500 Jeffery based wildcats

Just give PT&G a call and one of the gals can e-mail you the reamer spec for a 300 Norma. Fast and easy!!

Thanks Rhian, I did talk to them a couple of days ago. I'm looking for case specs, not the reamer specs. Ammo Guide has specs for the 338 Norma case and I'm guessing the 300 is very similar. I'm curious as to the shoulder diameter and length, shoulder angle, shoulder/neck length and case length. I think I have a good idea of most of that but it would be nice to know for sure.
 
Swamplord, that is a cool system you have there. Looking forward to pics.

On the feasibility of using the 700 for the 500 Jeff cartridges, it brought back to memory some discussions about the Lapua in the the 700.

Do a google on 338 Lapua bolt thrust 700

Here is an interesting exchange with Jerry Stiller

338 Lapua and lug sheer - Sniper's Hide Forums

338 Lapua in Rem 700 Bolt Thrust Question...

Here's Kirby Allen's view post # 27

http://www.longrangehunting.com/forums/f17/howa-338-edge-69303/index4.html

Dan Lija's

Lilja Precision Rifle Barrels - Articles: 378 Weatherby Cases in the Remington 700 Action?

Lilja Precision Rifle Barrels - Articles: A Look at Bolt Lug Strength
 
Swamplord, how much faster would you say the 7.62 Pro is over a .300 RUM both with same weight bullets? BTW any updates on the .375 or .338-500 Jeff?
 
the 7.62 PRO was not intended to beat the 300 RUM in velocity but to equate the performance and have the ability to run high bc heavy bullets through 5 round AICS cip detachable mags...

it turns out with the ability to seat the 200 + grn bullets way out to max fit the AICS mags , there is actually slightly more powder capacity with much better brass than the Rem 300 RUM.
..
also with a shorter fatter case and a 35 degree shoulder and a much longer than usual neck for 30 cals. I am hoping to extend throat/barrel life accuracy over the 300 RUM with similar velocities in all bullet weights, in the event of extreme high bc 250 + gr bullets this case will excel even more over the 300 RUM without cartridge OAL limitations and having to run single shot...........

it's all theory at this point and will have to be proven with a lot of loading and range time...
rifle is completed and ready to go but no dies yet, still waiting !!!!!!

my velocity goal is 3300 fps with 210 gr bullets in a 32" 5R 10 twist Rock Creek barrel give or take a few fps + or - ....
 
BTW any updates on the .375 or .338-500 Jeff?


As with any project there will be design changes made at times to make a product better, either with hard data or theoretically....

I made some changes I felt were necessary...

I got my hands on a batch of the new Jamison 500 Jeffery brass and also some of the 500 AHR brass.. the 500 AHR was designed by Dr. Ken Howell as an improvement over the 500 Jeffery
and the brass is made by Bertram ( 500 AHR = American Hunting Rifle)

the case head/ web was beefed up to better handle higher pressures and the entire length of the body was also slightly thickened, the case is longer then the Jeff and the rim is larger in diameter for better extraction, my entire batch of brass was measured repeatedly and every single case had an identical rim diameter of .585", all other dimensions were repeated satisfactorily, it was very uniform brass. With the rim diameter I do not need to alter the bolt on my Sako M995 which is set up for my 338 Norma Mag based wildcats and they measure exactly the same at .585", hells yeah !!!

I suspect the case head treatment is the same application used by Bertram for Mr. Carlocks 338 Edge brass, which is a very good thing, the original 500 jeffery brass was not designed for todays higher pressures.....

I then cut in half the 500 AHR, 500 Jeffery (original Bertram brass) and the new Jamison 500 Jeffery brass to see how they compare to each other.....

The 500 AHR brass shows a definite improvement over the original Jeff and so does the Jamison stuff, a win win situation for me, I can certainly load my 338 Wolverine and 375 Mjolnir to the same pressures as the 378 Wby and 338 Lapua, with careful loading and gradual workup of course,

I made the decision to run my wildcats with the 500 AHR brass as it has a slightly larger rim and improved case head which will offer me higher velocities and longer brass life coupled with better extraction.... the cases fit the bolt perfectly and also work on the Jamison brass which has a rim diameter of .573" but cycles just fine...

Have some Norma made 500 Jeffery brass on order and will cut it in half to see how it compares to the other stuff...

Mr. Whidden at Whidden Gunworks is making me the dies for the 338 Wolverine and 375 Mjolnir
it's a waiting game now !

I would like to thank all those who were concerned about the safety issues about running a Rem 700 for these cartridges, the info from you and several other areas of input the decision was made not to use the Rem700 for this project, based on the fact that the knowledge of the forum members here far exceeds mine in so many ways...... I will follow safety protocols........

I am now stuck with a fully tricked out factory 300 Rum originally intended for the project,

Rem Factory bbl in 300 Rem Ultra Mag (only 20 rnds fired)
McMillan M40A1 HTG stock in Forest camo
Jewell Trigger
Nightforce 40 moa base
Nightforce 1" 30mm Ultra Light rings
Sightron SIIISS 6-24x50mm MOAR2 scope
Seekins 3.9" detachable mag system and 2 mags (not installed yet)





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The 375 Mjolnir had some changes made to it also to maximize case capacity and to include the larger diameter rim of the 500 AHR......



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Rocky Mountain,

Have yet to receive my custom case forming dies from Whidden and the reamers from PT&G...

will be using a 30" 10 Twist Benchmark barrel for the 375 Mjolnir
so may not have the full potential of this round, have a long wait for a 34" er

also a 30" tube for the 338 Wolverine until I get the longer one...

the Pigman shoots 250 gr. Hornady bullets at 3400 fps in his 338 Twisted Pig,
my 338 Wolverine has a bit more case capacity and the tougher 500 AHR brass,

without being too optimistic.... my velocity goal for the 338 is around 3200 fps with 300 gr bullets but that is just an estimate based on case capacity and velocity comparison to other cartridges,
 
What a cool project Swamp, you and I have similar tastes. I cant wait to see how these turn out. Thanks for taking us through the process. Best of luck to you
 
Any idea how this compares to .338-378 Wby case capacity/performance and .338-416 Rigby case capacity/performance?

Seems like itll fall right between the .338-378 and .338 Allen Mag?

Also, not trying to go off topic. But has anyone heard any recent updates on Mr Daves .375 Viersco Magnum? Has there been anyone else to wildcat off the .577 T-Rex case? I know State Arms or something like that used to have the .375 Mach V, a .375-50BMG. But has there been any recent .375-416 Barrett wildcats or .375-50BMG AI wildcat developments?

Mr Swamplord, what velocity are you expecting with the 350-400gr Cutting Edge VLD solids? If youre planning on testing with those of course... Either way both of these cartridges with the right boolits should make great 2400-2800yd cartridges easily.
 
Laser......


I posted this info earlier and all the case capacities are from the ammo guide website.... the case capacity for my 338 Wolverine is from the Quick Design software...

I don't know how accurate either source is and will be verifying that info as soon as I have a handful of fired cases in my hand and will post the info on this thread......

338 Wolverine case water capacity 145.2 gr


approx. 18 gr. more than the .338 Excalibur
23 gr. more than the .338-378 WBY
27 gr. more than the 8.59 Lazzeroni Titan
33 gr. more than the .338 Lapua Mag
37 gr. more than the .338 Edge
40 gr. more than the .338 Norma Mag and .338 RUM
62 gr. more then the .338 Winchester Mag
(these are ammoguide water capacity estimates)

all these estimates may vary + or - a grain or two, just a ball park comparison to give you an idea of case capacity.......

the 338 Wolverine is based on the max case length of the 500 Jeffery.....

another option I have been playing around with is using the max case length of the 500 AHR (about 1/4" longer) just use the 338 Wolverine reamer and go deeper, Quick Design shows about 10-12 gr more capacity but will require deep seating of bullets because of COAL limitations .... on a larger action It won't be a problem..... I will probably end up doing that as soon as the bbl needs to be set back, I'll just set the bbl back a few threads and run the reamer in deeper , touch up the muzzle and give her hell !

338 Wolverine + Teeth ? lol....

I do have plans for using the heavier CE bullets, just haven't got my hands on any yet and couldn't tell you the velocity without lying .......
 
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