When is using a Prefit barrel the right option

Article 4

WKR
Joined
Mar 4, 2019
Messages
443
Location
The Great Northwest
Looked this up and didnt see this discussed.

I am a fan of prefits, in certain applications. I am more of a fan of using a smith fit barrel the vase majority of the time. They both work but IMO and IME the smith fit barrel works better and is CONSISTENTLY more accurate.

Prefits work if
  • you want to change it yourself and are willing to go with whatever reamer spec and bbl spec the bbl maker uses.
  • Maybe you are short on time or dont have a good smith and wanna learn yourself. Great! Big fan of self sufficiency and learning as you go
  • Wanna buy a bbl vise, maybe a torque wrench, and gauges and understand how to read a reamer spec sheet? Again, if you wanna learn great but are you sure?
  • If you are good with a SAAMI chamber and a reamer that may or may not have been used five, eight, or maybe 12 times without replacement or ensuring it is still in spec, they get checked sure but not checked with your action
  • If you are willing to go with any barrel that is chambered by "anyone" I an NOT casting dispersions here but at some point someone got trained on the process and is doing it on their own the first time....are we absolutely sure that the guaranteed .001 headspace is consistent with YOUR action in your bench at home?
  • By the time you purchase gauges, you have spent the money to have a smith do it. Yes, you should use the gauges...safety first!!!

Personally, I will always use a smith built barrel process. Here is why:
  • I can spec my own reamer or use a shop reamer to control specs and freebore
  • Not every single action and prefit is ever going to be as exact as hand measuring and fitting. Too many hands, machines, and possible variations.
  • Being able to run the same caliber and replacing barrels will be more likely and the results more consistent using a smith
  • I can buy my own reamer and if I shoot one gun a lot, I can use it from bbl to bbl
  • I know of not a single benchrest shooter, the guys that are interested in sub 1/4 MOA accuracy, use pre fits. That in itself is important for anyone trying to build the absolute most accurate rifle they can.

So if you wanna try it, all good. I think pre fits can work in a lot of ways. But what if it doesnt, are you good with going through the process of returning it, finding out why, or wasting the precious time needed to spin another one on and hope you get the right one.


Aaaaaaaaaaaaannnnd go! LOL
 
OP
Article 4

Article 4

WKR
Joined
Mar 4, 2019
Messages
443
Location
The Great Northwest
Prefits work. Gunsmith built barrels work.

Shooter's choice.
True
Guess to me, after I spend 1000 bucks on a prefit carbon PROOF bbl it might run If so, great - go for it.

It could run even more like 1100 adding tax and shipping.

When I buy that same bbl blank at 700 and pay a smith 400 bucks and get one that I KNOW is perfect and a perfect fit to my action, I have the piece of mind and confidence it is 100% right for the same price.
 
Last edited:

Wrench

WKR
Joined
Aug 23, 2018
Messages
5,665
Location
WA
Asking for and getting the barrel curve @ 12:00 is not happening in pre fits.
 

Fujicon

FNG
Joined
Feb 26, 2024
Messages
57
Built mine with a Proof prefit on a Terminus action. Used go/no-go gauges from Pacific Tool to ensure perfect fit. Works wonderfully accurate. Don't have experience with Smith, but prefit (at least that Proof/Terminus combo) works quite well.
 
Joined
Jun 12, 2019
Messages
1,258
you want to change it yourself and are willing to go with whatever reamer spec and bbl spec the bbl maker uses.
Most of the prefits I see are done by gunsmiths, not barrel makers. TS Customs, Stuteville Precision, Blue Mountain Precision, Southern Precision Rifles (aka Bugholes ), LRI, and most well known rifle builders can do prefits. Yes, Proof does their own prefits but that's by no means the majority of the market.
If you are good with a SAAMI chamber and a reamer that may or may not have been used five, eight, or maybe 12 times without replacement or ensuring it is still in spec, they get checked sure but not checked with your action
You aren't necessarily restricted to SAAMI chambers with prefits. I just ordered one last week and I had the choice (for a 6CM) to either go with a SAAMI chamber or a 0.135 freebore. My guess is to some extent smiths who do prefits would be able to accommodate you.
If you are willing to go with any barrel that is chambered by "anyone" I an NOT casting dispersions here but at some point someone got trained on the process and is doing it on their own the first time....are we absolutely sure that the guaranteed .001 headspace is consistent with YOUR action in your bench at home?
Again refer to the list above of all the very well known gunsmiths that do prefit barrels. Do I have confidence in them? Yes I do.
I can spec my own reamer or use a shop reamer to control specs and freebore
I'm not convinced you can't choose your own reamer from a gunsmith like LRI or other custom rifle builders. I'd bet you can.
Not every single action and prefit is ever going to be as exact as hand measuring and fitting. Too many hands, machines, and possible variations.
If the action is the sort with tight enough tolerances to take a prefit, is that miniscule difference (real or imagined) really big enough to affect your precision for hunting purposes? If you were trying to set the 1000 yard benchrest record sure, but I think there are practical limits to what people actually need.
Being able to run the same caliber and replacing barrels will be more likely and the results more consistent using a smith
Why would that be more consistent? Just order a prefit in the cartridge you're shooting currently and throw it on when your existing barrel goes.
I know of not a single benchrest shooter, the guys that are interested in sub 1/4 MOA accuracy, use pre fits. That in itself is important for anyone trying to build the absolute most accurate rifle they can.
Benchrest shooters also use barrel tuners despite there being no body of evidence showing they work. And how well do your goals actually line up with benchrest shooter goals? Is your rifle 30 pounds with a 50 power scope on it? How much precision are YOU and your system actually capable of taking advantage of? NRL and PRS shooters use a bunch of prefits and seem to be able to hit targets at long range. I'm not saying that NRL/PRS are as practical gear-wise as hunting but they're a hell of a lot closer than benchrest.

It seems like you're assuming that it's either the barrel manufacturer doing prefits or some summer intern at a no-name gun shop. Also, rifle builders can measure your action once (to make you feel better or to actually improve the process, your call) and then make prefits for it based on their measurements. So it doesn't even have to be sight-unseen if that makes you feel weird.
 
Joined
Feb 24, 2012
Messages
4,643
Location
Colorado
I’ve only tried a few prefits. All were awesome. I have a prefit 6 cm proof on a tikka action. It shoots factory ammo wonderfully
 

Marbles

WKR
Classified Approved
Joined
May 16, 2020
Messages
3,711
Location
AK
I'd bet money you can find stories of a barrel done by a smith for a specific action that does not shoot.

Shooting in general has a lot of Voodoo BS, Benchrest appears to take that to a whole new level of OCD VBS, beyond that, the conditions differ so much from my shooting I would question the validity of taking even well collected data with statistically significant findings and assuming it applies to me.

Whenever possible, I buy my own tools and do my own work. The advantage of that with barrels is there can be very minimal down time for replacement. Whenever I get around to putting a new barrel on my Tikka, the factory 308 barrel will be available if for some reason I want to shoot 308, or I shoot out the new barrel and don't have the money to order another at the moment.

Headspace gauges are good tools to own. Headspace changes throughout the life of the rifle anyway.
 

Marbles

WKR
Classified Approved
Joined
May 16, 2020
Messages
3,711
Location
AK
Care to elaborate on this statement?
May be a false conclusion that wear effects headspace given the need to check it on old rifles, and the more I think about it, the more I realize what that was based on probably did not check headspace at all (go/no-go gauges for M2s).

The more I think about it, if the lugs are being driven back, or the action stretching, I'm not sure I would want to keep using the action.

Pretty sure he is referring to throat erosion.
No, because headspace is based on the datum line of the chamber, not the throat.
 
Joined
Mar 31, 2019
Messages
3,301
Location
Weiser, ID
May be a false conclusion that wear effects headspace given the need to check it on old rifles, and the more I think about it, the more I realize what that was based on probably did not check headspace at all (go/no-go gauges for M2s).

The more I think about it, if the lugs are being driven back, or the action stretching, I'm not sure I would want to keep using the action.


No, because headspace is based on the datum line of the chamber, not the throat.
Nailed it, most people are not correct in their assumptions about what head space is and isn't.
 

Syncerus1

FNG
Joined
Jan 23, 2024
Messages
41
Can someone send in a crew with machetes please? I'm so far in the weeds I do believe I'm in the Long Grass in TZ once again. I know Jumbo is in here, I just can't see him...
 
Top