Prefit barrel question

patriot07

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Oct 17, 2017
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I know it's a dumb question - if I want to go to 6.5 creedmoor, and I have a 243 or 308, I can screw in a shouldered 6.5 CM prefit barrel and it should headspace correctly without any problem? In theory at least? As long as it's a 308 bolt face, the bolt and bolt face don't know or care what the barrel is chambered for?
 
I know it's a dumb question - if I want to go to 6.5 creedmoor, and I have a 243 or 308, I can screw in a shouldered 6.5 CM prefit barrel and it should headspace correctly without any problem? In theory at least? As long as it's a 308 bolt face, the bolt and bolt face don't know or care what the barrel is chambered for?
correct. you should check headspace to be certain with go no go guages but all those are interchangable wth a simple barrel swap because same boltface.
 
I know it's a dumb question - if I want to go to 6.5 creedmoor, and I have a 243 or 308, I can screw in a shouldered 6.5 CM prefit barrel and it should headspace correctly without any problem? In theory at least? As long as it's a 308 bolt face, the bolt and bolt face don't know or care what the barrel is chambered for?

In theory, yes. In reality, maybe not.

The bigger question is what action are you planning on using?

If it's something like an older Remington, you'll need to let a gunsmith fit and chamber the shouldered barrel.
OR, use an unshouldered barrel with the nut, which is what most people do now.

If your action is something like an Origin, which is actually designed to allow for shouldered prefits, rock on with a shouldered prefit or a nut barrel. The choice is yours.
 
I know it's a dumb question - if I want to go to 6.5 creedmoor, and I have a 243 or 308, I can screw in a shouldered 6.5 CM prefit barrel and it should headspace correctly without any problem? In theory at least? As long as it's a 308 bolt face, the bolt and bolt face don't know or care what the barrel is chambered for?

A big part of this answer depends on the action that you are running, whether the pre-fit is designed for that action, and who is doing the chambering.

In theory, a good action and reputable gunsmith should provide your answer with a "yes". However, factory actions and questionable gunsmiths can turn your answer into a disaster at the range.

It never hurts to check headspace.
 
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A big part of this answer depends on the action that you are running, whether the pre-fit is designed for that action, and who is doing the chambering.

In theory, a good action and reputable gunsmith should provide your answer with a "yes". However, factory actions and questionable gunsmiths can turn your answer into a disaster at the range.

It never hurts to check headspace.
Tikka CTR action, PVA osprey prefit

I don't have gauges so I'll have to figure that out (amazon out of stock on everything it seems)...but I never really planned on rebarreling without gauges anyway, even if it "should" fit
 
Tikka 243, 22-250, or 308 action with a 6.5 cm PVA osprey prefit for a Tikka
Then yeah, it should work just fine. 99% chance youre good to go.


I do always check just for confidence/peace of mind. An ounce of prevention is worth a pound of cure.
You dont have to do any of this, Im just typing for knowledge.

I bought a creedmoor go gauge from forster/manson/ptg whoever it was in stock. They may not be identical but they will be close enough. You can even use factory ammo/unfired brass as a "half-ass but better than nothing" go gauge, just make sure your bolt is stripped or your safety is on=careful.

Insert the gauge into the chamber and the bolt should close on it. If its tight but does thats a tight match chamber. Not closing on a go doesnt mean its bad, I bet the ammo is good too and its just a difference between gauge manufacturers.
I then add a layer of scotch tape to the back of it and try to chamber and close the bolt to transform it into a no-go gauge of sorts. Sometimes it closes, sometimes it doesnt. If it doesnt you know your no-go gauge has worked.
If it does close then Ill add a second layer of tape, see if it closes.
If it does again repeat with a third layer. In this manner you can use your reloading headspace comparators to measure the go gauge and see exactly how much longer it gets with the tape before it wont close. Each layer is about a .0025 increment in length so you can fairly accurately see how long the chamber is in relation to the go gauge.
 
Tikka CTR action, PVA osprey prefit

I don't have gauges so I'll have to figure that out (amazon out of stock on everything it seems)...but I never really planned on rebarreling without gauges anyway, even if it "should" fit

I agree with the post above stating that you've got a 99% chance at success for good headspace with those two companies.

Again, it never hurts to check though.

Best of luck.
 
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