Good
Well-Known Member
Hey guys, is there a short action rifle action that can take the bolt face of the 505 Gibbs (408 Chey-Tac parent) with a .640 rim?
Short Action Big Bolt Face?
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J E Custom
Well-Known Member
Most short actions are designed for Magnum bolt faces smaller than .590. the bolt will have to be larger to handle the 505 Gibbs case head and normally it will be a long action.
Some of the custom action makers may make one but i doubt it. There are some good actions designed for this use that have much larger bolts that will accommodate this cartridge and I would recommend their use.
Bolt Actions for the 50 BMG have a .660 rim diameter that it has to deal with, so There should not be a problem finding an action. If you are looking to shorten a 505 case, there are other cases with smaller rim diameters that
will do that and may fit into a short action.
J E CUSTOM
Some of the custom action makers may make one but i doubt it. There are some good actions designed for this use that have much larger bolts that will accommodate this cartridge and I would recommend their use.
Bolt Actions for the 50 BMG have a .660 rim diameter that it has to deal with, so There should not be a problem finding an action. If you are looking to shorten a 505 case, there are other cases with smaller rim diameters that
will do that and may fit into a short action.
J E CUSTOM
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Good
Well-Known Member
So, I'm not thinking shoot a 408 CT from a short action, but rather wildcat to design a short and fat, like the .50 fat mac, but designed to shoot 300g .338 bullets from an every day short action magazine without being too far in the case, and 250s without being too far out... I haven't got into design, but just wondering if a standard short action is out there that would fit the bill.
I have wondered about Ackley improving the Lazzeroni 8.59 Galaxy and designing a reamer around specific measurements to shoot heavies from the magazine for quite a while, but the brass is impossible to get so I thought instead of the 30-378 bolt face size, why not look at the 408 CT size and build from there. Is it possible?
I have wondered about Ackley improving the Lazzeroni 8.59 Galaxy and designing a reamer around specific measurements to shoot heavies from the magazine for quite a while, but the brass is impossible to get so I thought instead of the 30-378 bolt face size, why not look at the 408 CT size and build from there. Is it possible?
J E Custom
Well-Known Member
When I build a rifle on a 378 family of cartridges or a Lapua/Rigby I always use a Weatherby Mark 5 action because of the bolt size and the bolt face. It can be opened up to .600 +.
I have built several wildcats based on the 378 case that have almost equaled the CT. It held 144 grains of powder. I am also building a 358 RUM that should have lots of potential.
If you are looking for a short action wildcat, the 325 WSM is about the limit for short actions but it can be Improved and can add 8 to 10 grains of powder capacity. The problem is shooting 300 grain bullets requires lots of slow burning powder and the short actions just don't have the powder capacity.
I designed the 338 Texan, and it holds an average of 119 grains of powder and the best velocity it was able to achieve was 3155 ft/sec with a 300 grain 338 bullet. but it requires a long action Mark 5.
Where you wan't to start is around 100 grains of powder and the short actions will only hold 65 to 75 grains when they are wild cat's.
Nothing is impossible, but what you are thinking is very close to it.
J E CUSTOM
Interesting concept Good.
What sort of velocity are you hoping to get with a 300 gr bullet? I understand the challenge of creating and using your own wildcat. Just looked Galaxy brass is available from several sources.
What sort of velocity are you hoping to get with a 300 gr bullet? I understand the challenge of creating and using your own wildcat. Just looked Galaxy brass is available from several sources.
Good
Well-Known Member
I can't find that brass. My google-fu must be challenged. 
The goal would be to maximize the bolt face. Similar to what Rich has done with the Sherman Short mags. Without digging into the design, It seems like he has extracted as much performance as you can from the .540 face. Why not do the same thing (or similar) with a bigger bolt face For more powder and see where performance winds up?
The parameters are just: mag feed keeping it true short action and capable to shoot 300 and 250 grainers without much issue either way.
It would be fun to talk to Shawn Carlock and Rich and JE, and guys who have dealt with it, about freebore. Then, when measurements are fairly finalized we can figure powder capacity and performance from there.
I'm thinking strict 40* shoulder and as straight sidewalls as practical, but everything is a compromise. Those are my thoughts.
The goal would be to maximize the bolt face. Similar to what Rich has done with the Sherman Short mags. Without digging into the design, It seems like he has extracted as much performance as you can from the .540 face. Why not do the same thing (or similar) with a bigger bolt face For more powder and see where performance winds up?
The parameters are just: mag feed keeping it true short action and capable to shoot 300 and 250 grainers without much issue either way.
It would be fun to talk to Shawn Carlock and Rich and JE, and guys who have dealt with it, about freebore. Then, when measurements are fairly finalized we can figure powder capacity and performance from there.
I'm thinking strict 40* shoulder and as straight sidewalls as practical, but everything is a compromise. Those are my thoughts.
adam32
Well-Known Member
It's been done, I believe Pierce is coming out with a short action that will accept the Cheytac bolt face.
Danny1788
Well-Known Member
I believe pierce is working on a short magnum action with the CT bolt face for some Wildcat rounds. Its not a Rem700 clone and would require special stock inletting. Call pierce engineering and see what they have to say.
Is a 338 nm close to this or is it a med action.Mine looks short next to my 340 wby.I went and looked at them,guess not because bullet is so long on NM.The 325 is a pip squeek next to it,doesnt compare in field performance.Shot quite alot with my 325wsm
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Good
Well-Known Member
So here's a comparison of some long action rounds. L->R 300RUM, 338 Tejas, 338 Lapua, 375 Ruger
the mighty Lapua is shorter than the RUM and Tejas. My thinking is go girth instead of length like Weatherby and RUM/Edge. It's still going to need to be shorter than the NM.
Danny1788
Well-Known Member
Look up SWAMPLORD he is the one designing the short CT bolt face wild cats
freddiej
Well-Known Member
okay, if I am reading right you want a wildcat short action in 0.338" . why not start with the 404 Jefferey's case and shorten it and neck it down. it's the parent case of the WSM's and WSSM's. readily available cases, bolt faces, and making a 30-06 length or 308 length case/action combo should be easy. the 30-06 case length has lots of potential.
BoatTail
Well-Known Member
What about a 338 - 28 Nosler Wildcat? I believe some have had them built.
