I have a 300 weatherby accumark that I want to rebarrel with a bartlein barrel. It will be a 30" tube with a 10 or 9.5 twist. The question is the gunsmith ask me what reamer that I wanted to use. He said there is a standard with the freebore, short throat and no throat. I will be shooting the 230 bergers and I feel that I am loosing accuracy because of all the freebore. The short throat sounds good but do you still use published load data or is that for freebore weatherbys. Thanks Anthony
300 weatherby rebarrel question
- Thread starter TonyQ
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sable tireur
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TonyQ,
Are you considering a single shot or magazine fed rifle?
The fixed magazine or detachable box magazine will determine the maximum length of your cartridge. Your load development will determine the cartridge length when you achieve your accuracy load with bullet seating.
You could start with the 'short throat' reamer as a middle ground where you can reach the lands if you want to or have your gunsmith extend the throat and freebore to allow you to seat the bullet further out.
Starting loads from any of the published sources should be safe. Then simply work your way up the scale as you would normally, searching for the accuracy nodes, watching for signs of pressure.
Regards.
Are you considering a single shot or magazine fed rifle?
The fixed magazine or detachable box magazine will determine the maximum length of your cartridge. Your load development will determine the cartridge length when you achieve your accuracy load with bullet seating.
You could start with the 'short throat' reamer as a middle ground where you can reach the lands if you want to or have your gunsmith extend the throat and freebore to allow you to seat the bullet further out.
Starting loads from any of the published sources should be safe. Then simply work your way up the scale as you would normally, searching for the accuracy nodes, watching for signs of pressure.
Regards.
elkaholic
Well-Known Member
That is a good question? I would think it might depend on which manual you use, but I don't know that for sure. I would have to believe that MOST manuals would list the factory chambering (throat) I would start a couple of grains lower than what the manual says if there is any doubt because the Weatherby throat is pretty long and a max load with a short throat could cause problems! I know that many customs, which shoot the Weatherby case, use a shorter throat, for the accuracy reasons you mentioned.
turkn8r1
Well-Known Member
First off why not go with a transitional twist one of Bartlein's specialties. Definately go with 5R rifling. I am doing the same thing with a 30-378 Mark V stainless. I'm having mine short throated so I can get to the lands while not exceeding the capability of the magazine. My intention is to use a 15 thousanth set back from the lands with conventional bullets and touch the lands with G S Custom drive band bullets. I will also be working up the load from no more than mid range. Hope this helps.
I decided to use it as a single shot and a short throat. It will be a 30" barrel so I am hoping to get 3050fps with the 230gr bergers with RL33. I will start from the min and work up. Also going to have it bedded and have the trigger worked on while he is in there. I will see how it goes now the waiting it the tough part.
wwbrown
Well-Known Member
Another option would be to contact Dave Kiff at PT&G and ask him about his bore rider option on a new reamer for the 300 Weatherby. The bore rider is very similar to what Shawn Carlock uses on his Edge +P a longer transition between the normal throat diameter and the bore diameter.
wwbrown
Well-Known Member
Please post what he says as I would like to learn more about the Dave's new design because I think it may have a lot of options.
wade
wade
wwbrown
Well-Known Member
The bore rider reamer from Kiff and the bore rider bullet are not related. I know of two examples of the reamers being used like I said the 338 Edge +P from Carlock and for match winning short range benchrest rig shooting the 6 Dasher both of them are for non-banded bullets just regular bullets give. Kiff a call.
I would be interested in learning about a bore rider reamer for conventional bullets too.
It sounds like someone may have found a different way to describe freebore.
I recently had a custom reamer made for a 30 caliber wildcat. The capacity of my cartridge is close to a 300 Weatherby. I also intend to use Berger 215 or 230 gr bullets. I just checked the SAAMI spec for a 300 Weatherby chamber, my chamber has .015" more freebore than the Weatherby.
elkaholic
Well-Known Member
The bore rider reamer tapers the rifling for a distance beyond the normal throat which reduces initial pressure. I think kiff kind of &^%*&^ (borrowed) Carlocks design...........Rich
So it is just a smaller throat angle? What is the throat angle? I've seen SAAMI chamber specs on various cartridges that range from .5° to 3°. The difference between a half of a degree and 3 degrees is about 3/8 of an inch.
elkaholic
Well-Known Member
I don't know exactly what the angle is, but in some cases, it is a "stepped" design which Shawn has a patent on...........Rich
