Barrel questions for new build

[Badseed]

Im building a new rifle and have found myself in analysis paralysis for making a decision on the barrel. The rifle will be a 6.5 prc used primarily for hunting.

Barrel type: Im leaning towards carbon fiber with the main goal of reducing weight and being stiff enough to maintain POI for short strings of shots at target. If Im being honest, I have never had a CF barrel so I am curious to try it out also.

Manufacturer: so many options but most smiths seem to prefer benchmark or proof. Benchmark barrels are slightly heavier which is a negative when trying to save weight. I have to assume that both barrels are equally accurate so does it make a difference on which manufacturer I choose?

Barrel length: Im torn between 22 and 24”. I live in a state that does not care about my hearing so I can’t run a can. Most of my hunting is done in the mountains and brush so a shorter barrel would be nice, I think. My other rifles have 24” barrels and they work fine but with a muzzle brake on they start to get a little long. Ive done a bit of research and it seems likes the 6.5prc looses 16-24 fps/in when going from 24 to 22” so the velocity hit isn’t substantial. Currently Im leaning towards a 22” barrel but I can get a 24” barrel for about $200 less than a 22” so Im curious if anyone has experience with both a 24” and a 22” barrel. Is there a notable handling difference between the barrels?

Twist: I am building the rifle on a medium action to allow me to use any of the long high BC bullets. However, my hunting bullets have to be mono copper so I will probably be using 120-131 gr bullets mainly. Knowing that I want to use or try 156gr bergers at some point I need a 1:7.5 twist minimum for stability. My concern is that some of the lighter bullets will exceed 300k rpms and start coming apart mid flight. Looking for peoples experience with different twists and bullet stabilities.


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[XLR]

If I was in your shoes I would go 22" Benchmark or Bartlein carbon fiber with a 1:7.5 twist. The 22 inch will allow you to get plenty of speed while staying on the shorter side of overall rifle length. The 7.5 twist will work great for the 156s but that is also the recommended twist for the 124 and 129 grain hammers.

 

[Mag_7s]

I am also into a build with my first carbon wrapped barrel. I went with Proof, only because I got a really good deal. If all pricing was equal, Bartlein would be my first choice. Most I have talked to about Proof have had nothing but positive feedback. My gunsmith was the only one who has said a few things that has me concerned. He said about 10% of the PR barrels he spins up dont shoot that well. However, everyone i personally know that has a PR loves them and all are <.75 moa guns.
If you absolutely can't use a can, I would personally go with a 24" tube and a short brake like a Salmon River Chub, I like a little more performance.

 

[ResearchinStuff]

The only proof I've ever been around doesn't shoot quite right, groups are about double what a similar build with a steel bartlein does. The 10% of fiber wrapped barrels are lousy mentioned above has been repeated by some pretty knowledgeable folks on this forum too.

Also, carbon wrapping doesn't actually save weight over a thinner steel barrel. So, unless you're going to use a can and want the increased stiffness and fatter muzzle threads, all that wrapped barrel is doing is increasing weight and cost.

 

[Beaverdog]

I have a carbon six 6.5 prc prefit in their magnum contour i ordered during their black friday sale. Its 20" i run with a can, its a beautiful barrel that shoots lights out. They use a modified reamer to avoid the clicker issue. Im still going through the break in process but its pushing factory 143 eldx 2825fps on average.

 

[Mag_7s]

I have a carbon six 6.5 prc prefit in their magnum contour i ordered during their black friday sale. Its 20" i run with a can, its a beautiful barrel that shoots lights out. They use a modified reamer to avoid the clicker issue. Im still going through the break in process but its pushing factory 143 eldx 2825fps on average.

What is a clicker issue?

 

[wind gypsy]

24"+ Brake isn't obnoxious to me and I think it's a pretty good length for non-suppressed magnum rifle. I wouldn't pay $200 to go 22" for sure. Velocity is nice if you're stuck with monos too.

I don't buy that a carbon is going to be any stiffer or less likely to string shots than steel barrel of the same weight. The worst barrel i've owned in regards to opening up with strings is a custom carbon barrel. Only benefit is more meat on the muzzle for bigger threads at a given weight point.
Other options would be:
1. getting a custom steel contour that bells at the end for threads (my preference)
2. buying a heavier contour with enough meat and having the smith contour it down except for the muzzle where threads are (2nd preference)
3. Aggressively fluting a heavier contour (don't like, have had poor results but not a large enough sample size to be confident fluting was to blame)

The other thing is a 6.5 isn't a large bore so you could have it threaded 1/2"x28 or 9/16" vs 5/8 threads. There are thoughts on wanting to keep more meat at the muzzle than 1/2" threads but also a lot of high end smiths have no reservations (GAP has always used 1/2x28 threads on 6.5 saum extreme hunter line for example). I certainly don't know if it makes a difference but tend to error on the side of caution if possible.

 

[wind gypsy]

What is a clicker issue?

The PRC die "problem"

There are a number of people experiencing sizing issues with the PRC case. When designing a chamber, brass, and resize die there is no one size fits all. We want good hard case brass, but its harder to size. We dont want sloppy chambers either. I have experience with designing reamers with...

www.longrangehunting.com

Cliff notes: PRC cases (and others) are prone to expanding where brass is thick directly above the case head. Because of how thick the brass is here, it either is not sized down enough by dies or tends to spring back and/or easily expand again on subsequent shots. The clearance between SAAMI spec reamers and fired brass that has expanded at this location is tight, resulting in stiff bolt lift often accompanied by an audible "click" when lifting the bolt. Preferred solution is using a reamer with a larger dimension at the base of the case for more clearance. Lots of people also open up existing SAAMI chambers in this area.

Edit to add: @Badseed if you are handloading i would ask your smith if they have a reamer (like the AW2) with added clearance at the case web to combat clickers. If you're just shooting factory ammo it doesn't matter.

ETA again: Bartlein or benchmark is where id go if doing carbon. Bartlein will be heavier yet. My #4 bartlein carbon is basically the same weight as a #3 bartlein steel IIRC which isn't that light for a sporter.

 

[Samson7x]

If weight is important, a thin steel will be lighter. That said, I did a build using a 20" proof and it is a laser and gets 3000fps with 140vld. If you are set on carbon in those lengths, I'd do proof 22".

 

[Mag_7s]

The PRC die "problem"

There are a number of people experiencing sizing issues with the PRC case. When designing a chamber, brass, and resize die there is no one size fits all. We want good hard case brass, but its harder to size. We dont want sloppy chambers either. I have experience with designing reamers with...

www.longrangehunting.com

Cliff notes: PRC cases (and others) are prone to expanding where brass is thick directly above the case head. Because of how thick the brass is here, it either is not sized down enough by dies or tends to spring back and/or easily expand again on subsequent shots. The clearance between SAAMI spec reamers and fired brass that has expanded at this location is tight, resulting in stiff bolt lift often accompanied by an audible "click" when lifting the bolt. Preferred solution is using a reamer with a larger dimension at the base of the case for more clearance. Lots of people also open up existing SAAMI chambers in this area.

Edit to add: @Badseed if you are handloading i would ask your smith if they have a reamer (like the AW2) with added clearance at the case web to combat clickers. If you're just shooting factory ammo it doesn't matter.

Interesting, thank you for sharing! There was a guy last week who reported pressure and heavy bolt lift out of his new 7prc using factory loads.The consensus was residual solvent left in the chamber during break in. Could this also be an inherent issue with the 7prc?

 

[wind gypsy]

Interesting, thank you for sharing! There was a guy last week who reported pressure and heavy bolt lift out of his new 7prc using factory loads.The consensus was residual solvent left in the chamber during break in. Could this also be an inherent issue with the 7prc?

It's a factor with all of the PRCs but typically does not show up until brass has expanded at the web from multiple firings.

 

[Oregonmuley]

In regards to CF wrapped barrels, I haven't seen one of the Benchmarks but they look like a well made barrel, also don't know how much they weigh compared to a like profile Proof or Bartlein. I think the Proof will be the lightest weight of the 3 due to the internal liner being a bit thinner overall versus the others. I have 2 CF builds with a Bartlein barrel and they are heavier but my smith preferred the Barts over the Proofs due to what has already been posted - some Proofs don't shoot as well.

I know my first Bart he said was one of the nicest barrels has had ever spun up - as far as the inside of the barrel. I will say the Bart CF wrap isn't nearly as "pretty" as the Proof or Benchmark of that matters

Lastly on 24" versus 22", I'd go no more than 22" for the proper balance - what stock/action will you be using?? A little muzzle heavy is good - too much isn't and will make the rifle feel out of balance which isn't great for shooting or carrying. Both mine are #4 contour Bart CF finished @ 22.5" in Proof stocks and balance is spot on.

Good luck on your build, be sure to keep us posted as it comes together.

 

[Badseed]

Thanks for the input. I did look at Bartlein CF early on but they are 7-8 months out for a new barrel. Their retailers only have 26” barrels in stock. Benchmark had equal recommendations from the dozen or so smiths I talked with. I need to do a little more research on them. I started with Proof because it seems like they are the name that comes up most often with CF barrel. Also, I will be reloading so this rifle and am already aware of the potential clicker issue and reamer options. Oddly enough some smiths say the AW2 reamer is just sloppy gun smithing and that a well chambered prc done to saami spec should not have clicker issues.


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[Wrench]

If you're heart set on carbon enjoy....if you want accuracy AND weight similar to the carbons....possibly even lighter, I'd go steel and have Dixon flute it with the x pattern. You'll get more predictable results and save money while still looking cool....or just a light taper if weight is the goal.

Most carbons I've been around or built are much pickier than steel.

 

[wind gypsy]

Oddly enough some smiths say the AW2 reamer is just sloppy gun smithing and that a well chambered prc done to saami spec should not have clicker issues.

Interesting take, calling AW sloppy.

When i was choosing between 300 PRC and WM Travis at TS just had the SAAMI reamer and didn't seem aware of any clicker issues. Not too long after there was a rokslide build for an action review in 6.5 prc chambered by them where @Travis Bertrand indicated they were using a reamer with more clearance. No idea if they got that reamer due to experience with function or based on demand.

 

[XLR]

Interesting take, calling AW sloppy.

When i was choosing between 300 PRC and WM Travis at TS just had the SAAMI reamer and didn't seem aware of any clicker issues. Not too long after there was a rokslide build for an action review in 6.5 prc chambered by them where @Travis Bertrand indicated they were using a reamer with more clearance. No idea if they got that reamer due to experience with function or based on demand.

Not to overtake this thread with a clicker issue but I think a lot of it also depends on the brass you are using and the resize die. If you have some nice and tight resize dies and an appropriately sized chamber you should be fine in my experience! I don't think it would hurt anything to run the AW reamer though besides maybe a tiny amount of brass life.

A lot of the comments above are pretty accurate and well said. My opinion of any barrel manufacturer is 95% of them are going to shoot really well, but the bad reports about proof is because they probably have 5x to 10x more carbon barrels in the wild so there are more cases. I have heard of bad barrels from almost every big name manufacturer out there so I wouldn't let that deter you from anyone. All of the bad experiences have also ended with the manufacturer taking care of them so that is also a great part about the custom rifle industry!

 

[Wrench]

I'd be willing to bet if guys getting clicks had strain gauges instead of chronographs....they wouldn't get clickers.

 

[wind gypsy]

Not to overtake this thread with a clicker issue but I think a lot of it also depends on the brass you are using and the resize die. If you have some nice and tight resize dies and an appropriately sized chamber you should be fine in my experience! I don't think it would hurt anything to run the AW reamer though besides maybe a tiny amount of brass life.

I'm curious what brass, die, reamer combo you've had good experience with and over how many firings? I think @Wrench made a good point too about pressure.

I only know from my limited experience and from lots of reading. My biggest clicker c-unt was a 300 norma. My dies sized the base of the case as much as 0.003" from fired dimension if i recall correctly but that didn't matter because once they'd expanded to be tight in the chamber once they'd be sticky in that chamber every round thereafter. At that point brass life is irrelevant, it might have 10 more firings in it but if its going to be a sticky **** every firing it's trash. Lapua brass supposedly does much better than norma resisting growth at the web in that cartridge.

 

[CCooper]

I went with a 22” Bart #13 carbon on my 6.5 PRC and have never wished I had gone longer.

 

[Badseed]

I went with a 22” Bart #13 carbon on my 6.5 PRC and have never wished I had gone longer.
View attachment 527661View attachment 527662

Thats awesome and looks like quite the shooter. Im assuming thats a hand load. What was the load data?


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