Nucleus prefit barrels

6cmShooter

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Is there anybody that is doing a shouldered nucleus prefit shouldered barrel in 6.5 addiction. I know there are places that do the shoulder prefits but I cant seem to find anybody that has that chambering as an option.
 

BenW

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I recommend you check your action with the recoil lug in place to make sure the distance from the bolt face to the front of the lug is in spec to the ARC interface drawing. My Archimedes is not, and it caused headaches with my prefit barrel headspace.
 
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Steel head

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I recommend you check your action with the recoil lug in place to make sure the distance from the bolt face to the front of the lug is in spec to the ARC interface drawing. My Archimedes is not, and it caused headaches with my prefit barrel headspace.
My barrel guy says the same thing, he’s seen some variation beyond acceptable for a prefit.
 

6cmShooter

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Only issue I've had as of now with prefit barrels is a barrel not screwing on to the action cause it wasnt threaded currently from where I got it from.
 

Steel head

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Only issue I've had as of now with prefit barrels is a barrel not screwing on to the action cause it wasnt threaded currently from where I got it from.
If it didn’t thread in I’d question the smith.
From what I’ve gathered threads are fine, just headspace requirements/tendon length differences.
 
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6cmShooter

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I sent it back yesterday. But they said they cant guarantee itll fit without the action cause according to them they've never had that problem before. Which I found out today is a lie and alot of people have had issues with there barrels not threading in or being chambered correctly on an array of actions they do prefits for.
 

Steel head

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I sent it back yesterday. But they said they cant guarantee itll fit without the action cause according to them they've never had that problem before. Which I found out today is a lie and alot of people have had issues with there barrels not threading in or being chambered correctly on an array of actions they do prefits for.
Yea, it’s a savage small shank thread.
My smith and Shilen barrel prefits don’t seem to having a problem with it.
 

Skunkworx

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My nuke ran into issues getting a pva prefit to work, the head space ended up being a little short. I’ve had other barrels work so it’s hit or miss sometimes.
 

6cmShooter

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My nuke ran into issues getting a pva prefit to work, the head space ended up being a little short. I’ve had other barrels work so it’s hit or miss sometimes.
Havent had issue with the headspace being wrong the only issue I've ran into is the tenon threads not being cut deep enough so it wont screw on.
 

BenW

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My nuke ran into issues getting a pva prefit to work, the head space ended up being a little short. I’ve had other barrels work so it’s hit or miss sometimes.
Did PVA fix the headspace for you? How did it shoot after it was fixed? I’m in the same boat right now. My prefit headspace was short and PVA is recutting the chamber after measuring my Archimedes action. If I were them, I’d stop offering ARC prefits.
 

Long Range 338

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Did PVA fix the headspace for you? How did it shoot after it was fixed? I’m in the same boat right now. My prefit headspace was short and PVA is recutting the chamber after measuring my Archimedes action. If I were them, I’d stop offering ARC prefits.
I've had a couple now and both are spot on. I think you kind of run that risk offering prefits. There have been issues even with the AI prefits so its nothing new.
 
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Long Range 338

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Havent had issue with the headspace being wrong the only issue I've ran into is the tenon threads not being cut deep enough so it wont screw on.
Could this be that it is actually a prefit for a Savage large shank? Strange dimension to not work on a prefit barrel.
 

6cmShooter

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Could this be that it is actually a prefit for a Savage large shank? Strange dimension to not work on a prefit barrel.
I measured it to another barrel I had from the same place and it all measured the same except the threads had a slight flat on top of them and the minor diameter was .005 larger than my other barrel which fits perfect maybe even a little big as I have to make sure it's dead nut inline with the action or it wont screw in so it's at the higher end of the allowed thread tolerances
 

Franko

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Reading this is making me nervous as I have two different (and new) ARC actions (Mausingfield and Archimedes). Is my only option to send both actions to a gunsmith and pay to have them measured to make sure they are in spec?

I'm really not interested in buying my first shouldered prefit and finding it won't fit...
 

Triple D

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I sent it back yesterday. But they said they cant guarantee itll fit without the action cause according to them they've never had that problem before. Which I found out today is a lie and alot of people have had issues with there barrels not threading in or being chambered correctly on an array of actions they do prefits for.
Was this a Preferred Barrel Blanks prefit?
 

6cmShooter

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The appeal of prefits for me was I didnt have to send the action out to have a barrel spun up for it. If I wanted to send the action out I would have bought a krieger or bartlien cut rifle barrel like I usually do and paid to have my smith fit it to my action and wait how ever long it would have taken him to do it.
 

Steel head

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Reading this is making me nervous as I have two different (and new) ARC actions (Mausingfield and Archimedes). Is my only option to send both actions to a gunsmith and pay to have them measured to make sure they are in spec?

I'm really not interested in buying my first shouldered prefit and finding it won't fit...
Well LRI is doing prefits for them still so there is that.


I’m wondering If the lug is the culprit or something else.

I haven’t had issues but I’m rocking the barrel nut barrels.
The threads on my Nuke have fit the Three prefit barrels from two sources absolutely beautifully.
 

6cmShooter

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I was running a criterion 6cm barrel with a nut and it fit beautifully. But I wanted to shoot different calibers with out having to constantly pull the action out of the stock to loosen the barrel nut
 

Jcaplinger199

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Well LRI is doing prefits for them still so there is that.


I’m wondering If the lug is the culprit or something else.

I haven’t had issues but I’m rocking the barrel nut barrels.
The threads on my Nuke have fit the Three prefit barrels from two sources absolutely beautifully.
I wanted a prefit because the gun smith around here quoted a really Long wait time to cut a barrel. i spoke with LRI first and they won’t do a prefit for a mausingfield without the action in hand only the nucleus. I thought this odd since ARC told me that now all 3 of their actions has the same Measurements. I spoke with PVA after seeing they sold them on their website and they confirmed they did not need the action in hand. I ordered a PVA guess I should have read this thread first... hopefully I get lucky and don’t have any issues once I get it.
 

Steel head

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I thought so to. That’s when I emailed ARC to ask about if there was anything special about the mausingfield and got the response regarding the 3 Actions now having the same measurements.
There was a few early Mausingfields that had Rem 700 threads I think
 

StraightShooter77

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Is there anybody that is doing a shouldered nucleus prefit shouldered barrel in 6.5 addiction. I know there are places that do the shoulder prefits but I cant seem to find anybody that has that chambering as an option.
Straight Jacket Armory does custom prefits for the ARC Nucleus https://straightjacketarmory.com/pr...any-nucleus-prefit-proof-carbon-or-stainless/

For the 6.5 Addiction chamber. Our attitude is YES WE CAN do it. At present we don't have that reamer yet. What we do for customers wanting a caliber we don't have a reamer for is we split the the cost on the reamer and keeps the reamer after we chamber your prefit. Deal?

Tom aka StraightShooter77

Straight Jacket Armory -Evanston, Wyoming
www.straightjacketarmory.com
(307) 707-3181 Ext 1
 
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357Max

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i spoke with LRI first and they won’t do a prefit for a mausingfield without the action in hand only the nucleus.
This has come up before and I'm going off memory here. I looked for the old thread & can't find it.
Not a negative to any other smiths, but I'm pretty sure LRI has chambered more Mausingfield's then anyone else. I tend to listen carefully when LRI ways in on the ARC products.

LRI in that thread stated 2 reasons for not wanting to do Mausingfield shouldered prefits.

1. The toroidal lugs can result in up to .002 variation between actions (This may have since been tightened). The machining required to those lugs and mating receiver abutments is far more complex then typical square lug actions.
2. The Mouser style extractor unique to the mausingfield, used to require fitting on the earlier mausingfield's to ensure they would control round feed properly.

Ted also replied in that thread and said ARC had since pulled the extractor manufacturing completely in house & spent considerable time tweaking it so the fitting is no longer necessary. I don't recall if Ted said when this change became effective i.e. M5/M7???

Having said all that. I called LRI about getting a shouldered barrel for a Nucleus and Chad recommended sending the action.
I am a machinist and understand the reasons why without having to question him. Actually I very much respect him & his honest desire to do the job right.
I have no doubt LRI or another reputable smith can cut a shouldered nuc prefit that will head space, but why wouldn't I want to send it. That is exactly the kind of service I'm after. Why settle for + - .0012 when by sending the action it I'll get + - .0001 from LRI's ideal based on their experience.

An analogy based on my background would be:
Sure I can pin fit your custom $1500 set of race pistons without the DLC'd toolsteel wrist pins. I'm a very good machinist that can hone them to dead nuts mid book .9905 and ship them. But I know damn well the tool steel pins vary in size & some company's pre-machine for the coating and some don't.
So without the pins in hand I have little choice but to shoot for mid spec (think SAAMI). I'm sure they'd fit but my goal when pin fitting isn't that they fit, it's to set a specific clearance based on the racing application in which they'll be used. And that is based on my experience as to what clearance performs best for given application. In this scenario without the pins to measure the clearance could be .0002 - .001, Whereas if I had the pins I'd set it to .0006 - .0008 depending on application.

Full disclosure: I probably have more variables then is typical for a nuc prefit. In my case it was a Nucleus 1.1 bastard child with a wild cat chambering.
I had barrel sent directly to LRI from vendor, shipped my action to them, and rented a new reamer and go guage + 1 new brass sent from another vendor.

All 3 items hit LRI within about a week.
LRI bought the reamer I'd rented (saving me a few bucks) chambered it, threaded the muzzle, loaded a round & test fired it within 1 week.
Now my action dimensions are on file along with a pc of brass fired in my chamber. Any future replacements or new calibers I want chambered are just a phone call to LRI.

I've got a new Mausingfield M7 That's slated for the new Manner MCS-TCS group buy stock. It will be going to LRI when I decide on a caliber. Leaning 6GT, but hoping Berger or Hornady will get onboard with 25 cal.