Rebarreling Help needed

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Lil-Rokslider
Joined
Dec 8, 2019
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209
Looking to get a 300 wsm rebarreled. I've got a lot of questions I'm going to try and fit in this one thread.

I want to set this up to run the Berger 215's as fast as possible in a Tikka action w/long bolt stop. Have the HCA mag to run 3.380 COAL which is more than enough.

What's the general consensus on how deep to seat bullets? I've seen two different thoughts:
The bearing surface 1 bullet diameter deep, which gives a 3.127 COAL
Base of the bullet at the neck/shoulder junction, which gives 3.262 COAL and only 0.173 of the bearing surface in the neck.

As fast as possible may be the wrong way to look at it, more like as accurate as possible at the highest node. Just don't want to handicap myself especially getting to spec the barrel.

Next is assuming I pick one of the options above how does that affect the freebore on the barrel? Should I load dummy rounds and send those to the smith, or is there a mathematical way to determine what freebore should be?

I've heard of the +P from Defensive Edge, anyone familiar with that? If the barrel is properly throated does the +P still affect anything (I'm thinking it does since it affects the pressure?).
If I am running a full or compressed charge already would the +P help? (I think not since there would be no room for more powder anyways?)

Hope is to run a 24" barrel and push the 215's at 3000 fps. Am I foolish to try and eek that out of a 300 wsm and should I just go PRC or Nosler? If jumping up cartridges I would prefer the Nosler, but not sure about COAL with that though. Looks like Mountain Tactical has bottom metal that can run up to a 3.600 COAL.

I already have reloading components for the 300 wsm so that's a big plus though.
 

Marble

WKR
Joined
May 29, 2019
Messages
3,251
Just my thoughts and opinions...

My build would be based more on the quality of the components and work being performed. Meaning, I'm going to pick one of the manufacturers the Smith likes to work with and that I am comfortable with.

I can reload and make almost anything work, so I won't get caught up in the throat, seating depth etc. It's kind of putting the cart in front of the horse. With these custom barrels, it's pretty dang rare for them to shoot really good.

You can, and I have, ask for a shallower throat and tell the Smith you want a gun chambered with a particular bullet in mind. That bullet can be seated from up to touching the lands to .050 off, if that's the most accurate load, and still fit in a standard magazine box.

I wouldn't worry too much about speed as you're probably talking 50 fps +/-. At distance that won't make a big difference.

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Harvey_NW

WKR
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Feb 13, 2019
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The way I interpret is ideally the max COAL/CBTO should be at least a calibers depth of bearing surface seated into the neck, and some consider optimum minimum to be the bottom edge of the bearing surface at the neck/shoulder junction.

From there it's my understanding you kind of collaborate your own perfect dimensions based on how much jump you or your setup is known to like, how hard you want to push your load, expected barrel life, etc., if there isn't a reamer with throating dimensions built in that fits the bill. I've always been told sending a dummy round is the best option.

As far as the +P throating, I have no personal experience but from what I have read you are correct, if you're already maximizing the potential of the cartridge and don't have any more room, it won't be any additional help.
 

B23

WKR
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What powder are you looking to use with those 215's in your 300 WSM?
 
OP
M

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Lil-Rokslider
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Dec 8, 2019
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209
Thanks everyone so far! I do need to keep checking myself, and try not to get hung up on maxing numbers, 50 fps is negligible for sure. Just figured if I know the bullet I want to run and am paying for a custom barrel might as well try and optimize it.

With the stock barrel currently I’m at 3.095 COAL with case pretty dang full, so sounds like I may not pick up much noticeable difference following the min .308 bearing surface deep. Just didn’t want to shell out the $$ and end up having to stuff the bullet.

Currently pretty flush on RL26, H1000, and H4350. Loading RL26 for it right now and that would be my first go through the new barrel.
 

Wrench

WKR
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You can seat a 215 deeper and it'll still fly. If you throat it for the longest bullet and there's no love for it with your recipes....you have a big jump to work with that's only going to get bigger as it burns in.

I personally would eat some of my case capacity and be glad I had a plan B option given the availability of components.
 

Marble

WKR
Joined
May 29, 2019
Messages
3,251
Thanks everyone so far! I do need to keep checking myself, and try not to get hung up on maxing numbers, 50 fps is negligible for sure. Just figured if I know the bullet I want to run and am paying for a custom barrel might as well try and optimize it.

With the stock barrel currently I’m at 3.095 COAL with case pretty dang full, so sounds like I may not pick up much noticeable difference following the min .308 bearing surface deep. Just didn’t want to shell out the $$ and end up having to stuff the bullet.

Currently pretty flush on RL26, H1000, and H4350. Loading RL26 for it right now and that would be my first go through the new barrel.

Why don't you fill up one of your shells to the bottom of the neck and see what that actual number is? You may be worrying about something that doesn't need to be worried about. Meaning, even one full grain above max may not even be enough to be an issue?

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OP
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Megalodon

Lil-Rokslider
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Dec 8, 2019
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209
Why don't you fill up one of your shells to the bottom of the neck and see what that actual number is? You may be worrying about something that doesn't need to be worried about. Meaning, even one full grain above max may not even be enough to be an issue?

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I’m on board, what you’re saying is very pragmatic, but my thinking is if I’m spending $800 plus gunsmithing I might as well optimize it. Even if it is only one grain more powder why not, it won’t cost any more.
 
Joined
Mar 6, 2016
Messages
351
I am currently in the same exact situation, 300WSM tikka barrel on order from McGowan. I'd like to shot 200s and they suggested sending in a few dummy rounds to make sure everything works out.
 

jjjones7

FNG
Joined
Mar 26, 2022
Messages
82
I like your thinking there. I’m currently running a 300WSM in a sako 85 short which limits me to a 2.905 COAL. I cut my barrel down to 21” to run my omega 300 and I’m running 200 grain ELD-X at 2850 using IMR 7828SSC with no pressure signs. If you do try to push it do yourself a big favor and buy the Norma Brass. They’re damn proud of it but it is hands down the best brass I’ve ran.
 
Joined
Mar 6, 2016
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A fellow slider sold me some Nosler brass which is apparently Norma brass that has been sorted. Getting pretty excited about those numbers you mentioned there
 

jjjones7

FNG
Joined
Mar 26, 2022
Messages
82
A fellow slider sold me some Nosler brass which is apparently Norma brass that has been sorted. Getting pretty excited about those numbers you mentioned there
Some of the nosler I suspect is some definitely isn’t. If it has that nice orangish tint to it you should be GTG
 
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