Ron,
Oops... I'll correct and repost as soon as I can get back to my laptop...

Neck dimensions/clearance in the chamber - you'll have to decide whether you'll primarily be using the Lapua mfg/brand 338 Lapua Mag brass or Hornady' Rigby brass as the Hornady brass is much thinner in the neck. Even the Hornady mfg/brand 338 Lapua Mag brass is thinner in the neck than Lapua mfg/brand brass. Maybe Jamison will come back on line one of these days as their mfg/brand 338 Lapua Mag brass was pretty close the Lapua's in the neck and wall thickness... Maybe go with a 0.003" clearance which would help with slop when using non-Lapua brass though, as you note, you may have to thin and uniform the necks of Lapua brass. Guess it depends upon how quickly you want proper headstamped brass...or just add 510/338 Lapua Magnum on the opposite side of the barrel and you're covered...

Tan,
Ron's 500 Mbogo Short/50-12 is truly a fireform (just like he did in the 12.7x68/49-10), clean and uniform the brass length, and load and go scenario... Ought to be great with a 3.5" magazine...keeping a spitzer nose protrusion at 0.770" max or just go with a 3.6" magazine length and be done with it...

Rob,
I know Michael discussed the brass abrading issue with Dan (CEB CEO) but, at least in his case, he fired the same batch of bullets in to other 475 B&M rifles with same manufacture/same twist rate/same chamber specifications and two of the three gave perfect grooved bands while one single rifle gave abraded bands with each firing. That rifle has gone back the the shop for a replacement barrel from PacNor; PacNor is going to bore scan the barrel to determine what went wrong in the mfg process.

Also with Tan's recent firing of 570gr TSX bullets in his 500 AccRel with poor accuracy - Tan and Ulrick (Buffalo) desire accurate 200-300yd rifles - I think the issue has moved as much to the shorter freebore to enhance accuracy pure hunting bullets (neither desire to use milsurp bullets) than to resolve the band abrading issue with the original 500 AccRel 1.250" freebore specification.

I understand that Ulrik and Hatting still intend to expend one is his two new barrels in a test by progressively increasing freebore from a 1/2 caliber through 1.25" freebore to identify where the accuracy drops below long range acceptability and where the band abrading occurs - if it occurs - but at least this should put the freebore questions to rest.

Personally, I believe Ulrik's original barrel may be at fault based upon Michael's results with a far shorter freebore with one of three identically prepped 475 B&M rifles; his and Hatting's testing will prove or disprove this belief. I also believe the 1.25" freebore chamber in the 500 AccRel (.510 caliber) will not deliver the 300yd accuracy that RIP has demonstrated with the 0.252" freebore in the 12.7x68/49-10 (.500 caliber) at 300 yds. Of course someone could easily disprove this as well by firing some 300yd groupings with the 450gr .510 GSC HV bullets from a 500 AccRel for comparison with RIP's 300 groupings with the 430gr .500 CEB MTH bullets from the 12.7x68/49-10...

quote:

Of course someone could easilprides prove this as well by firing some 300yd groupings with the 450gr .510 GSC HV bullets from a 500 AccRel for comparison with RIP's 300 groupings with the 430gr .500 CEB MTH bullets from the 12.7x68/49-10...

Unfortunately, I couldn't get ahold of any GSC lightweight (450 grain) bullets this summer, so I could'ny run the accuracy test that I had hoped. Meanwhile, I'll probably have a new barrel before I get my hands on this so someone like Jeffeoso will need to run the GSC tests. Maybe the 475 gr CEB could be tested for accuracy in a long throat, too. Tests of 100 yards are OK, since a .5-.75" group at 100 is going to be pretty good at 300, too.

quote:

Originally posted by 416Tanzan:

quote:

Of course someone could easilprides prove this as well by firing some 300yd groupings with the 450gr .510 GSC HV bullets from a 500 AccRel for comparison with RIP's 300 groupings with the 430gr .500 CEB MTH bullets from the 12.7x68/49-10...

Unfortunately, I couldn't get ahold of any GSC lightweight (450 grain) bullets this summer, so I could'ny run the accuracy test that I had hoped. Meanwhile, I'll probably have a new barrel before I get my hands on this so someone like Jeffeoso will need to run the GSC tests. Maybe the 475 gr CEB could be tested for accuracy in a long throat, too. Tests of 100 yards are OK, since a .5-.75" group at 100 is going to be pretty good at 300, too.

This is true, I'd like to be piggish and ask for for 50yds, 100yds, and 300yds but that likely won't happen...

Reason for the 3 distances is that is what RIP has already posted. Plus - I think it was on Mediums, or was it smalls - anyway this weekend was reading a post where with 50yd, 100yd, and 200yd groupings with the group tightening up as the distance got longer. RIP's groupings stayed pretty close throughout his target posted range. It would be nice to verify whether the 1.25" freebore 500 AccRel maintained its 50yd groupings at 100yds and 300yds... After all, there's zero reason that the 500 AccRel shouldn't deliver comparable accuracy to the 12.7x68/49-10 as the cases are virtual twins with only a 0.010" difference in bullet diameter...

Perhaps Gerard could make sure that a sufficient number of the 450gr .510 GSC HV bullets were delivered to their USA office fairly quickly to answer the question. Not sure if any of the 500 AccRel owners from down under have access to the GSC HV bullets to conduct the testing but that also could be an alternative...

for 300 yard testing you'll need to make sure that the talons are working as planned, no loose flyers, etc.
So a tight 100 yard group without talons and a tight 100 yard group with talons should start the parade.

quote:

Originally posted by 416Tanzan:
for 300 yard testing you'll need to make sure that the talons are working as planned, no loose flyers, etc.
So a tight 100 yard group without talons and a tight 100 yard group with talons should start the parade.

If you’re planning on testing with the 475gr .510 CEB BBW#13 HP NonCons with Talon Tips they’ll have to be singly feed as they COAL will be too long to feed from a M77 magazine, likely would require a CZ 550 Magnum action or Montana PH action to magazine feed the rounds. Who knows when ESP Raptors will be available in .510 caliber…

I've been checking out GSC and there may be a very good use for any old 1.25" freebore barrels.

It seems that GSC sets their driving bands at .512" diameter. While those will undoubtedly work in a .510" barrel, it might be better to reduce that to .511" if a barrel is using .511" freebore, even if short-throated.

So what does one do with a .512" bullet?

Carefully drop/slide it into the breech of a 1.25" long, .511" freebore barrel. Gently push for 0.8" or until nose ogive reaches the beginning of leade/riflings, perhaps marked by a flat-ended cleaning rod already in place.

Remove from breechend using long, flatend cleaning rod or equivalent.

The result should be a nicely swaged .511" bullet, perfect for use in a 500 AccRel of whatever throat length. I would think that this would improve accuracy in longthroat versions of 500 AccR. Also, a .511" bullet would probably seat better in a case neck than a .512" bullet.

And for those with an old barrel with long .511" freebore, that barrel can become a simple bullet swager.

(The above has not been tried yet, since I did not have GSC bullets this past summer. But I look forward to testing this Fall/Winter)

quote:

Originally posted by 416Tanzan:
And for those with an old barrel with long .511" freebore, that barrel can become a simple bullet swager.

F... Tanzan - you have too much time...

Jim,
I have a bunch of 535-grainers I need to shoot.
Anything in the 450 to 570-grain range will be good,
and I note your suggestion elsewhere of the 500-grain FN solid for the 500 Mbogo Short aka 50-12:

416Tanzan,

You want .510" diameter bullets for a .510"-grooved barrel with a .511" diameter free-bore.

I got a custom, 30-dollar, push-through bullet sizer from Lee made to .510" sizer spec.
prof242 tipped me on these, as well as the use of some STP oil-treatment to use as lube.
That worked well on the .512"-diameter GSC bullets.

You really must explicitly state .510" when ordering the bullets from GSC.

GSC purposely makes .512" for .512"-grooved barrels (claimed CIP 500 Jeffery and 500 NE).
They make .510" diameter also, like the 570-grain FN, and the big 50BMG target bullets.

.512" diameter GSC bullets might revitalize the 50/70 Govt.

BUT: 570-grain GSC FN discontinued?
As buffalo says?
Just to spite me?

North Fork and CEB will keep me supplied in both .500 and .510-caliber bullets.

Yep Ron - I was told so... but they'll make what you want... So I ordered some 570 grs FN's.... And they arrived today...

Thanks Ron, for the heads up.

My next order to Midway will have the Lee .510" swager for $19.

Ok – back to page one with an Update…
The Manson’ 500 AccRel Nyati finish chamber reamer was paid for today and is shipping today to McGowen – Dan Wynne should have the reamer in hand early next week!

Many kudo’s to Dave Manson Precision Reamers for a job well done! And many thanks to Dan Wynne for their assistance in this endeavor!

Great news.

thanks Jim -- thanks for keepng the faith, guys

Hey Jeff,
Thank you for allowing this reamer to be housed with your reamer and gauges; most definitely appreciated your courtesy.

Jim,
thank you guys for having the faith to try -- lets see what changes and if they are for the better.. if so, I'll have mine modified and we'll get "all right"

quote:

Originally posted by jeffeosso:
Jim,
thank you guys for having the faith to try -- lets see what changes and if they are for the better.. if so, I'll have mine modified and we'll get "all right"

The reamer for a 0.25" freebore is now at McGowen's.

It is called 500 Accurate Reloading Nyati, in order to keep the freebores separated: the 1.25" parallel-freebore version separate from the 0.25" parallel-freebore version.

The nyati (buffalo, Swahili), of course, are ready to challenge whether or not we've gotten this right.

In my personal opinion, the .500" AccRel Nyati is the best designed case/chamber I've seen in very, very long time.

Lapua .338" brass (cheap military once fired)

20 degree shoulder

.510" long neck

.250" freebore

What else is there that is so good?

Pyzda

quote:

Originally posted by Pyzda:
In my personal opinion, the .500" AccRel Nyati is the best designed case/chamber I've seen in very, very long time.

Lapua .338" brass (cheap military once fired)

20 degree shoulder

.510" long neck

.250" freebore

What else is there that is so good?

Pyzda

Well, Jeff Smith will thank you for the compliments, and they do fit, but you may be describing RIP's slightly longer version on the Lapua brass.

The 500 Acc Rel and the 500 Acc Rel Nyati only use a 2.65" case,
a Lapua-size head that has been trimmed 0.07" in case length in order to fit into a 'standard' length action at a maximal stretch of a magazine.

Parallel freebore is 0.255"

However, the neck on the Nyati is technically 0.456", 90% of calibre, (the reamer is .466", as written up by Capoward and Dave Manson, following on Jeff Smith's original design). This pushes the overall length about as far as possible with a goal of still fitting in a standard 'WinMag/Ruger' length action and magazine.

The shoulder is listed as 21° as calculated on AmmoGuide, though the reamer specs call for 20°. I guess we will have to see what the final outcome is, though I wouldn't know how to measure fired brass to such accuracy on the rather small shoulder.

In sum, yes, it is a remarkably balanced cartridge for taking the largest game on the planet. It is a giant step forward from the "ultimate African bolt cartridge" that Winchester produced in 1956 for African game. The 500 Acc Rel Nyati has an 11% calibre increase in diameter and a 2000 ftlb. increase in energy over the 458 WinMag. Booya.

Buffalo should be testing something over in Denmark in the "Hatten version", and we hope to do some testing in the US as soon as the rifle is returned from McGowen barrels.

RIP, too, is working on his 2.7" case in his 50-12 variant with perhaps closer to the perfect design that you mention.

The difference is that the Nyati should still fit in standard actions while the 50-12 is designed for H&H length actions/magazines.

In either case, pun intended, the cartridge is close to an optimal balance for an all-around African stopper in a rifle that can be reasonably maneuvered and handled by a practiced rifleman.

(Hmm, should that be 'rifleperson', or are the hunting ladies good with the term rifleman? Either should work, and honor is due to whoever would take such a cartridge to the bush. A lady did test fire my 500 AccRel [it has no muzzlebreak] from a bench last summer with a comment that it was stiffer recoil than anything she had shot but that it seemed manageable and reasonable for the intended quarry. Everyone who shot it that day considered it fun and controlable, though perhaps on the maximum edge. Paper, sand bags, and milk jugs took a beating that day.)

Tanzan

thanks for your correction on some of the details, however even with these minor variations, the case/chamber is nearly perfect.

20/21 degrees is nothing, I would even accepted 25 degrees and still be happy.

The shorter .456" neck is still 0.9 cal., not as good but no complaints from me.

Any cartridge where you can use Lapua brass is one step ahead over any other brass.(RWS may be still better).

Military once fired .338 Lapua cases for a fraction of the cost of new cases is a bonus.

Pyzda

thank you, I do believe.. and the final polish appears to be a group effort -- i am very much complemented by those committed to the design, and very close flattery as well--

you can make the brass from lapua -- i prefer the hornady brass, actually .. it just forms better..

The new throat on the "500 AccRel Nyati" which mimics the throat of my 12.7x68/49-10 (.500/.338 Lapua Magnum) should be a very good improvement.
I am happy to have provided the guidance,
so happy that I am using the same throat on the "500 Bateleur" formerly known as "500 Mbogo Short," and still known by the aka of "50-12."
That is indeed a .510/.338 Lapua Magnum, with 2.700" max case length,
which I was thinking of doing long before the 500 AccRel was just a glimmer in jeffeosso's eye,
or the 500 Mbogo 3-Inch in mine.

Only 0.050" case length difference is not much difference between the 500 AR Nyati and the 500 Bateleur.
The 500 Bateleur will fit a standard M98 Mauser or Ruger Hawkeye, if the 500 AR Nyati will.

I prefer the better feeding mechanics allowed by a 3.5" or longer box, for the 500 Bateleur.

Personally I prefer Lapua brass over any other, I like to LOAD and that means to the absolute safe maximum.

So far only the Lapua brass lives to my expectations.

What I want from the brass is to last with maximum loads and not to expand primer pockets after 2-3 reloads.

Where forming is concern, there is nothing that good and frequent neck annealing can't fix.

Nice job gentleman, I may even consider one of these as a 20" barrel throw around rifle, just to have something powerful enough and handy every day gun.

Pyzda

quote:

Originally posted by RIP:
The new throat on the "500 AccRel Nyati" which mimics the throat of my 12.7x68/49-10 (.500/.338 Lapua Magnum) should be a very good improvement.
I am happy to have provided the guidance,
so happy that I am using the same throat on the "500 Bateleur" formerly known as "500 Mbogo Short," and still known by the aka of "50-12."
That is indeed a .510/.338 Lapua Magnum, with 2.700" max case length,
which I was thinking of doing long before the 500 AccRel was just a glimmer in jeffeosso's eye,
or the 500 Mbogo 3-Inch in mine.

Only 0.050" case length difference is not much difference between the 500 AR Nyati and the 500 Bateleur.
The 500 Bateleur will fit a standard M98 Mauser or Ruger Hawkeye, if the 500 AR Nyati will.

I prefer the better feeding mechanics allowed by a 3.5" or longer box, for the 500 Bateleur.

w0w..

quote:

Originally posted by jeffeosso:

quote:

Originally posted by RIP:
The new throat on the "500 AccRel Nyati" which mimics the throat of my 12.7x68/49-10 (.500/.338 Lapua Magnum) should be a very good improvement.
I am happy to have provided the guidance,
so happy that I am using the same throat on the "500 Bateleur" formerly known as "500 Mbogo Short," and still known by the aka of "50-12."
That is indeed a .510/.338 Lapua Magnum, with 2.700" max case length,
which I was thinking of doing long before the 500 AccRel was just a glimmer in jeffeosso's eye,
or the 500 Mbogo 3-Inch in mine.

Only 0.050" case length difference is not much difference between the 500 AR Nyati and the 500 Bateleur.
The 500 Bateleur will fit a standard M98 Mauser or Ruger Hawkeye, if the 500 AR Nyati will.

I prefer the better feeding mechanics allowed by a 3.5" or longer box, for the 500 Bateleur.

w0w..

+1

I thought these excerpted posts might be of interest…

quote:

Originally posed by RIP: Posted 27 October 2012 02:26
Excerpts…
Jamison/Captech International .338 Lapua Magnum blank basic, cylindrical brass starts off at +2.750", average length about 2.753" on a quick re-check.

This is sized in 12.7x68/49-10 die for case body and shoulder.
Then it is trimmed to 2.700".
Then it is necked up and neck sized in 500 Jeffery and 500 Mbogo dies, staying off the shoulder and not belling the case mouth.
Then it is final trimmed to 2.690", minimum length.

I did this to just 3 cases.
Average gross water/case capacity: 132.4 grains

Excerpted from:
http://forums.accuratereloadin...4711043/m/1681060181

quote:

Originally posted by buffalo: Posted 30 January 2012 10:48
I fire formed some brass a few days ago - my 500 Acc Rel rifle almost completed...

Case cap in fireformed brass:
338 Lapua brass (from Lapua): 136 grs water
416 Rigby - Norma brass: 135 grs water
500 Acc Rel brass- once fired (Quality Cartr): 137 grs water
416 Rigby - Hornady brass : 141 grs water

Extracted from: http://forums.accuratereloadin...043/m/5931027531/p/6

quote:

Originally posed by capoward: Posted 23 May 2012 03:52
Excerpts…
Multiple-edited post-excerpts by RIP:
A la Doc M's MIB extractor head spacing research. Using the extractor of a Winchester M70 and the rimless-rim of the case for headspace on fireforming; Just touch off a standard .338LM in a 49-10 chamber… Mine were fire formed with a hot loaded 200-grain Nosler ballistic tip .338/200-grain bullet.

Lapua-brand .338 Lapua Magnum Commercial Brass:
New Unfired Case Length: 2.717"
Fire Formed Case Length: 2.707"
Fire Formed Case Trim Length: 2.647".
Fire Formed Case Capacity: 131.45grs water

Case capacity:
Trimmed Case Length: Fire Forming Commercial: 131.45grs water
Trimmed Case Length: Fire Forming Commercial & Full-Length Resized: 129.9grs water after second full power load and second resizing
Untrimmed Case Length: Hydraulic Forming Die & FLR Unfired Commercial: 123.458grs water
Untrimmed Case Length: Hydraulic Forming Die & FLR Once Fired Military: 108.026grs water

Extracted from:
http://forums.accuratereloadin...043/m/5931027531/p/6

Thanks to RIP for providing the bulk of this information.

My pleasure, and thank you, Jim, for compiling all that information.

The .500 AccRel Nyati finish chamber reamer was delivered to McGowen in early and Tanz has his re-barrel underway, though not finished, I thought it would be good to bring this thread back to page 1 as well as update it with RIP has posted on other threads that are of value to .500 AccRel users… So here goes ---

I pulled this information from the Good News; Jamison Rides again. thread:
http://forums.accuratereloadin...043/m/3101017971/p/1

quote:

Originally posted by RIP:
Looking good:

http://www.captechintl.com/products.html





Interesting items on their web site logo page:
.408 Chey-Tac and .375 Chey-Tac brass, and says loaded ammo too!

"All calibers are offered as empty cartridge cases and as loaded ammunition.
For more information call us at 1 (605) 791-1974"

The brass as last made by Marc Jamison was best quality stuff.
Hopefully Captech brings all the fine tuning worked out by Marc Jamison to the current operation.

quote:

Originally posted by RIP:
Hi Dave,

Good to hear from you. Glad you are still kicking. Me too.

How many projects do I have on the go, you ask?
Heh, heh, too many, since I never get finished with one before I start another ...

The latest four I am still working on are (forget for now the many more from the past I need to complete load testing):

1. .375/404 Jeffery Saeed of 2012: Loading some ammo for this now, finally got the reloading dies a few days ago from Hornady.

2. 400 Whelen (a "me too" with Rusty McGee doing the workups in his M98 rifle, and building one for me on a Ruger Hawkeye ... one of these days)

3. 12.7x68/49-10: .500-caliber on the .338 Lapua Magnum case. Needs to finish some load development.

4. 500 Mbogo Short/50-12: .510-caliber that is the latest startup, pictured here, formed from Jamison brass,
trimmed from 2.750" blank basic 338 Lapua to 2.700" maximum:




Did I mention that the Jamison finished .338 Lapua Magnum brass is even more uniform than Lapua brand,
in linear and weight dimensions,
and intermediate in weight between Hornady and Lapua brands?

From the 500 Mbogo Short thread:

Chris Freeman, production manager at Captech International:

Says the Jamison International blank basic brass will be offered again in 2013, whenever they make another run of it.

Sounds like they will offer any blank basic that they routinely make, whenever they make a new batch of it,
and wildcatters can buy it, routinely,
if they get you on the wish list with office manager, Kathy Greenshaw.
Contact info above.

The blank basic is made as a preliminary step for each of the finished brass they make, of course,
and that includes .416 Rigby blank basic that is +2.945" for use in the 470 Mbogo. They do have the bunter for "Mbogo 470" headstamp."

I am on the wish list for blank basic 30-06 and 338 LM.

quote:

Originally posted by RIP:
Jamison makes 600 Overkill.
I wonder if they would supply "basic blank" 30-06 brass that is +2.5" to use in forming 400 Whelen and such?
I have inquired.

Here is the .338 Lapua Magnum fully formed and the "basic blank" that seems to have a diameter out near where the shoulder will be formed,
that is identical to that of the 500 Mbogo Short/50-12 and the 12.7X68/49-10.

Initial measuring and weighing shows that Jamison is even more uniform than the best of best Lapua brand, though it is lighter than Lapua,
it is just 0.9 grains heavier than the excellent Hornady.

I will not bore with anymore actual measurements, until specifics about a certain wildcat come up on another thread,
except to add that the "blank basic" .338 Lapua brass is exactly 2.750" on average, +/- 0.001" in length,
and weighs 325.6 grains on average, which is 14.2 grains heavier than when it is fully formed, trimmed, and headstamped to .338LM.

And I pulled this information from the 500 Bateleur: RIP 500 MS thread:
http://forums.accuratereloadin...4711043/m/1681060181

quote:

Originally posted by RIP:
Jim,
Got the brass, thanks.
7 pieces of "Lapua 98" headstamp, and one civilian case that has the pretty annealing.
It will be interesting to but it through the paces Missouri style, "show me."
Whomever shot that brass had it loaded hot in a rifle with a plunger-style ejector:

quote:

Originally posted by RIP:

quote:

Originally posted by buffalo:
I just bought 200 pcs of oncefired military Lapua brass in 338 Lapua.. Around 1$ a piece ... Not bad eh??? Would be good for some extra 500 AccRel brass....

Grab it when you find it.

So far little difference between the milsurp and the civilian stuff.

Average weight of 7 pieces of the milsurp is 341.6 grains, high 342.4 gr, low 340.4.

The one piece of new, unfired, civilian brass that Jim sent weighed 330.9 grains.
One piece of my once-fired .338 LM civilian brass pulled at random weighed 330.6 grains.

All the above weights were after de-capping and FL sizing.
The cratered primers made it tough to measure length, so I decapped them.
Milsurp average length was 2.726", high 2.728", low 2.724".
Max allowed brass length, for .338 LM, IIRC, is 2.724", so trim-to is 2.714".
Jim's new civilian .338LM case was 2.719".
My once-fired .338LM case was 2.724".
No water capacities until after they are fired to 12.7x68/49-10, and trimmed to a uniform 2.650" for this exercise.
Max 2.657" and trim-to is 2.647" for the 12.7x68/49-10.

I cut a milsurp case (MIL) and a civilian case (CIV) with a roto-tool cutoff wheel.
I see no significant difference.
So far only about 11 grains heavier for the MIL case.
That could be from brass alloy used, or lot-to-lot variation between batches?
Anecdotally: The MIL brass may be harder than the CIV brass.
The MIL brass was a little harder to cut ... maybe? Maybe not?
So far, so good.









Hardness of neck and shoulder area might be a requirement for military use. Use once and discard.
The milsurp does not seem to have the signs of annealing after final forming.
Civilian brass is meant to be reloaded.
Lapua does a beautiful annealing on the civilian brass, after the final neck-down from basic cylindrical.
New civilian brass blows out very nicely in fireforming.
If I split any of the milsurp brass necks on fireforming, I will stop and anneal what's left of the sample.
This is a test.
Might be that the milsurp brass just needs to be annealed for best results in fire-forming into 12.7x68/49-10, 500 Bateleur/50-12, 500 AccRel Nyati, etc.

quote:

Originally posted by RIP:
Jim,
That is just some off-centeredness of the thick cutoff wheel.
You try to cut asymmetrically so that the face of the wheel goes down the centerline, and you end up with a "skinny half" and a "full half" of sectioned case,
because of the thickness of the cutoff wheel, crude tool.
It aint' perfect.
Primer holes are actually same.
Heck, the milsurp and civilian are same throughout, except for annealing or brass composition, by my guess.

I pulled this information from the "Another 500" Now At Ammoguide: 12.7X68 49-10 thread:
http://forums.accuratereloadin...043/m/3321020671/p/1

quote:

Originally posted by RIP:
Pyzda,
You are right about that.
My annealing with a propane torch and a pan of water is not as pretty as Lapua's but it is not worth risking a case.
Less likely to crack later, even if they survive the initial fireforming.
Might as well get used to annealing the milsurp cases.

Jim,
I see you want me to continue reporting on the test of your milsurp brass on this page.
So be it.
The 500 Bateleur/50-12 has not hatched yet.
The 12.7x68/49-10 "bird of prey" soars already.

That "Lapua 98" brass has a bright and shiny appearance to it that needs some dulling and softening in the neck and shoulder area,
before it gets blown out from .338 to .500 caliber.
Wildcatter rule of annealing:
Anneal before necking up and after necking down,
unless it is new brass that has come from the Lapua factory freshly annealed after being necked down from cylindrical.

Now all three threads have been appropriately updated!

It appears that RIP is getting all of the service at McGowen. At least I'm encouraged by the following update, repasted from the Bateleur thread.

quote:

from RIP
Two McGowen barrels in hand now.
Both are .510/.500 rifling, 1:12" twist, stainless, and about 28-1/8" long, nominal 28" contoured blanks with 1.2" shanks.

1. McGowen Medium Target contour (a straight taper):
Weighs 5 lbs. and 6 ounces, and has muzzle diameter of 0.875", breech/shank diameter 1.203", sanded-shiney finish, as expected. tu2

2. McGowen's copy of No.6 Pac-Nor Sporter contour:
Weighs 3 lbs. and 11 ounces, muzzle diameter 0.750", breech/shank diameter 1.202", with beveled edge on breech face, and bead-blasted finish, for whatever reason, nice touch. tu2

Breeches:



Muzzles:



Lessee now, if the lighter sporter barrel is cut and crowned at 23", the muzzle diameter will be 0.800",
and that barrel will be nearly two pounds lighter than the target contour barrel if it is left 26" long with muzzle diameter of about 0.905".
Cool

Nice barrels, RIP, and we look forward to the follow up reports in the future.

As follow-up daydreaming,

do you think that 500AccRel Nyati ammo will be shootable in the Bateleur? The Bateleur was 0.050" longer if I remember, but will the headspace work? Certainly the opposite won't work, since the case mouth would get scrunched in the Nyati chamber. plus, the Nyati is designed for standard magazines.

quote:

Originally posted by 416Tanzan:
... do you think that 500AccRel Nyati ammo will be shootable in the Bateleur? The Bateleur was 0.050" longer if I remember, but will the headspace work? Certainly the opposite won't work, since the case mouth would get scrunched in the Nyati chamber. plus, the Nyati is designed for standard magazines.

416 Tanzan,
Neither one will fire in the other, unless there is some unpleasant and undesirable crush fit and hard chambering possible,
possibly dangerous, definitely not functional.

The 500 AccRel Nyati has a shoulder diameter of 0.577" at 2.140" from head face/base.

The 500 Bateleur has a shoulder diameter of .571" at 2.161" from head face/base.

The 500 Bateleur has greater case taper and the 500 AccRel Nyati wil not chamber in the 500 Bateleur.

Also, as you state, the 0.050" greater length of the 500 Bateleur (2.700" max brass) will not fit into the chamber of the 500 AccRel Nyati (2.650" max brass).

Also the headspace distance of the 500 Bateleur is 0.021" greater than that of the 500 AccRel Nyati.
The 500 Bateleur has more than one reason why it will not fit into the 500 AccRel Nyati chamber.

But the 500 Bateleur can easily be loaded into the 3.42" box length of the standard action Ruger Hawkeye.

500 Bateleur reference dummies:



I plan to have an FN Mauser M98 with custom bottom metal by Duane Wiebe, fitted by Rusty McGee, that has 3.501" inside box length, drop box, light barrel.
That one-piece bottom metal is built like a bank vault with thick front wall, designed for the 500 Jeffery,
and even better for the 500 Bateleur, no modification needed.

I would also like to have a Weatherby Mark V with 3.8" drop box and heavy barrel.

Either rifle could be single-shot-loaded with the 4.000" COL cartridge, or feed the shorter cartridges directly from the box.

I am still waiting for delivery of the 500 Bateleur reamer:


McGowen certainly does know how to make a .510-grooved/.500-bored barrel.
I have had perfect results with 3 of their 1:10" twist barrels in .510-caliber.
Just thought I might like to try the 1:12" this time.



Did I mention that McGowen knows how to make an excellent .510-grooved/.500-bored barrel?
6-groove twists: 10", 12", 20", 24"
8-grooved twists: 15", 24"

Riflecrank Internationale Permanente

Well, I suppose it's time for a monthly update while we wait for some real action and real data on the 500 Acc Rel.

Here is from the sister 'Bateleur' thread:

quote:

Originally posted by jeffeosso:

quote:

Originally posted by RIP:
Is jeffeosso asking to borrow the 500 AR-Nyati reamer on the 500 Bateleur thread?

Riflecrank Internationale Permanente

Yep. Was feeling lazy. Happy Christmas

The 500AccR Nyati reamer is at McGowen Barrels. So far no barrel has come out with that specific reamer. The Bateleur folk seem to have gotten two barrels in the mean time. It looks like we won't know what this means until next year.

quote:

can i borrow the new AR reamer?

I’ll post here and on the 500 AR thread…

Jeff,
You are certainly welcome to borrow the 500 AR Nyati finish chamber reamer.

I only ask that McGowen complete their pending 500 AR Nyati barrel work for Tanz’ [and for ptaylor (he’s the 3rd partner in this reamer) if he also has a rebarrel job pending] 1st then they’re good to go with loaning you the reamer…

Thanks -- I am planning on cutting a new barrel and testing my proved loads to see if there are gross pressure differences -- I don't think the low and middle loads will matter, but the toppers may --

I look forward to your testing results...

quote:

Originally posted by jeffeosso:
Thanks -- I am planning on cutting a new barrel and testing my proved loads to see if there are gross pressure differences -- I don't think the low and middle loads will matter, but the toppers may --

I actually don't expect too much problem because the loads were pretty tame to begin with.

In the .500" cartridge of RIP he ran energy levels up to 7100 ftlb and 7200 ftlbs, and all with a short throat.

PS: yes, I'm pretty sure that all three of us that went in on the reamer are happy for others to have barrels made with the reamer. If you need it in Texas, you would need to return it to McGowen so others will know how to get a 500 AccRel.

Again, the 500 AccRel is a remarkably balanced cartridge. Plenty of horsepower, small footprint. (Well, smaller than the Jeffrey and Gibbs, anyway.)

Seen on a different thread (TREX brass):

quote:

Buffalo wrote
...
I must admit that I am a lot more tempted to carry my 500 AccRel at 8 Ibs any day.. I just loaded the .510" new design 600 grs North Fork FPS to 2345 fps average and that combo WORKS.

Congratulations. It's shooting.
It's what we've been waiting for over half a year.

We look forward to some pictures and an update on all the details, accuracy, loads, etc.

I need to stop messing around and get my 500AccRel put together...

Got all the stuff to do it, just been lazy.

Pulled from the 500 Bateleur thread...

quote:

Originally posted by RIP:
The .255" length of is more than adequate for milsurp loads.
The Barnes 647-grain XFB has an ogive like milsurp ball ammo.
Seat it and crimp it on the cannelure and you have a COL of 4.000" in the 500 Bateleur.
This is a nice single-shot loader.
Even longer COL and heavier bullet can be obtained with the Hornady 750-grain A-Max, or a 705-grain AAA Harlow target bullet.
But 647 grains is plenty heavy enough for larger varmints.

A sabot load with 150-grain .308-caliber bullet deserves to be checked for velocity and accuracy. It feeds from the box of the Wby Mk V.

This could make for a versatile varmint rifle, with both heavy and light hollow point bullets.
500 Bateleur

That ought to settle the free-bore issue with the 500 AR as well... on the 500 AR Nyati and its 0.255" parallel-sided free-bore.

Jim,
How about this one, the 750-grain A-Max from Hornady,
with COL of 4.475" it will chamber in the 500 Bateleur, with its throat so like the 500 AR Nyati:



Note also how perfectly it fits the neck, full bearing throughout neck, for excellent neck tension,
only the boat tail intrudes into the powder space.

I'd say that is about as long and heavy a beak as this bird needs, for successful 1000-yard plinking.

Oh, tisk tisk, ron.
In your own words " is rip discussing the Bateleur in the 500 accrel thread?" This is called teasing and reminding one of their response in another thread