12.9x63.8mm or 500 Short A-Square or 500 SRE NEW ADDITION

Are these 3 different cartridges, or the same cartridge with 3 different names?

Yes!

Hello All,

After posting about my Buhmiller 416 Brevex Mauser with its Buhmiller Muzzle Brake, one of the forum members "xausa" told me about a 50 cal. rifle that he had custom built back in the early 1970s. On that rifle he also used a Buhmiller Barrel with a Buhmiller Muzzle Brake.

He explained that his 50 cal wildcat cartridge was called the 500 SRE. (Short Range Express) It was based on a shortened 460 Weatherby case opened-up to 50 cal.

I inquired about getting some photos of the rifle because of my interest in its Buhmiller barrel and muzzle brake. Although he had sold the rifle long ago, he indicated that he still knew the purchaser and could get me some photos. In fact, he indicated that the rifle "might" be available for purchase if I was interested. It turned out I "was" interested, and the rifle "was" for sale.

And, the 500 SRE is now residing here in Wisconsin.

The 500 SRE uses a 460 Weatherby Mag case shortened to exactly 2-1/2" and opened up for the 500 Nitro Express bullet (.510 dia) It has a slightly blown-out shoulder, similar to the 500 A-Square, which increased the case capacity. Although shortened, it has the same ballistics as the 500 Nitro Express which was loaded with a 570g bullet at 2150 ft/sec. Nice thing about this cartridge is that with its shortened length it can be used in a more affordable "standard length" bolt action rifle instead of a more costly Magnum Length, or very expensive Double Rifle.

While I was waiting for the rifle to arrive, I searched high and low for reloading dies - and I found none. I contacted both RCBS and C4 and they quoted me $350-$500 and a 6-9 month delivery time. I kept searching. Surprisingly, I found a RCBS 3-die set of 12.9x63.8mm JDJ dies for sale on ebay for $195. I did the math, 12.9mm = .507 inches and 63.8mm = 2.507 inches. That's pretty close. I made a phone call to RCBS and they identified the dies as experimental dies for JD Jones of SSK Industries. They said they were based on a 460 Weatherby case shorted and opened-up to 50 cal. I took a $195 gamble and purchased the dies. Phone calls to SSK Industries confirmed a wildcat cartridge based on a shortened 460 Wby case and opened up to 50 cal.

With the rifle came a set of neck sizing dies for a vintage Belding & Mull tool, and ten fired cases. When the 12.9x63.8mm JDJ dies arrived, I shortened a 460 Wby case and ran it into the FL sizing die. I was pleased to find that it exactly matched the 500 SRE cases. It looks like JD Jones came up with the same idea albeit 20+ years later. And, instead of using 460 Wby cases, I bought some 500 A-Square cases and shortened them so the headstamp would say "50". Interestingly, the A-Square manual shows a 460 Wby case shortened to 2-1/2" - its called the 460 Short A-Square. So, since I used shortened 500 A-Square cases, it stands to reason that this is a 500 Short A-Square. A second contact with SSK resulted in JD Jones saying he'd send me loading data.

I was very pleased with the rifle. The rifle was built by "Harry W. Creighton" (Master Gunsmith, Nashville, Tennessee ) in 1971 on a customized Winchester P-14 Enfield action - It was built especially for xausa. British Inspection stamps and Proof Marks show that this rifle originally went to England, and then came back.

The rifle specs are as follows: 24" Buhmiller Barrel with Buhmiller Muzzle Brake - Sourdough Front Site - Forward Under-Barrel Secondary Recoil Lug - DT Cock on Opening Upgrade - Timney Trigger - Lyman 48 Receiver Sight - weight= 9 lbs 14.7 oz - 13-3/4" L.O.P.

And much to my delight, it fits me like a glove. Its so very nice to have a rifle where all its History is known. I'm also hoping the Buhmiller Muzzle Brake works as well on this rifle as it does on my 416 Buhmiller Brevex.





















This weekend was the first time our Wisconsin temperatures were above freezing in about a month and I made a quick trip to the range. I tested the 500 SRE with some beginning loads with both 570g Hornady and some 350g lead gc bullets.

I always start conservative. The 570g velocities averaged 1665 ft/sec with a calculated recoil of 48 ft/lbs. The 350g velocities averaged 2285 ft/sec with 41.6 ft/lbs calculated recoil. Both loads were at a "fun" level with the 570g load showing more felt recoil than the 6 ft/lbs increase would indicate. It may be that the Buhmiller muzzle brake functioned better at the higher velocity level.

I later increased my 570g load by a grain to obtain 1695 fps average velocity with 49.8 ft/lbs recoil level with no noticeable increase in felt recoil.

This is my only Big Game rifle with an aperture rear site and I found it easy to use with fast target acquisition and "fine" aiming ability. Accuracy was absolutely amazing with both loads. I'm looking forward to working my way up to 500 NE velocity levels to see if the Buhmiller muzzle brake tames the recoil as much as it does with my 416 Rigby Buhmiller.





Shortly after shooting the targets above, I received the promised loading data from JD Jones. He listed bullet weights of 400g - 450g - 485g - 500g - 525g - 600g with IMR 3031, IMR 4198, and RX-7 powders. There were 28 different loads, all chronographed with corresponding group size listed from a small of "one-hole" up to 3 inches. Several were listed as 1/2". Not sure what the difference is between a 1/2" group and a one-hole group?

Updates to follow.

I wish you the very best with your new and very
interesting rifle. May you cleanly kill all the game
that you seek with it. Obviously you'll have no trouble
getting cartridge components.

Nice report !

very nice!

What is the water capacity of a fired case?

1/2" group means a gross size on about 1 inch..

Photos that XUSA emailed to me a few years ago. Nice rifle!

Load data for 510 A Square Short in "Any Shot You Want". I have it if you cannot find the book or data.

Kenya in 1972. Puts Stewart Granger to shame!



In his gun room

Hello WoodHunter,

Yes, I have those pictures also. That is xausa's 505 SRE rifle. It is identical to mine except it has a .505 dia bore instead of .510 dia. It also has a Buhmiller barrel but no muzzle brake.

I have the A-Square book, but find no data for the 510 A-Square Short.

quote:

Originally posted by buckstix:
Hello WoodHunter,

Yes, I have those pictures also. That is xausa's 505 SRE rifle. It is identical to mine except it has a .505 dia bore instead of .510 dia. It also has a Buhmiller barrel but no muzzle brake.

I have the A-Square book, but find no data for the 510 A-Square Short.

So there are two rifles? One at .505 and one at .510? Interesting. I thought the stock figure and finish looked different, I blamed it on a refinish job.

My old age may be confusing the 460 short with the 510 short, have not peeked at Art's book in several years.

What does a guy lose first at the onset of old age? Sorry, I cannot remember the answer to this question.

Yes,

I think you did confuse the 460 Short A-Square with the 500 Short A-Square. Only the 460 is in the book.

and ........

Memory is the "second" thing that goes .... I forget what the first is?

Take off the belt and the short .510 would be a sister of the 500AccRel.
The 500AccRel has a 2.65" case length, with the same "Rigby-esque" case head.

Hello 416 Tanzan,

Thank you for the reply. I already have the 28 different loads from JD Jones and another dozen or so that I worked-up myself and some original loading data from xausa.

Right now I'm more concerned about finding bullets at a good price - got any suggestions?

For hunting, I've decided that the GSC 450gr HV and the 350gn+tip CEB LeverRaptor are the best bullets, good for buffalo, good for plains game.

But both are expensive. But what is $2 or $3 dollars when tracking a large beast? I've shot 450gn Woodleighs for practice, but ultimately, the GSC needs its own load data.

quote:

buckstix: Right now I'm more concerned about finding bullets at a good price - got any suggestions?

Single loaded 50 BMG milsurps.

I'm interested in hunting bullets.

Have you checked into Hawk bullets? I used to shoot lots of Barnes originals in my 500 A-Square but I don't know if they are still available. The 450 gr fn Original 50-110,50 Sharps bullet may still be available.

hornady DGX do just fine -- for "good price" .. they aren't the best you can get - which is good for practice bullets -- cost beats many others... accuracy is there ...

I think Forrest thought you were looking for plinking bullets, as he and I both shoot the BMG pulled bulletss for that purpose

Hello Cold Trigger Finger,

Hello jeffeosso,

thanks for the reply. I shoot a lot of Hawk bullets, but they run over $1 each. Hornadys are about $1.20 each. I was hoping to find something a little more reasonable.

I never thought to try 50 cal military pulls - what do they cost?

I've got some .512 CP bullets on the way - 435g and 525g - to try. They are a gas-checked lead bullet. One of my groups shown above was with their 350g bullets. I also used them in my 505 gibbs with good results.

I have tried some plain base cast bullets - with VERY BAD results.