Best LR .30 caliber on .473 bolt face

FEENIX,

I will go a step further and say ignorance is a factor, also. When I was a new loader I read about cream of wheat for forming. I weighed out the powder charge and then weighed out the cream of wheat to fill the case as though it were a bullet, but with no bullet. The brass swelled on the belt .170". That is not .017". Of course the bolt had to be beat open with a rubber hammer. The chamber was bulged a few thousands. What I learned was one doesn't load the cream of wheat and wait a week before one fires it.
WOW, that's interesting. Thanks for sharing.
 
FEENIX,

I will go a step further and say ignorance is a factor, also. When I was a new loader I read about cream of wheat for forming. I weighed out the powder charge and then weighed out the cream of wheat to fill the case as though it were a bullet, but with no bullet. The brass swelled on the belt .170". That is not .017". Of course the bolt had to be beat open with a rubber hammer. The chamber was bulged a few thousands. What I learned was one doesn't load the cream of wheat and wait a week before one fires it.
Wow, im glad you shared that. I once just filled a 22-250 case with retumbo and packed paper in the top, thinking it would be a cool flame. Instead it sounded liked I dumped a salt shaker across my back yard. Powder didn't ignite lol Apparently back pressure is necessary 😅
 
My cousin is looking to rebarrel a Rem 721 long action and is wanting the best .30 caliber he can put on this action. Not looking to change the bolt face. He is looking to match or exceed 300 Win Mag if possible. Just share facts and your experiences please. Please don't make this a ,,,,,, contest.
.300 RUM
 
One I wanted to consider is a Weatherby 30-6.5 RPM wildcat. It is basically a long version of the 284 Win case and takes advantage of the wider case but fits the standard bolt face and action like the 30-06. PTG has a reamer for this. Cases can easily be formed using Weatherby 6.5 RPM cases and necking them up to 30 caliber. Playing around in QuickLoad it should get somewhere between 3060 and 3100 FPS with a 180 gr Accubond and a 26 in barrel depending on the powder. Dropping to a 24 in barrel reduced the velocity by 30 FPS or more.
 
Reading trough all this I tend to agree about 30-6.5RPM is best choice.
But the 30gibbs both seams like a cool name and historical it is interesting.
Anyways custom reamers are not that expensice so why not a 30gibbs improved?
Blow out the case walls a little for additional powder capacity and less bolt trust?
Most productionlines try to minimize tooling so I guess anyone making 308brass use same materials and tooling as for the 30-06 so I gave no doubt 30-06 can be loaded to 308 pressure as long the bolt trust is not increased.
 
The only issue I can see with the RPM case is possible modification on the feed rails or installation of a new magbox or detachable mag system. With an AI and a pushfeed action you probably wouldn't have to do either.
 
The only issue I can see with the RPM case is possible modification on the feed rails or installation of a new magbox or detachable mag system. With an AI and a pushfeed action you probably wouldn't have to do either.
Feed rails are same width on long action std or magnum. Good there
 
My understanding is on older actions the 30-06 feed rails were more narrow than on magnums. One way to find out.
 
One I wanted to consider is a Weatherby 30-6.5 RPM wildcat. It is basically a long version of the 284 Win case and takes advantage of the wider case but fits the standard bolt face and action like the 30-06. PTG has a reamer for this. Cases can easily be formed using Weatherby 6.5 RPM cases and necking them up to 30 caliber. Playing around in QuickLoad it should get somewhere between 3060 and 3100 FPS with a 180 gr Accubond and a 26 in barrel depending on the powder. Dropping to a 24 in barrel reduced the velocity by 30 FPS or more.
So reinventing the .300 Win Mag to use a .30-06 bolt.
 
Actually if you load to the pressure the cartridge was intended to be used at you use the 1 in 4 factor which come out to 2.25% increase in velocity and 65FPS more velocity then the standard velocity.Very few improved cartridges if loaded to equal pressures are much of an improvement.How ever most folks who load improved cartridge load until they can barely open the bolt,back off a grain and call it good to go with out having any idea of the actually pressure as they have no access to the strain gauges needed for this.Look a PO Ackleys books and some of the loads he used ,velocities claimed with no access to a chrono.SCARY!!!!!
I agree with you on the gains when we keep the pressures equal, P O Ackley did give instructions on how to build a early chronograph in his handbook.
 
Warning! This thread is more than 4 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top