Unintentional Case Forming Experience
Model 1924 Mannlicher-Schoenauer Carbines were made in 7x57 Mauser for the US market and 7X64 Brenneke for the European market where it was illegal to own rifles in military calibers. This is shamelessly plagerized straight off the Mannlicher Collectors website/Characteristics:
1924/1925 .30-06, 7x57, 7x64, 8x57JS, 8x60S, 9.3x62mm, 10.75x68mm Straight Butterknife Wing Safety carbine, rifle, and takedown steel plate with trap
1950 6.5x54mm, .257Roberts, 270 WCF, .30-06 US Straight Butterknife Wing & Side Carbine & Rifle Plastic
I have been saving my lunch money for a little over a year in order to purchase a nice M-S since two of my best rifle crank buddies were showing off their picks from a huge collection being quietly liquidated by a local gun store. Having finally saved up the required number of portraits of dead Presidents, I too headed off to the local gun store. My initial plan was to purchase either a 1903 model in 6.5X54 or a 1924/25 in 7x57 with a slight preference for the later since I have reloading materials for the Mauser cartridge and would not have to start over with a new caliber. As luck would have it there were several 1903s for sale, none of which was even remotely in my price range and nothing available in 7x57 and all I got out of the trip was a good Mexican buffet lunch. As I sat, disconsolate and dejected upon my thick wad of US currency, at home an auction notification showed up on my smart phone. Lo and behold! They were auctioning several M-S rifles that very month! Most were in lots of 2 or 3 which I quickly calculated would sell far above my means but there were two 1924 Carbines listed singly. One was identified as 7x57 and in less than pristine condition, the other was a runway model in a tight swimsuit for sure and was listed cryptically as 7mm. I quickly referenced the website quoted above and then surveyed the online enablers to see if 7x64 brass and dies could be obtained if necessary. It looked like I could get the European cartridge components if necessary and a bid was quickly entered. Every drawing I could locate showed clearly that it would be quite impossible to chamber a 7x57 in a 7x64 chamber so even though the top of the bridge lacked a caliber stamp it should be easy to ascertain which round was required by the simple expedient of attempting to chamber a loaded 7x57. An excruciating month dragged by and at last I was notified that my bid had held up and as soon as my money and FFL showed up, the rifle was mine. The invoice arrived the next day and my heart nearly broke my front teeth when I saw that auction fees, shipping and insurance had added another $600 to the bill but I'd had five additional weeks to add to the toy fund so no divorce lawyers would be involved in this indiscretion. When it arrived I quickly executed my expedient chambering experiment and a 7x57 with a 140 gr spitzer bullet fit the magazine and chambered without resistance. A couple of telephone calls to shooting partners and I was off to the range. My gunsmith and my very knowledgeable shooting buddy both agreed that this was perhaps the best looking M-S carbine that either had ever seen and that it appeared in every detail to be a first year 1924 carbine based on having a low 3-digit serial number and the appropriate Stoeger imprint on the magazine plate with the correct for the time address. I loaded a single 7x57 and aimed carefully at a paper target set at 50 meters. The shot was great, recoil was pleasantly mild and straight back so that I was still on target. There was a problem with the target though, the hole was missing! I was using the lowest setting of the folding leaf iron sights, no excuse for missing the paper. When I opened the bolt there was a surprise there:
https://i.imgur.com/7CDwYA1l.jpg
We folded up camp and went to my gunsmith's shop to cast the chamber because this clearly wasn't right. It's sort of a process to get the wood off, first you have to remove the magazine, unscrew a wood screw that holds the back end of the trigger guard, unscrew the threaded forend of the trigger guard, then remove a front and a rear stock screw. When I pulled the wood off neither my gunsmith nor I could believe our eyes. Rollstamped on the bottom flat of the barrel was the gunsmith's name and 270 Winchester! Turns out the brass was pretty well fireformed had the neck not split trying to fill the 6mm of additional body which left about 1mm of neck in the new case. Amazingly, the case had sealed the chamber well enough that even with the split neck there was no gas relief into the magazine nor back through the bolt and examination of the primer actually looked like there had been fairly low maximum pressure. The cup and core bullet left, no one knows where it went. Measurement of the bore disclosed a standard .2775 bore and a Go + .002 headspace.
The process employed here cannot be recommended. There was a 100% case failure and the resulting neck is too short for reliable bullet retention. Not to mention that there is potential for catastrophic damage to the firearm and personnel in the area should the case not fully seal against the chamber. 270 Winchester cases are readily available, rendering attempts to create them from 7x57 superfluous.
9 Attachment(s)
M1924 Mannlicher Schönauer
Quote:
Originally Posted by
rr2241tx
Model 1924 Mannlicher-Schoenauer Carbines were made in 7x57 Mauser for the US market and 7X64 Brenneke for the European market where it was illegal to own rifles in military calibers. This is shamelessly plagerized straight off the Mannlicher Collectors website/Characteristics:
1924/1925 .30-06, 7x57, 7x64, 8x57JS, 8x60S, 9.3x62mm, 10.75x68mm Straight Butterknife Wing Safety carbine, rifle, and takedown steel plate with trap
1950 6.5x54mm, .257Roberts, 270 WCF, .30-06 US Straight Butterknife Wing & Side Carbine & Rifle Plastic
The M1924 Mannlicher Schönauer was originally chambered for 'the U.S. 1906 Cartridge' (.30-'06) only.
They were manufactured for export to the United States via the Sequoia Importing Company of San Francisco, California and Detroit, Michigan. Sources differ regarding how many were made, several say 1,000 were ordered but that far fewer were actually manufactured for and shipped to Sequoia. The M1924 and subsequent models of Mannlicher Schönauer rifles and carbines differed from the previous models as they had longer 'actions' (to accommodate the .30-'06) and a retaining ring was added to the Schönauer magazine that was lacking on the M1900, 1903, 1905, 1908, 1910.
Attachment 240719
They did not sell well, and many were returned to Steyr where the M1924 designation was ground away and replaced with a stamping of 7.62X63, the metric equivalent. Steyr continued to manufacture MS rifles and carbines (stutzen) on the longer actions, and did so in several metric chamberings which were stamped in the same location as the model designation had been on previous models. These are what collectors today refer to as 'M1925', and Stoeger sold as the 'High Velocity' model when they became the sole U.S. distributor of the Mannlicher Schönauer.
Attachment 240723 Attachment 240729
Original M1924 Sequoia, Kal 7.62X63 restamp
It should be noted that the previous models were all caliber specific and used Mannlicher Schönauer proprietary cartridges. All M1903 (as well as the prototype M1900) were chambered for the 6.5X54MS, M1905 were 9X56, M1908 were 8X56, M1910 were 9.5X57, AKA .375 Nitro Express Rimless.
Attachment 240725
Here is a page from the 1927 Stoeger catalog, notice only the M1903 through M1910 were offered by Stoeger at that time.
Attachment 240724
Here, from the 1939 Stoeger, the so called 'M1925' is offered as 'High Velocity'.
Calibers of .30-'06, 7X64, 8X60, 9.3X62, 10.75X68 are available:
Attachment 240726
And a (German) WUM catalog of about the same time,
listing the 7X64, 7.62X63 (.30-'06), and 8X60:
Attachment 240727
Here are pages 50, 51 of the 1939 Stoeger catalog:
Attachment 240730
Attachment 240728
