Gunsmithing 16.5 " barrel questions

[sawman556]

I want to put a new 16.5" .308 barrel on my Stiller TAC 30 action. I'm looking at a Bartlein #9 heavy varmint.

http://www.grizzly.com/products/-308-5R-...0-Barrel/T10560

A)1.250 B)5.000 C).900 D) 28" 7.45#

Caliber .308 5R
Twist 1-10
Length: 30" Finished
Contour: 1.250" x 5" Taper to .900
Bore/Groove: .300/.308

So my questions are:

Can a couple inches be cut off the "B" end and have it chambered and threaded? Then cut/crown/thread the muzzle end to 16.5"?

Is a 1-10 a good twist-rate for 168's and 175's out to 800 yards? Most shooting will be in the 300-600yd range.

I also want to have this barrel helical fluted. At 7.5lbs. to start with, any idea of the weight it will be when it is cut and fluted?

Any idea what the barrel OD will be at the muzzle?

I also want to pin a thicker recoil lug like the Badger to my action. Thread the muzzle 5/8-24 and have a brake contoured/timed/ID'ed and thread protector.

Thoughts?

Any of the pro smiths want to PM me a price on labor for this? It does not need to be finished.

Thanks for your help.

 

[Edds]

Re: 16.5 " barrel questions

Muzzle diameter will be 1.045".

 

[sawman556]

Re: 16.5 " barrel questions

Thank you sir for your fine math skills!

 

[lonely_wolf]

Re: 16.5 " barrel questions

You can cut the B end. My smith said he prefers to keep the cylinder (B end) at least two inches long. It is easier for him to set the barrel up in his machines.

You will find different answers about twist rates. I don’t think you can go wrong with a 1/10 on a 308. It is probably the most popular. I have a 1/10 20" that shoots 168s and 178s fine.
I wouldn’t have the barrel fluted. It costs more and the weight savings are small. You’ve already chosen a heavy barrel, if weight is a concern than a lighter contour would be more effective than fluting.

Thicker lugs are fine. I went with a .250" as it was recommended the most by those I spoke with.

Thread the barrel if you want it threaded. Make sure you choose a thread pitch that will work for whatever you have planned. Some are more common than others. 5/8-24” is a good choice.

Ask for a USMC crown or other recessed styled crown.

+1 on short and fat barrels on bolt guns.

 

[JJones75]

Re: 16.5 " barrel questions

After shooting heavy ass truck axels for years my last 308 working gun has a 16.5" Palma conture. 1.5" strait shank in front of recoil lug.

This gun will shoot sub MOA 10 shot groups at 500 consistantly both with and without a can. My suppressor is close to 30 oz mand while their is a POI differance with and without it , it is consistant and repeatable.

I seriously dont think that a barrel needs to be that fuckin stiff!!

 

[sawman556]

Re: 16.5 " barrel questions

Thanks for the replies. I'm just thinking out loud with this thing. Since this is really just a toy I kind of wanted to make it look wicked.

 

[SmokyJoe]

Re: 16.5 " barrel questions

Here is a link to a download for a
Contoured Barrel Weight Calculation Program

The default density in the program is .276 lb/ci (for 416 SS)
IIRC, the density for chrome moly is .283 lb/ci

It will also calc for flutes if you know the dimensions. If you can addify the length of helical flutes on a contour you are a better man than me. (String rolled on a 1" dowel??)

I get ~4.645 lbs without flutes for SS.

 

[JJones75]

Re: 16.5 " barrel questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sawman556</div><div class="ubbcode-body">Thanks for the replies. I'm just thinking out loud with this thing. Since this is really just a toy I kind of wanted to make it look wicked.
</div></div>

No better reason to get somthing than just wanting it!!

I have a buddy building a 6mmBR with a 22" full bull barrel so he can radial flute it .125" wide "flutes" and "lands" by .125" deep , his idea is massive surface area and because HE like the way it looks

 

[lonely_wolf]

Re: 16.5 " barrel questions

@D.Draig: Cool link. Thanks.

 

[sawman556]

Re: 16.5 " barrel questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lonely_Wolf</div><div class="ubbcode-body">@D.Draig: Cool link. Thanks. </div></div>

+1

Thanks my friends.

 

[A Gunsmith]

Re: 16.5 " barrel questions

Its post like this that makes me want to Blue print my Remington 700, and inlet and bed a stock for it. this gyn truely sucked out of the box. and to respond to this post, I would just order a blank with the flutes in it, snd to all who replied great answers

 

[SmokyJoe]

Re: 16.5 " barrel questions

Sawman,

Sounds like a great concept. I'll be looking forward to seeing how it comes together.
Are you targeting a specific weight for the finished rifle?

 

[sr15match]

Re: 16.5 " barrel questions

I say go for the shorty truck axle build!!

I had Mike Bush put together a 16.5" 223rem for my wife using a Brux 1-8" twist M24 contour barrel. I haven't been able to shoot it yet but it balances awesome in a McM A5. I think it's 10.8 lbs or so minus the scope.

Build it and you will shoot!!!!!

 

[sawman556]

Re: 16.5 " barrel questions

This will be replacing a 20" varmint/Sendero contour. It's going to go on my KRG Whiskey 3 chassis. It currently weighs in at 15lbs. fully decked out without ammo. My hope was with the fluting and cutting a couple inches off the chamber end that I would come close to staying in the same weight class.

 

[2156SMK]

Re: 16.5 " barrel questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sawman556</div><div class="ubbcode-body">This will be replacing a 20" varmint/Sendero contour. It's going to go on my KRG Whiskey 3 chassis. It currently weighs in at 15lbs. fully decked out without ammo. My hope was with the fluting and cutting a couple inches off the chamber end that I would come close to staying in the same weight class. </div></div>

That 16.5" truck axle is gonna be about 1.5-2lbs heavier than your 20" rem varmint barrel.

 

[sawman556]

Re: 16.5 " barrel questions

I can handle it being a pound or two heavier. What would a 24" M24 weigh with a McM A5 sniper-fill with everything but ammo?

 

[sawman556]

Re: 16.5 " barrel questions

Thinking out loud. Would something like this be possible???

 

[Pusher591]

Re: 16.5 " barrel questions

Start off by getting a shorter blank, why buy a 30" blank to cut it in half. Order you a 22" blank and it will still be plenty thick at the muzzle and should help a little with weight.

 

[sawman556]

Re: 16.5 " barrel questions

Will buying a shorter blank be cheaper? And where can I order one that won't take months to get?

 

[2156SMK]

Re: 16.5 " barrel questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sawman556</div><div class="ubbcode-body">Thinking out loud. Would something like this be possible???

</div></div>

With proper funding, anything is possible.

 

[2156SMK]

Re: 16.5 " barrel questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sawman556</div><div class="ubbcode-body">Will buying a shorter blank be cheaper? And where can I order one that won't take months to get? </div></div>

Cheaper to manufacture?
Yes.

Cheaper for the customer?
Most likely not as it would be custom.

In stock anywhere, seriously doubt it.

It's always faster/cheaper to get a full length blank because you can find them off-the-shelf.

Now, if you are doing a production run and want to order hundreds of barrels, the price DOES go down as you make the blanks shorter.
I used to order 20 blanks at a time for making AR barrels and I got a better price on 17" long blanks than I did on 21" long blanks.