Cartridge Discussion: The 7X57
Here's a real winner in my book. The grand ol' 7X57, .275 Rigby , or 7mm Mauser. It's been called by several names through out it's very long history as a metallic cartridge, available first for military usage and then as a sporting round. It's been long used for both purposes all over the world.
115 Years Young
This is one of our very oldest small-bore smokeless cartridge developments. Developed by Paul Mauser and introduced in his Model 1892 Mauser bolt action, a rifle similar in design to the Model 1889 Belgian and Argentine rifles. Beginning with the introduction of the Model 1893 Mauser with its staggered magazine the cartridge became quite popular as a military round, especially in Latin American nations and some European nations. Spain was a buyer for the 93 Mauser design with its 7mm cartridge. The 93 Mauser could be considered state-of-the-art for an infantry rifle in the last decade of the 19th Century. As a repeater it could be manipulated rapidly. With its charger loading system it could be reloaded rapidly hence the rifle could maintain a rapid rate of aimed fire. Both the British troops and American troops were given an education in the effectiveness of the 7mm Mauser cartridge and the various Mauser rifles for which it was chambered. The British suffered under the application of the 7mm in the Boar War. The Americans took their dose during the Spanish-American War.
The cartridge benefited from advancements in smokeless powder from its beginning. Original ballistics of the Spanish 7mm cartridge have been variously quoted as either 2100 fps or 2296 fps with a 173 grain full patch round nosed bullet. As more efficient bullet shapes evolved the 7mm benefited greatly and continued to shine as a outstanding round for the arming of a nation's troops. I think it'd still be a good choice.
A Rich Hunting Tradition
It soon became popular as a sporting cartridge among European hunters. Many were taken to African colonies administered by Germany. In 1907 Rigby appropriated the cartridge, terming it their .275 Rimless High Velocity. Everyone knows of the prowess of W.D.M. "Karamojo" Bell who made extensive use of the 7mm cartridge in its .275 Rigby guise to take a great many elephants during his ivory hunting days. Known by his "African" name not too many may know his name as Walter Dalrymple Maitland Bell. Bell also favored an even lighter cartridge for ivory hunting use, the 6.5X54 Mannlicher Schoenauer. Neither of these cartridges are heavy game rounds by any stretch of the imagination and their successful use by Bell and a few others was a matter of precise shot placement to the brain and luck. I had the privilege of reading a borrowed copy of Bell's "The Wanderings of an Elephant Hunter" many years ago. I thoroughly enjoyed it and have been looking for a reasonably priced copy for my library ever since. Ebay has denied me this opportunity with the increase of prices it seems to generate.
Some of My Efforts With the 7X57
This is one of my favorite rifle cartridges. I've taken a decent amount of deer with the 7X57 using bullets in weights from 120 grains to 154 grains. My Interarms Mark X Mauser is easy to handload and rewards most efforts with outstanding benchrest accuracy. In fact the most accurate five-shot group I've ever fired from a centerfire cartridge larger than .223 from the bench rest at 100 yards was with this particular 7X57 rifle. It measured .62 on an inch. My 7X57 rifle wears an old Lyman 6X All American scope. The first couple of deer were taken on a deer lease I shared with my brother-in-law back in the mid '80's just west of Brownwood, Texas. Our dads were both on the lease with us and I'm grateful to have known his father and hunted with him. One of these deer was taken with a 145 grain Speer bullet and the next one was taken with a 120 grain Sierra.
I later moved onto a deer lease in Coke County, hunting there for some 6 seasons. I took several deer using the 145 grain Speer bullet and then got to playing with the 154 grain Hornady Spire Point. It was with this bullet that I fired the tightest group ever. One of the few times I ever threw caution to the wind, I blatantly overloaded the cartridge with this bullet using IMR4831. The Mark X rifle was offered in several chamberings that operated at significantly higher pressures than the SAAMI standard for the 7X57. I reasoned that the cartridge case was much the same as a .270 Winchester in construction, likely was formed from the same brass "button" in the factories, and the rifle was of modern construction. I'd load a few, fire them out the back door, come back in and check bolt lift, measure case heads, and observe the primers. After repeating this procedure I ended up several grains of powder over maximum without any pressure SIGNS or sticky extraction. I decided to quite while I was ahead. I'd made a "7X57+P or "light magnum". I took the rifle and a few boxes of this ammo to the range and shot the nice group. Ten rounds over the chronograph revealed an eye-opening 2784 fps with 2651 foot-pounds of energy. Considering the ballistic coefficient of the long .284 diameter bullet it would shoot flatter than a .308 with 150 grain bullet and arrive down range with more punch. I can't recommend such seat-o-the-pants handloading practices. I've only purposefully exceeded loading data twice. Once with the 7X57 and once with the .30-06.
I took a couple of bucks on the Coke County lease at ranges of less than 100 yards with this load and it performed well. The deer dropped like rocks and expansion was about perfect. Then I made a couple of long range shots on deer. The performance wasn't so fine this time. One deer shot at 190 yards led me on a merry chase trailing an ever decreasing blood trail over the fence to the next ranch. I finally caught up to him, stone dead, a long way from his position when the bullet struck him. He was holed through the lungs but it looked as if he'd been run through with a rapier.
Later that season or perhaps it was the next season I positioned myself at the edge of the center of a field that was approximately 640 yards long by 200 yards wide. From my shooting position I could cover this field and likely not exceed a 300 yard shot by much. I recall that it was the closing weekend of the season and I had a doe tag to use. Just before dark a doe ventured out onto the short green winter wheat across the field from me. She dilly-dallied and wouldn't come any closer and I was losing light. I squeezed off a careful shot and she began running diagonally across the field towards my side. She was really stretched out, running full tilt. I rapidly worked the bolt and shot a second time. She dropped at this shot. Upon investigation while field dressing the deer I found a clean hole through the lungs. It was as if she'd been poked with a pencil. I was chagrined when I walked up to her to see a hole in her paunch. I hadn't field dressed a gut-shot deer in years and wasn't looking forward to it now. Upon opening her up I was delighted to find that the bullet had only poked a small hole through. No messy guts and smell to deal with. Great! I reasoned that the lung hit was the first shot and the paunch hit was the second. While field dressing her it occurred to me that perhaps that 154 grain Hornady was a bit tough for use in the 7X57 as it wasn't opening up at anything but short range. The last couple of deer I've taken with the 7X57 have been with the Sierra 140 grain spitzer boat tail bullet with good results.
100 grain Sierra spitzer HP, IMR 4064 MV 2954 ME 1938 ES 28
120 grain Sierra spitzer, IMR 4064 MV 2393 ME 1526 ES 45 (light target load)
120 grain Sierra Spitzer,I MR 4895 MV 2981 ME 2363 ES 51
120 grain Sierra Spitzer, IMR 4320 MV 3076 ME 2516 ES 44 (deer taken)
140 grain Sierra Sp BT, IMR 4320 MV 2739 ME 2332 ES 42 (deer taken)
145 grain Speer spitzer, IMR 4350 MV 2790 ME 2506 ES 36 (deer taken)
154 grain Hornady Spire Point, IMR 4320 MV 2674 ME 2440 ES 37
154 grain Hornady Spire Point, IMR 4831 MV 2784 ME 2651 ES 38(deer taken)
160 grain Sierra Sp bt, IMR 4831 MV 2616 ME 2428 ES 45
160 grain Sierra Sp bt, IMR 4320 MV 2590 ME 2385 ES 28
175 grain Remington round nosed soft point, IMR 4320 MV 2557 ME 2537 ES 10
175 grain Remington round nosed soft point, IMR 4831 MV 2408 ME 2254 ES 62
Interarms Mark X 7X57 with 24-inch barrel used for testing
Oehler Model 12 Chronograph
I'm generally not in favor of giving exact charge weights of powder in a forum format. PM me for further information.
The 7X57 has been crowded by a number of similar cartridges since its birth in the closing decade of the 19th century. Some of the best ones are the .260 Remington, .270 Winchester, and .280 Remington. In field use it will hold its own with any of these newer offerings and it won't subject its user to a beating. It offers great ballistics for anything up to elk in my view. Mind you I've not taken elk. I feel that it gives up little if anything to magnum cartridges under .30 caliber. It once was considered adequate for all species of North American game and for African plains game. For all his reputation for praise of the .270 Winchester Jack O'Connor and his wife Eleanor made a lot of use of the 7X57 for their North American hunting trips. It is just as useful as ever and when one chooses the 7X57 as his hunting cartridge he is carrying round that possesses a wealth of tradition and far-flung experiences.