am done.

While driving home I am thinking there better be something broken in this gun. It ends up being a broken firing pin.

Unless there is something amiss on a new action or some kind of component tolerance/interference issue it should be 100% reliable.
 
Never said it was. But when you've got brass that's tight in the chamber and the thing hits the primer without going bang it's clearly not a problem with headspace.

While you may certainly have some other issue with the Timney putting excessive upward pressure on the sear or even the firing pin spring being too light, headspacing off a piece of brass isn't a good way to roll unless running false shoulders.

I've done exactly as you and have seen exactly what you are seeing here.

Run false shoulders and see if your issues disapear.

I'd bet money they do.
 
While you may certainly have some other issue with the Timney putting excessive upward pressure on the sear or even the firing pin spring being too light, headspacing off a piece of brass isn't a good way to roll unless running false shoulders.

I've done exactly as you and have seen exactly what you are seeing here.

Run false shoulders and see if your issues disapear.

I'd bet money they do.
I'm pretty sure you misunderstand entirely what I just said. The chamber is tight enough that when I first ran the brass through the gun most rounds were a pretty snug fit (including a number of those that failed to fire) because I only ran an expander ball through the virgin brass to avoid making it undersized and causing precisely the problems you are referring to.

I have since fired the same pieces of brass through the rifle several times, and had 2 more light strikes after swapping to the 19 pound spring but before my TriggerTech arrived. It's not a headspace issue when brass fired in that chamber and then appropriately resized using the same technique that's worked for me in 5 different guns and several thousand rounds this year alone without a single light primer strike up to this point.

When I swapped out the trigger I unloaded several of the pieces with light primer strikes that I had been holding onto and loaded them again with new primers, new powders, but the same bullets (can't waste those 105 Hybrids right now) with exactly the same load they originally held. Didn't size them except to give the brass the proper neck tension again after the previous bullet was pulled. They worked fine, as has every single round I've loaded since switching to the TriggerTech Diamond without changing anything about how I'm loading them.

Headspace is important to get precisely right if you want to adhere strictly to the caliber specifications so that you can shoot any ammunition of that caliber in it. My rifle, being chambered in 6BR, will never see a single round of factory ammo and this barrel will never touch brass besides what I've already shot through it. If the headspace on a round is already snug from my method of headspacing (and it's happening even with fireformed brass that has been appropriately sized to fit my chamber just right), running a false shoulder will change precisely nothing.
 
I received my 19# spring today, but not until after I hit the range.

Over the weekend, I disassembled the bolt, well, most of it. I couldn't get the retaining nut/washer off so I soaked it with brake cleaner and cleaned it up best I could.

After cleaning, I reassembled everything.

Hit the range today after work with the same exact ammo I've had FTFs with. I fired twenty rounds today with zero issues. Now we're getting somewhere. I'm wondering if the spring was just dirty and the grit/grime was causing the spring to not push the firing pin the way it should be, meaning the spring is essentially too weak.

I get home from the range and the new spring was waiting for me so I again accepted the challenge of having to remove the old one. I was able to compress the spring with one hand, and loosen the nut with the other hand and finally remove the old spring. What a pain in the dick.

After cleaning the firing pin and assembly, I got to work putting the new spring on.

I had to use the provided washer for assembly, and another set of hands as there isn't a snowball's chance in hell you're going to accomplish this task alone.

After everything was put back together, I installed the bolt back in the rifle.

The first thing I noticed was the amount of force necessary to open and close is the bolt is noticeably higher.

And not just a but higher, I'm talking fire a really hot round and have to lift like you got a pair hard.

Now, the bolt was dry during this process, so I take the bolt apart to apply some oil to the inside moving parts.

So, took the bolt out, applied a thin layer of oil to the spring, and some grease to the lugs. This helped out a lot, but the bolt lift is still harder than before. I can't imagine running a 22# spring.

I'll be hitting the range at least once more this week and then it's up to SD for a match. I'll post how things go as I get more time.

I'm embarrassed to say that I'm bringing a back up gun, just in case.
 
While you may certainly have some other issue with the Timney putting excessive upward pressure on the sear or even the firing pin spring being too light, headspacing off a piece of brass isn't a good way to roll unless running false shoulders.

I've done exactly as you and have seen exactly what you are seeing here.

Run false shoulders and see if your issues disapear.

I'd bet money they do.

How did you have problems when you headspaced off brass and you had problems? I have used brass to headspace and want to make sure I don't miss something. I see what you are saying that false shoulders could help. I ran my chamber tight to the brass. How will I see the problem?

For what it is worth, I headspaced my Nucleus 6xc off the brass and have had no problems running with a Huber trigger. I have over 300 rounds through with no problems, running CCI large rifle primers and Norma brass.
 
I received my 19# spring today, but not until after I hit the range.

Over the weekend, I disassembled the bolt, well, most of it. I couldn't get the retaining nut/washer off so I soaked it with brake cleaner and cleaned it up best I could.

After cleaning, I reassembled everything.

Hit the range today after work with the same exact ammo I've had FTFs with. I fired twenty rounds today with zero issues. Now we're getting somewhere. I'm wondering if the spring was just dirty and the grit/grime was causing the spring to not push the firing pin the way it should be, meaning the spring is essentially too weak.

I had the same issue with a Mausenfield action earlier this year. The grease/oil that ARC uses for packaging gums up the firing pin enough to slow it down. If you don't clean it before using, then you may see light strikes. I was able to resolve this quickly by contacting ARC who first recommend that I clean it thoroughly before sending in the bolt or changing the FP spring.
 
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Grease in the bolt will pack into the front of the bolt and slow the firing pin.

The first thing I noticed was the amount of force necessary to open and close is the bolt is noticeably higher.

And not just a but higher, I'm talking fire a really hot round and have to lift like you got a pair hard.

Now, the bolt was dry during this process, so I take the bolt apart to apply some oil to the inside moving parts.

So, took the bolt out, applied a thin layer of oil to the spring, and some grease to the lugs. This helped out a lot, but the bolt lift is still harder than before. I can't imagine running a 22# spring.

I'll be hitting the range at least once more this week and then it's up to SD for a match. I'll post how things go as I get more time.

I'm embarrassed to say that I'm bringing a back up gun, just in case.

Make sure you put some grease on both cocking cams.
 
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Was the failure a light primer strike?
Have you had a failure to fire before with your hand loads on other rifles?

I have not had issues with rounds failing to fire before. The strike on this round looks hard enough to have set it off, to me at least.

IMG-0574.JPG
 
I'm glad some of you have been able to get in touch with the sum bitches. I sent my payment and FFL documentation last week. Havn't got a shipping notice or have no idea if they received my ffl paperwork, they damn sure took the money within minutes. Have called and sent emails with no response. Their customer service sucks major dick, right up there with PTG in my book.
 
Hit the range yesterday with the 19# spring. I fired about 40 rounds with no issues.

When I assembled the bolt with the new spring, I did put some oil on the spring. I'm not sure if it's necessary, but I'm hoping it doesn't cause any issues.

I'm heading out again tonight to confirm some velocity numbers, but after yesterday, things are looking up.

All rounds went bang when I pulled the trigger.
 
I saw my Nucleus at the FFL for the first time today. The bolt had some streaks of black grease coming out of the extractor area. I'll be sure to clean it well.
 
I saw my Nucleus at the FFL for the first time today. The bolt had some streaks of black grease coming out of the extractor area. I'll be sure to clean it well.
Definitely clean it up good. They put a lot of oil all over it for rust prevention, which I personally think is a plus because it guarantees your action isn't going to rust even if it ends up in a super humid conditions during shipping.

Just fully take it apart and clean off all the oil they added, then add oil or grease where appropriate (the cocking cams and bolt lugs, mostly). Also make sure to take off the rail and clean underneath there before tightening the screws down with a little loctite - I didn't at first and actually had my rail slip around a little bit after some bumpy travel. Everything else on the gun was still tight and torqued properly, and the issue disappeared once I removed the rail (turns out they put liberal amounts of oil there too) and then reattached with a touch of loctite. My mistake entirely there though.
 
Definitely clean it up good. They put a lot of oil all over it for rust prevention, which I personally think is a plus because it guarantees your action isn't going to rust even if it ends up in a super humid conditions during shipping.

Just fully take it apart and clean off all the oil they added, then add oil or grease where appropriate (the cocking cams and bolt lugs, mostly). Also make sure to take off the rail and clean underneath there before tightening the screws down with a little loctite - I didn't at first and actually had my rail slip around a little bit after some bumpy travel. Everything else on the gun was still tight and torqued properly, and the issue disappeared once I removed the rail (turns out they put liberal amounts of oil there too) and then reattached with a touch of loctite. My mistake entirely there though.

What did you torque the rail screws at?
 
What did you torque the rail screws at?
When I put the rail back on I just torqued them to "good and tight" with some blue loctite on the screws and a thin line placed underneath the rail itself. Not cranking on it hard enough to risk stripping the screws or damage the threads, but pretty tight otherwise. I only really use a torque wrench on my action screws and scope rings.
 
Well... Friday on sight in day, I had 8 of 20 with light primer strikes. Could visibly see they were light. Saturday had 1 failure out of 100. Ammo both days was from same batch of hand loads. This was with 19# spring.

Do you plan on trying a different trigger? It would be interesting if say a TriggerTech solved your problems. These primer problems are making me real nervous about my Nucleus. I don’t think I’ve ever had a primer fail to ignite in either of my Bighorns or my Defiance in the 7k+ total rounds fired through them.
 
I can't say I've had any issues at all. 400 rounds with CCI 450 and every one went off. Both 6 Dasher and 6 creedmoor. I was getting SDs around 10 with the dasher so I was wondering if a heavier spring would help reduce SDs. However once I switched to the 6 Creedmoor barrel my SDs dropped to 2-3 with almost any load. Don't see a reason to switch to a 19 lb spring.

Using triggertech diamond
 
When I put the rail back on I just torqued them to "good and tight" with some blue loctite on the screws and a thin line placed underneath the rail itself. Not cranking on it hard enough to risk stripping the screws or damage the threads, but pretty tight otherwise. I only really use a torque wrench on my action screws and scope rings.

I was just curious as the Fixit sticks page of torques for the mausingfield list 45 in/lbs. Both use 8-36 screws. I would just be nervous about 45 but that could be totally out of line. I will not derail the light primer strike thread any further however. Thanks.
 
Do you plan on trying a different trigger? It would be interesting if say a TriggerTech solved your problems. These primer problems are making me real nervous about my Nucleus. I don’t think I’ve ever had a primer fail to ignite in either of my Bighorns or my Defiance in the 7k+ total rounds fired through them.

I forgot to add that I switched to a Triggertech Diamond before this weekend. The light strikes this weekend were with the TT and not the Timney.

I see no rhyme or reason why one day it has a high rate of failure, one day not.
 
I forgot to add that I switched to a Triggertech Diamond before this weekend. The light strikes this weekend were with the TT and not the Timney.

I see no rhyme or reason why one day it has a high rate of failure, one day not.
That is really strange. I hope you get it figured out and working properly. Keep us updated if you don't mind.
 
First rounds out of my nucleus last Saturday, had three fail to fire, out of fifteen rounds. Got disgusted and put it away. Load is 6mm BR lapua cases CCI450 primers 105 Scenar bullet with 29.8 grs Varget, Calvin elite two stage trigger. After reading in this thread, I cleaned all oil and grease from the bolt and sprayed lugs and cocking cams with dry moly lube then put a dab of anti seize on lugs and cams. I have a Bix and Andys two stage, bought for another rifle on hand, and will try that before I take it back to the range. Strangely, my friend just built a nucleus in 6.5 x 47, and he had no failures in about fifty rounds on the same day, with the same batch of primers and a Jewel trigger. I hope, that with enough anecdotal evidence, we can determine what the real fix to this problem is.
 
I'm running a 6.5cm with the timney Calvin Elite 2 stage and have yet to have a light strike or failure to fire. ran it in the guardian match last weekend and it ran like a scolded dog. This is with the #16 spring. I've got about 360 rounds through it with 0 issues of any sort. I absolutely love mine and it sucks to see others not having the same success as me.
 
I'm running a 6.5cm with the timney Calvin Elite 2 stage and have yet to have a light strike or failure to fire. ran it in the guardian match last weekend and it ran like a scolded dog. This is with the #16 spring. I've got about 360 rounds through it with 0 issues of any sort. I absolutely love mine and it sucks to see others not having the same success as me.

That has been my experience with my 6XC, has ran like a champ in a two day and a one day comp. Well over 300 rounds running a Huber 2 stage (without cleaning the bolt). Not a single issue that isn't related directly to me being a knucklehead. I have a long action I have yet to set up, so I hope it doesn't extend to those.

Not sure if he updated here, but my buddy Squatch switched from a Timney to a Huber trigger and the problem went away so far even with the 16# spring.
 
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