Nucleus Light Primer Strikes

Apr 23, 2017
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Kansas City MO
After cleaning the bolt, and swapping in the Bix N Andys trigger, my son ran 25 rounds today with no failures. Statistically, this means nothing, but it made my day so far! Will report here with any further developments. FYI , the 6BR is serial # 10X and my friends 6.5 x 47L is serial # 24X.
 
Mar 22, 2017
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I went to the range yesterday to put the first rounds thru my Nucleus build. It is a SA Left Hand in .223 with a Huber 2 stage trigger. I had light strikes with both American Eagle 55gr FMJ and Hornady 55gr Steel Match. 20 to 25% failure to fire with both types of ammo. I like everything else about the action. I will be ordering the 19 pound spring today and the 22 pound spring when it is available. I hope one of the new springs solves the problem.
 

flyer

Sergeant of the Hide
Apr 25, 2018
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It sounds like changing the spring is a real bitch so I would try disassembling the bolt and cleaning out the grease before changing the spring.

I'm going to do that preemptively today on my Nucleus.
 
Dec 17, 2017
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Boulder, CO
It sounds like changing the spring is a real bitch so I would try disassembling the bolt and cleaning out the grease before changing the spring.

I'm going to do that preemptively today on my Nucleus.
I, too, would strongly recommend doing that. They shipped my Nucleus with a LOT of rust preventative all over it, and it could be that this is getting up inside the actions and slowing the firing pins down from what they should be doing.

In fact when I took mine apart again this past week to re-install the 16 pound spring I found even more of the original oil that I ended up wiping off, or at least I'd assume it was the original stuff since I never added more inside the bolt.

As an update for this weekend's results, I shot 30 rounds for a quick test with new bullets using my original 16 pound spring and new TT Diamond. Didn't have any issues, so my fingers are crossed that it was just some strange interaction with the trigger itself. The next match I intend to go to is on the 13th, so if I end up going I'll report back again once I get more rounds through the gun with this combination.
 
May 11, 2017
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CA
I realize this might be an issue for some, but hopefully it's only affecting a few. I've put over 250 rounds through mine in the last two days, zero issues. This includes handloads using both Federal 210M as well as BR4 primers, and 4 different types of factory ammo. I preemptively switched to the 19lb spring and use a Bix'n Andy trigger FWIW. I love this action so far
 
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flyer

Sergeant of the Hide
Apr 25, 2018
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I disassembled my bolt and found less grease than I was expecting.

I found that a Q-tip with the cotton mostly removed is the perfect size to clean out the firing pin hole in the bolt head.

I took off some grease, not all. I left some on the cocking cams, bolt lugs and the bolt head retaining pin. Hopefully enough to keep things lubed but not enough to gunk up the firing pin.

If I get any light strikes after that, I'll just get the 19lb firing pin spring because I'm not sure I would be able to keep the bolt significantly cleaner than it is now.
 
Jan 21, 2012
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I took mine out for the first time on Saturday and shot 50 test loads. It functioned perfectly, no light strikes or FTF's. The primers had very good firing pin indents on them, so I don't see any issues with the spring.
 
Dec 17, 2017
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Boulder, CO
One thing I'm interested in trying, since Nitriding is helpful for corrosion resistance and I live in a dry enough climate to feel comfortable having no oil at all inside my bolt, is dropping the entire bolt (disassembled) into my ultrasonic cleaner filled with some isopropyl alcohol to try and flush out all oil present within the bolt assembly. From that point I could lubricate the necessary pieces (bolt lugs, locking cams, etc.) and know that the rest of them should be bone dry. I didn't have issues previously, but I imagine it definitely would hurt to give my bolt a good deep cleaning since it's been out in the wind and dust for several matches.
 
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BLKWLFK9

come at me bro
Feb 13, 2017
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One thing I'm interested in trying, since Nitriding is helpful for corrosion resistance and I live in a dry enough climate to feel comfortable having no oil at all inside my bolt, is dropping the entire bolt (disassembled) into my ultrasonic cleaner filled with some isopropyl alcohol to try and flush out all oil present within the bolt assembly. From that point I could lubricate the necessary pieces (bolt lugs, locking cams, etc.) and know that the rest of them should be bone dry. I didn't have issues previously, but I imagine it definitely would hurt to give my bolt a good deep cleaning since it's been out in the wind and dust for several matches.
When u do lube the cams and such, try some of the Wilson combat ultima-lube. feels like taking a couple pounds off the bolt lift.
 

Science.Ninja

This space for rent
Sep 16, 2017
32
4
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Georgia
Check, then double check after a couple dozen rounds, the tighteness of the actual firing pin assembly in the bolt. Had similar issues (light strikes) with Bix n Andy. Problem was that after about 20-40 rounds the screw that holds the firing pin assembly in the bolt would work is way out. Not like fall out... but loosen up enough to cause light strikes. Had to tighten it down three times out of 100 rounds, and tightening it always fixed the problem immediately. I just added a drop of locitite the fourth time I screwed it down tight. No issues since.
 
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Dec 17, 2017
227
122
43
Boulder, CO
Check, then double check after a couple dozen rounds, the tighteness of the actual firing pin assembly in the bolt. Had similar issues (light strikes) with Bix n Andy. Problem was that after about 20-40 rounds the screw that holds the firing pin assembly in the bolt would work is way out. Not like fall out... but loosen up enough to cause light strikes. Had to tighten it down three times out of 100 rounds, and tightening it always fixed the problem immediately. I just added a drop of locitite the fourth time I screwed it down tight. No issues since.
When you talk about the screw holding the firing pin assembly into the bolt, are you referring to the bolt shroud itself becoming unscrewed from the bolt body or are you talking about something else?
 

Ando

Private
Aug 18, 2007
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HI
Fired one box prime 6.5 CM ammo through my brand new assembled Nucleus.
100% function, though I did disassemble and clean out most of the oil from inside the bolt and firing pin channel/spring area.
 
Dec 17, 2017
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Boulder, CO
Went to the range again with more BR4 primed Lapua brass with the 16 pound spring in and had no issues. That's 70 rounds down the tube now with no light primer strikes, which is longer than the Calvin Elite could go without light strikes using the original 16lb spring (it had 1 in about 200 rounds with the 19 lb spring).

I've got a match on Saturday, so hopefully all continues to go well with the 16 lb spring and TT Diamond there. I love the trigger though, it feels great.
 
Apr 4, 2013
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Still no issues here. I've been through 200 Prime 6.5c, and 40 Hornady ELD. I'll be shooting a match tomorrow with the Hornady. I bought the heavy spring just in case.
 

jsthntn247

Gunny Sergeant
Feb 25, 2009
1,050
31
48
Mississippi
Ran the first 20 rounds to break in the barrel and zero the scope with the nucleus and pva barrel. Just loaded some Norma 130s 10 k off with 41 gr of Re 16. Shooting and cleaning between shots was averaging about 1/2”. Last 5 shots after barrel was fouled barely ragged a hole. No light strikes with 16lb spring and 205’s.
 
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