I have a G33/40 (from our very own infamous AlvinMack) that I am having turned into a top notch custom rifle. The action appears to short for a 30-06 length of cartridge. I would like a bit more pop then the standard 7X57 so am thinking an improved version of that cartridge.



What do you think? Pluses and minuses? Also what would it take to make the improved round feed properly?

Give some thought to the 7x64. I have a small ring Brno 22f in that cartridge, and it fits the mag box perfectly. You will not need to modify the feed rails, and factory ammo in readily available.

Isn't that a 280? A factory 280 with 140's will just fit now.

Howard

Finally I can speak from some experience. I have two of those actions. Both with their original 8mm barrels cut down to 20 inches. One the wife took from me and won't give back. The other doesn't yet have a stock on it. Both work beautifully with the cartridge they were intended for. (I know, thats no great news). But if they cycle so good with an 8 x 57 cartridge I don't see why they wouldn't do well with a modified 7 x 57 cartridge.

I also have a fairweather friend who has one barreled in 25.06. I don't know what he had to do, if anything, to the rails. But I do know that he put a Blackburn Box on it, and that he lengthened the opening in the bottom of the receiver to accomodate that box. It cycles and shoots very well.

Make sure and come on and show us the "project" when you get it done.

Blue

My concern with the feeding of the "inproved" is there is much less taper in the cartridge, which from my understanding can play havoc with the feeding as they come off the rails.

Howard, you dip stick, leave it alone. The 7X57 will kill anything you want and do it with style. And YOU will have to fireform all that brass, buy a different set of loading dyes and the gain will not be worth it. A dead mule deer won't know the difference. You can shoot factory ammo in it but it will not shoot as well.

You can't go to a 7X64 without drastically changing the magazine box.

Howard,



The 7x64 was the original 7x57 "improved." It dates back to WWI and has been in steady production ever since.



The .280 is the ballistic equivalent, but was designed around the .30-06 case.



I have a tendency to associate Euro cartridges with Euro rifles, and US cartridges with US rifles. It keeps thing simple for me.



Chick,



What modifications would have to be done to mag box? The cartridge seems to fit fine in all of mine, and they are original 98 length.

Howard, I went to some other sites to see what this Ackley Improved 7 x 57 is all about. It isn't very different at all from the 8 x 57. I am looking at the standard Mag box as well, and I don't see where it would be a problem.



BUT I agree with Customstox. Gosh, both the standard 7 and 8 mm mauser can be handloaded to standards where any deer size game is not going to know the difference. Heck, if it has a good factory 8mm barrel on it I would have it polished and leave it as it is.



Blue

Howard,

I'll have to second what Customstox said. I have three M98's in 7x57, just dressed differently.

Dressel's has a beauty for sale in .270. Nice photo layout.It comes with Blackburn bottom metal.

Blue,
G33/40's came with a 19" barrel. See site M98.com/g33/40/

Bob

Manhasset



By golly, you are right. I never measured them before. I jsut measured now and the one I have (dot 7,88, 1941) is exactly 18 1/2 sticking out of the action. I don't know what the wife's is, but its about the same. I always thought they were 20 inches. They were that way when I bought them, and I always thought they had been cut down!



Blue.

If it matters, the last time I checked RCBS's die listing, they wanted over a 100 bucks for the dies.

KurtC, if you say they will work, I would accept that. You have a great deal of knowledge about these and I was just making an assumption. I am not much of a wildcat fan and was fishing for more excuses, lol.

Howard

Its not a great collection. All I have left are five 09 argentines, one 08 Brazillian, and 2 G.33/40. I just sold two small ring mexican's this past week, and another small ring mexican about a month ago. I started my interest in them way back in 1975 and have bought a ton of them, but also sold them because I have always been broke!!!
I wish I had one third now of what I have had in the past.

But don't we all!!!!

Blue

too bad I didn't know about the Mexican

Howard

the one had the springfield type striker knob, and the other two had the regular looking striker knob.

Blue

Did Styer make a G33/40? I think I saw one on a used gun rack for $395. I'm not a muaser guy but something clicked. I came and checked here to see if it was desirable. Called back but it was gone.

Thanks for replying Chic. You sent me into a panic trying to figure out what I was missing all this time. As a side note, I once thought that the 7x57 and the 8x57 were based on the same case. When I actually compared them side by side, I couldn't believe the difference.



The 7x57 is one of my favorite cartridges, but it seems wasted on a full size 98 action like the 33/40. You have about 1/2" extra magazine length that cannot be filled with even the longest 7mm bullet (Barnes used to make a 195 gr, but has been discontinued for some years). The 7x57 is right at home in the intermediate actions, such as the Mexican, the FN-24 or the Yugo 48.



The 7x64 fits with a bit of clearance, the .280 is actually too long but fits with shorter bullets.



The 8x57 however, can fill a standard 98 magazine if you use 220 or 250 gr bullets.



P.S. I never saw a need for an Ackley-Improved anything as well. Just about every cartridge niche had already been filled by the 1920's. The rest has been pretty much redundant.



Dempsey,



Only the Czech DOT factory made the 33/40, for the Germans during WWII. The Steyr rifle you saw was probably a Kar98 from WWI. It had a small ring, but large ring threads. This doesn't leave much metal in the receiver ring, and the metal than was not as strong as in the post-war years. The 33/40 had a small ring and small ring threads, plus was made with more modern steel.

Howard

One more vote for the plain vanilla 7X57. While you are at it, stamp the caliber 275 Rigby!!

It is all a person needs in a round that shoots a .284 bullet. I get over 2850 fps with a 150 grain Nosler and could probably get 2900 plus if I wanted to. 2700 plus is easy to obtain with the 160 grainers in my rifle. For the extra cost in dies I can't see going to the improved case.

Also from my experience the biggest gain in Ackley improved rounds are seen with heavy bullets within the caliber size. If I'm not mistaken you already have a 7mm Mag to do that with .284 bullets.

I agree with Kurt, the 7X64 would be the only other choice of mine if I bypassed the 7X57, which I wouldn't.

Howard,

I have to say from experience with improved cartridges, that they can be a pain in the butt if you aren't into the whole fireforming process and what not. That said, I know somebody who had a 7x57improved, my stepfather's brother, and Jerry (stepfather) did the loading for it, performance was great. So great in fact that the barrel got shot out! :-) So if it were my I might consider it, but I have the dies sitting in my shop already. If I didn't already have the dies for it I would go with the standard and I like Idared's idea of the 275 Rigby nomenclature (didn't Bell use one of those?)

since Chic is so against it I would make him a deal, you won't Ackley Improve it if he checkers the stock for you!

Sometimes Improved cartridges are good, of the ones that do benefit enough to make it worth doing the 257 roberts and 7x57 might be the best. I have a 35 whelen ackley improved that performs real great too. my 06 improved though is going to become something totally different, disappointing bastard.

Red

Red, checker the stock??? I will be building it.

Idared, the 7X57 Rigby is not the same as the 7X57 but they are similar. I don't know the history of the .275 other than it came out in 1907 and the 7X57 in 1890 and the .275 has less capacity by about 0.7 grain of water - no big deal. Can see Rigby "inventing" a new cartridge though. Looks like they came out with dumb ones even then.

Howard,
You want more pop than a standard 7x57? Isn't your 1909 a 7mm Rem. Mag? I think you are over thinking the issue. Probably worn out from all your campaigning for Al Sharpton. Tell you what, I'll trade you for a Model 70 .375 that I can't get to shoot worth crap. One other note. By keeping it a standard 7x57 you can just borrow ammo from Chic or me.

Jeff

Well, it should be great!! My standard 7X57mm Ruger No. 1A will fire a 175-grain Nosler Partition @ 2720 FPS, with MOA accuracy. I believe this equals, well, at least, a FACTORY LOADED .30/'06 any day!! The IMP version should do better!

Howard,

I will cast a vote for a 7x57. Specially if you dont have one yet. Everybody needs one. The 7x57 Ackely(40 degree shoulder) is a good cartridge. The first rifle I ever built was chambered for it and I shot the bejesus out of it. You will need to have the feed ramp modified and maybe a little rail work done to get it to feed properly. It will feed if left alone but it will play hell with your brass. If I had to do it over again - I would skip it. Like Chic said, you gotta buy special dies, fireform etc etc....

But on the other hand if you did build the Ackley version you could still bumb rounds from Jeff and Chic. Then givem back the empties just to irritate them. LOL

MHO, no it is close. Here are some dimensions from the handloaders manual on cartridge conversions. 7X57 measurements will be first followed by .275 Rigby.

Dimension 7X57/.275 Rigby
length of case 2.235/2.24
length to the shoulder 1.752/1.77
width at the shoulder .431/.428
length of the neck .340/.320
shoulder angle 21.04/19.12
neck diameter .321/.325
shoulder length .143.150
head diameter .471/.475
rim diameter .473/.475

With a tight chamber, I do not think that either one would fit in the other.

I'll be damned! Seems like you live and you learn!
- mike

Chic, if you are building the whole stock then I think he might just be stuck with the standard 7x57 huh! :-)

I will say that a light weight 7x57 is a joy to shoot. My stepbrother has one in the Winchester featherweight (pushfeed version) and that thing is just a pleasure to carry (which is why he seldom lets me trade my heavy 03a3 06 for the very long)and is a great little shooter. What are your plans for barrel lenth, contour, stock shape and etc.?

Red

Red, the thing is, it is already a 7X57. Don't mess with success.



I think he said he wanted a thumb hole stock with inlays on the sides and an inlaid compass. Nice touch .......... guy has no taste.

Chic,



What about using 1909 Bottom metal and going with a 270 Winchester. G33/40 Bottom metal just doesn't do it for me unless you paid to have the bow reshaped. While I think you can't go wrong with a 7x57 I just brought that up as a better option. All I can say is I'm glad that we talked Howard out of making that a 257 Weatherby.

Gents: Particularly, Chick. I got this here now book from His Majesty's Printing Office (UK) probably before some of you were born, which is easy for me to say. It is called the British Rules of Proof. It lists a ctg. called the
.275 H.V. Rigby, Directly under that listing is one called the 7 m/m Mauser. The one called the Mauser translates into the use of same headspace gages as what we and C.I.P like to believe is the 7 x 57. Matter of fact the dimensions for both of these ctgs. is identical including the proof pressure which is listed as highest mean service pressure, 18.5 Tons PSI measured at the base with copper crusher measured with a special bolt head and we like to think is the pressure transmitted to the bolt lugs and seats in British Long Tons. There is a politicians way out on this, I suppose you could say that the identification in the reloaders manual for one or the other if not both was a different ctg. (s) altogether. I personally think that they are the same. Maybe like the .280 and a seemingly interchangeable round called the 7m/m Express{?) Taking a 7x 57 hunting south of our border , when that wasn't foolish wasn't possible, but a .275 Rigby was a piece of cake- figuratively speaking. Just make certain you have properly headstamped ammo to go with it or so I was informed.

Tom, thanks for the tongue in cheek, lol. I had always thought the same thing. I just happened to look at this book as it has all the names the cartridge is also called. Under .275 Rimless (Rigby) under other names it said .275 High Velocity Rigby. Under notes it said "Similar to 7 x 57". It has a reference for it under Cartridges of The World pg 227. All the dimensions that are listed are very close but not matching. Your book has all the dimensions being the same. I am as confused as ever it seems. I do appreciate the information. I will continue to wander about in the fog, being happy that I can at least identify poor visiblity. I suspect that I just found another major error in this not so old book. Of course I have to make the mistake of quoting it. That makes the fog a bit clearer as I step of a cliff.

Brad, he doesnt have it anymore. Someone stole it from One Shot Firearms today. Nasty business, he can't trust anyone. lol

Standard, history and class wins with me. The 7x57 is a great cartridge.

22 inch barrel 1/2 round 1/2 octagon, in a lighter contour, but no light weight.

Oh, you had to go throw the 1/2 oct. in there, now I am going to have to start envying you. Unless of course you really want a compass in the stock, then I guess I wouldn't want it (or are we talking a small compass I can ignore) :-)

I am willing to bet that discrepancies happen more often than most people catch as far as cartridge dimensions and other measured data goes. I would think that over time gunsmiths didn't always do things "just so" and that some of the cartridge designs may have been considered "flexible". What I am thinking is that maybe with certain cartridges a person found an example rifle, examined the gun, cast the chamber, looked at fired rounds, and then drew out the specs, not knowing that the gun was not cut to the original dimensions to begin with. I mean hell, I read an article posted here about the 375 whelen and headspace trouble, and that the "original" design didn't have that trouble, it was a subsequent deviation that gave the bad rep of not headspacing properly.

so Tom, must be nice to have that huge reference library. Now I am going to go and look at my old cartridges of the world and see what it says. mine may be an older edition than yours Chic.

Red

It could if it was written in sanscript on a stone tablet

Jeff