MudRunner2005
Well-Known Member
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500 Jeffery based wildcats
- Thread starter Swamplord
- Start date
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Who's your gunsmith?
Varminator 911
Well-Known Member
Maybe I'm all wet but I think phorwath is questioning the same thing. I'm asking is there enough steel all around that big fat cartridge using a 700 action to be safe? I'm pretty sure several gunsmiths that post here refuse to build around any cartridge fatter than the RUM size. It's the bolt, lugs, receiver, and barrel shank diameter in that action that is in question.
Someone correct me if I'm getting senile.
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The larger the inside diameter of the cartridge case, the greater the force that will be applied to the bolt face, and to the bolt lugs against the receiver. Force = Pressure X Area. Increase the cross-sectional area and the force will increase proportionally for any given pressure. The 0.621" outer diameter of the 500 Jeffery case, versus the 0.588" outer diameter for the .338 Lapua case, will generate approximately 12.5% greater force on the bolt lugs, given equal case pressures.
Expressed another way, to keep bolt lug force similar to the 338 Lapua case, you'll have to reduce 500 Jeffery case pressure 12.5% less than 338 Lapua case pressure.
There are gunsmiths that have posted on this Forum that refuse to chamber the smaller diameter 338 Lapua cartridge in a Remington 700 action because they've experienced steel yielding (deforming) where the bolt lugs contact the receiver with the 700 action. This yielding of the steel results in growing/increasing cartridge headspace. Doesn't mean you can't find someone that might be willing to build the 500 Jeffery-based wildcat on the Rem 700. It does mean that some will refuse to take on the risk of liability for chambering the 500 Jeffery case in a 700 action.
You may be asked to consider using a larger framed bolt action. A Weatherby Mark 5 action would probably be a better fit for this large diameter casing. I'm sure there are additional options, including expensive custom actions.
From Wikipedia:
"There have been a few rifles chambered in the 500 Jeffery including Jeffery, Heym, CZ-USA, and a few single shots including Ruger No.1, and the Butch Searcy & Co.. Mauser offers its Model 98 magnum in the caliber. Its "Elephant" model is offered in 500 Jeffery exclusively. In 2011, Sako began offering the caliber in its Model 85 "Safari" rifle using a new XL size action."
No mention of any commercial rifle manufacturer chambering the 500 Jeffery in a Rem 700-sized bolt action.
MudRunner2005
Well-Known Member
Swamp...You had any chance to work on my specs yet? Sorry, just anxious to see what it will look like! Bet it's gonna be wicked!
Mudrunner
I'll work it up when I get home tonight !
The Rem 700 was a consideration simply because I have a blued 300 RUM available to chop up,
it is definitely a point in discussion as I had the same questions on the integrity of it, Remington builds guns in 338 Lapua on their 700 and the big Jeff works on lower pressures than the hopped up 338 Lapua to begin with,
also the boltface will be less alteration from .534" to .575" versus the Lapua at .589"... I was told by several smiths it would work just fine so long as the pressures are maintained for the original cartridge.
My other (and original) option is to use a Sako M995 which already has the proper boltface.
I have two Sakos one in 7.82 Warbird and another in 30-378 WBY so either one will work just less aftermarket options which led me to the M700..
I welcome all input and especially concerns regarding safety..
I'll work it up when I get home tonight !
The Rem 700 was a consideration simply because I have a blued 300 RUM available to chop up,
it is definitely a point in discussion as I had the same questions on the integrity of it, Remington builds guns in 338 Lapua on their 700 and the big Jeff works on lower pressures than the hopped up 338 Lapua to begin with,
also the boltface will be less alteration from .534" to .575" versus the Lapua at .589"... I was told by several smiths it would work just fine so long as the pressures are maintained for the original cartridge.
My other (and original) option is to use a Sako M995 which already has the proper boltface.
I have two Sakos one in 7.82 Warbird and another in 30-378 WBY so either one will work just less aftermarket options which led me to the M700..
I welcome all input and especially concerns regarding safety..
MudRunner2005
Well-Known Member
LOL Sorry for the impatience. Today was a long slow boring day, so I had alot of free time at work to sit around twiddling thumbs. I won't bug you. Hahaha!
a comparison pic of my 6.5 Prometheus next to 270 WIN and 6.5 WSM
the case is the 300 Norma Magnum with a 6.5mm 140 gr Berger VLD , has not been fireformed yet which will give it a longer neck and shoulder pushed up to 35 degrees similar to the 6.5 WSM on the right in the pic.
the case is the 300 Norma Magnum with a 6.5mm 140 gr Berger VLD , has not been fireformed yet which will give it a longer neck and shoulder pushed up to 35 degrees similar to the 6.5 WSM on the right in the pic.
Attachments
barnesuser28
Well-Known Member
Wow! whats the neck thickness of that prometheus? You can see just how thick it is by looking at the outside edge of the bullet and outside edge of the neck.
MudRunner2005
Well-Known Member
Holy crap I just noticed that! I bet he can get 100 reloads per brass! Hahaha!
barnesuser28
Well-Known Member
Oh ok, haha that makes sense, i was trying to figure out how you would have any spring back in the neck to let the bullet release. On your 338, i am assuming that you are not going to neck turn? If not you would have approx .022" neck thickness?
MontanaRifleman
Well-Known Member
Swamplord, do you have dimension specs for the 300 Norma Mag? I'm looking at it for a possible project.
I have the dimensions for my 7.62 PRO that you can go off in the attached pics...
I have the "PRO" (Precision Rifled Ordnance ) series of wildcats I have been working on for my Sako M995 switchbarrel rifle and have 2 wildcats based on the 300 Norma Mag case
6.5 Prometheus
7.62 PRO
based on the 338 Norma Mag case I have the
338 PRO
375 PRO
416 PRO
458 PRO
There will be 7 barrels total for the project based on a Sako M995 and a KRG Whiskey 3 chassis, topped off with a Vortex PST 4-16X50 EBRMOA scope
the 1st barrel is already on the finished rifle and is chambered in 338 Norma Magnum
I also still have the original bbl the rifle came with chambered in 7.82 Warbird and can use it if need be, making 8 total barrels in one rifle system !
The design of the cartridges and chambers was specifically intended to be run in rifles equipped with AICS cip length detachable magazines . the throat/leade is set so the bullets do not protrude below the neck to enhance powder capacity, at the same time the neck was made longer and shoulder pushed up to 35 degrees but top of body was not increased in diameter but kept at .570", which I found feeds and cycles from the mags much better than a blown out AI 40 degree version which occasionally tends to bind up and jam in the mag due to the steeper shoulder and slightly larger top of body diameter without providing a usable increase in powder capacity !
You will notice the neck lengths are longer in the 6.5 and 7.62, the longer necks are for the cartridges that are more susceptible to faster throat erosion
the 338, 375 and 416 share the same .342" neck length and the 458 has a .375" long neck to hold the long heavy bullets, which is important in a hard recoiling dangerous game rifle.
If the Rem 700 will not work out for my 500 Jeffery based wildcats, they will be built on a similar platform off the Sako M995 currently in 30-378 WBY, I will just have to modify the ridges in the mags to accept the wider case body, the cartridge oal will remain the same for all reg. hunting bullets up to 300 grs. and 330 gr- 350 gr. long high bc bullets will be run single shot for long range shooting.
I designed and own all the reamers and they are proprietary, made for me by PT&G
Dave Kiff is a fantastic and very knowledgable gentleman who has assisted me in the dimensions and developement of my reamers, without his help none of these wildcats would be here today ! Neil Jones is making me the dies, with all the crazyness going on he is super busy and ETA is not known at the moment...
........
I have the "PRO" (Precision Rifled Ordnance ) series of wildcats I have been working on for my Sako M995 switchbarrel rifle and have 2 wildcats based on the 300 Norma Mag case
6.5 Prometheus
7.62 PRO
based on the 338 Norma Mag case I have the
338 PRO
375 PRO
416 PRO
458 PRO
There will be 7 barrels total for the project based on a Sako M995 and a KRG Whiskey 3 chassis, topped off with a Vortex PST 4-16X50 EBRMOA scope
the 1st barrel is already on the finished rifle and is chambered in 338 Norma Magnum
I also still have the original bbl the rifle came with chambered in 7.82 Warbird and can use it if need be, making 8 total barrels in one rifle system !
The design of the cartridges and chambers was specifically intended to be run in rifles equipped with AICS cip length detachable magazines . the throat/leade is set so the bullets do not protrude below the neck to enhance powder capacity, at the same time the neck was made longer and shoulder pushed up to 35 degrees but top of body was not increased in diameter but kept at .570", which I found feeds and cycles from the mags much better than a blown out AI 40 degree version which occasionally tends to bind up and jam in the mag due to the steeper shoulder and slightly larger top of body diameter without providing a usable increase in powder capacity !
You will notice the neck lengths are longer in the 6.5 and 7.62, the longer necks are for the cartridges that are more susceptible to faster throat erosion
the 338, 375 and 416 share the same .342" neck length and the 458 has a .375" long neck to hold the long heavy bullets, which is important in a hard recoiling dangerous game rifle.
If the Rem 700 will not work out for my 500 Jeffery based wildcats, they will be built on a similar platform off the Sako M995 currently in 30-378 WBY, I will just have to modify the ridges in the mags to accept the wider case body, the cartridge oal will remain the same for all reg. hunting bullets up to 300 grs. and 330 gr- 350 gr. long high bc bullets will be run single shot for long range shooting.
I designed and own all the reamers and they are proprietary, made for me by PT&G
Dave Kiff is a fantastic and very knowledgable gentleman who has assisted me in the dimensions and developement of my reamers, without his help none of these wildcats would be here today ! Neil Jones is making me the dies, with all the crazyness going on he is super busy and ETA is not known at the moment...
........
