308 Long Neck?

[GrizzLeeBear]

Its late, but I have had this idea bouncing around inside my head all day, so I thought I would see what you all have to say about it. Heres the idea. Run a 7mm or 8mm Mauser case into a 308 sizing die. Viola! a 308 with a long neck for shooting big 180+ grain cast bullets without pushing the base of the bullet below the base of the neck into the powder space.
Ok, now for the reason why. I have been wanting to get back into rifle silhouettes, but I would need to do it on a very tight budget (which is the main reason I got into casting). Building or buying a good quality commercial rifle and buying lots of match quality J-bullets just isn't in the cards. I have a nice Steyr 1912 Mauser that was rebarrelled by NATO to .308 that shoot cast bullets really well, but I am NOT going to hack it up into a sporter & put a scope on it, It is far to nice as it is. My dad has a couple of good Mauser actions that he got years ago intending to build some rifles with and I would be able to "beg" one off him. He also has some 8mm and .308 NEW, never installed stepped military Mauser barrels and I'm sure I could get one of these also. Putting these together and dropping them into one of the "drop-in" composite stocks should be relatively inexpensive. I think it would be neat looking rifle too.
Looking at the charts in the back of the Lyman Cast Bullet handbook, it looks like you need to get a 190 - 200 gr. bullet going about 2000 fps to have it stay supersonic at 550 yds (500m). The .308 data looks like it should be able to do this readily with a number of powders. With the longer length of the Mauser action, there is no reason to push the bullet down into the powder space, except for that short neck on the .308, sooo.....
My thought is to have a .30 cal. neck reamer run in to give a case length the same as the Mauser case, but leave the body as is. This would allow you to form and load this "wildcat" using .308 dies. Well, I just had to try it. I don't have any Mauser cases, but I do have some .257 Roberts brass that I use for my 6.5x257. I ran one over a 7mm tapered expander from a 7TCU die, then into the .308 FL die with the expander removed, then thru a .30 neck sizer die with a tapered expander (lubing the case at each step, of course). It worked like a charm! I got exactly what I wanted, a .308 with a long neck. Of course, this would still need to be fireformed to make the Mauser tapered case fill out the the straighter .308 body taper.
I have some .30 cal. cast bullets I got from my dad years ago, but the biggest one is about 185 gr. RN. I don't think its a Lyman, but it is a bore riding design similar to a 311291 with a little longer nose. I seated one in this new case, with the top of the front driving band just above the mouth, the base of the bullet is still in the neck with a little room to spare and a COL of 2.780. Even though this would still be under the .308 max. OAL the long neck covers all the grease grooves and I'm sure would give the bullet more support as it starts moving. However, the idea is to allow longer bullets to be seated to a COL length that exceeds the max. 308 length. With this long neck it looks like you could easily seat 200+ gr. bullets above the powder space with room to spare in a Mauser action.
I'm sure this has been done before, it seems too easy and makes too much sense. So, anyone else have a .308 Long Neck? Actually if I do this I will have to name it something like".308 LNM (Long Neck Magnum) right? Don't all new cartridge names have to have "magnum" or "express", etc. in the name? LOL

[Char-Gar]

The long neck 308 was invented in 1894. It is sold under the name of 30-40 Krag.
The case capacity is virtually identical with the .308 and has that wonderful long neck.

That said, the notion of a long neck .308 has ran through the brain of many of us. Most of us "got over it", but using a bullet like the RCBS 165 Sil that contains the base in the short neck of the .308 case...or...we just let the bullet dangle it's feet in the boiler room and pretend it doesn't matter. We are not deluded, as it really don't matter...much.

I am late to the 8 X 57 game, and many others have far deeper experience than I do with the round. But, I am finding out that those rifles with the deep rifling grooves will really do well with cast bullet. I wish the rifling twist was slower, but the world is full of compromises.

I bought a minty CZ/Brno made Persian 98/29 barreled action and have made it up into a sporter and I am delighted with it's ability of shoot cast bullets.

[357maximum]

As said above alot of us have had similar thoughts/notions and ideas. I have wanted to do this in 358win LN for awhile, but funds have prevented such an escapade so far.

Some recommended reading:

http://castboolits.gunloads.com/showthread.php?t=13778

[Phil]

You're overthinking this and running into way too much time and expense. I'm guilty of the same thing (:>) in lots of cases though. What you need is just a throating reamer for the 308. Put the throat where you want it and you're done. No messing with cases, dies, and all that.

The principal problem that I see with running 8mm cases into a 308 die is this: all rifle cases have tapered walls. When you run a long case into a FL die to push the shoulder way back, you start to get into thicker metal pretty quickly. BTW, even the neck of a factory case is tapered a bit. But if you push it what happens is that you now have a long neck and it may or may not be straight (not tapered and not eccentric) on the inside. So you seat your bullet in the case and chamber it. The bolt may or may not shut. Depends on whether or not you have enough neck clearance built into your neck reamer. If there is only a slight interference you might not even really feel it as the bolt shuts. But, now you have an interference fit in the neck and that ain't good. If you want to do this its really best to turn the case necks in the process. I know about this because of lots of heartache in trying to make it work on a couple of different projects. There is a much better solution, but it requires a tight neck chamber reamer and neck turning. The best and cheapest solution remains just rethroating a standard 308 chamber. And even that requires a skilled machinist, a lathe, and a good dial indicator if ACCURACY is the goal. I know what your thinking is but the fact remains that the standard 308 has been shooting better than most of us for a long time now.

Cheers,

Phil

[mike in co]

another option with all thos bbl's available...go with an 8mm, the lee 175 works well. consider a throater to move the throat out is necessary.

i use striaght ww h2o dropped, and can hold the 10 ring at one hundred on a
sr-21 target.

maybe add lino to go out to 2000 fps, good fit, and good lube...

[GrizzLeeBear]

Great input, thanks guys!

Chargar, yeah I have noticed how much this case looks like a rimless 30-40. Since the RCBS Sil bullet is only 165 gr. any idea how fast you would have to launch it to stay supersonic (+/- 1100 fps) at 500m?

357maximum, thanks for the link, lots of great info. Jeez, that discussion happened only a few months ago and I missed it. Whats funny is I started out calling this the .308 LN (long neck) and after posting last night thought that .308 CB (cast boolit) might be a neater title. In the other thread Molly started out calling it the .308 CB and latter talked about naming it the .308 LN instead. Go figure?

Phil, about the neck thickness, I did some more measuring. My dummy round with the 185 gr. bullet seated with the base of the bullet at the base of the neck, measures .334 (which is identical to a loaded round for my Steyr Mauser). The neck of a fired .308 case from my Steyr measures .345 so it looks like there isn't much neck "thickening" going on when pushing the shoulder back and there is plenty of room for the case to let go of the bullet. We are only talking about pushing the shoulder back about .185 so its not down into the thicker part of the brass apparently. However, I used a .257 case and necked it up ( a 7mm case would probably be about the same), but necking a 8mm down may cause it to have a thicker neck. But with the measurements above, it looks like these military chambers are generous enough to allow a little thickening to happen.
As you said though, just using the standard .308 and throating it out a little (or not) may work just as well. Looking at the data for 175 - 185 gr. bullets, most of them would stay supersonic at 500m if started out at about 2100 - 2200 fps, which the .308 can do easily. I looked at my info. for the Steyr and my max. COL with the 311466 bullets that I have is 2.790 (seated to the lands). The 311467 is just the same bullet with two more lube grooves and about 178 gr. I don't have any of these but it appears that it would seat at that length and have maybe just the gas check below the base of the neck. I also think the 311334 might work about as well.

Mike, I thought about the 8mm, it would work well enough, but I already have dies, brass and one rifle for the .308 already. I don't have enough time to cast as many bullets as I would like for the calibers I already have now.

My concern with the lighter (165-185) gr. bullets is that I have read that even though the the 308 can shoot them up to 2400+ fps, many of you report that accuracy falls off above 2000 fps. According to the Lyman data, these bullets started at 2000 fps will go "transonic" at about 400m. Where the 200 gr. bullets will just stay supersonic all the way to the target (and have more momentum to knock down stubborn rams when it get there). I think the long neck would be a better case for the long 200+ gr. bullets.
I think the answer here is to start out with standard .308 with the "lighter" bullets. If I can't get the accuracy at the velocity I need, then try the 200 gr. bullets in it. If I run into problems with seating depth etc. with the heavies, then have the neck reamed to the Long Neck. That way I don't have to pay for the gunsmithing and do all the case forming unless the lighter bullets won't work.

It does look like a cool case though. kind of "retro" (compared to the newer short neck cases) with that long neck and a big cast bullet.

[Phil]

I have a 311334 mold and use it works well in K-31's because the nose is about .297". You'd have to Beagle it quite a bit to get it up to a size usable in a normal 30 caliber barrel. I kinda hesitate to lap out the nose just because it works so well in the Swiss. I have always wondered if the newer molds cast a bigger nose. If so, it would be a GREAT bullet in the 30 calibers.

Make sure if you do ream the neck that the reamer is at least the same size as the existing neck or you wind up with funny looking cases.

Cheers and good luck,

Phil

[Char-Gar]

I don't shoot cast bullets are 500 meters and don't keep those kinds of math figures in my head. If I were going to shoot cast bullets at 500 meters, I would go with a longer/heavier bullet, something in the 200 to 220 grain range. The increased sectional density would help it maintain it velocity at longer range, even though it starts out slower.

[shooter93]

357 Maximum....If you're thinkingg about the 358 Win just neck the Krag to 35 cal. I have one that I'm playing with and it shot 225 gr jacketed bullets so well I'm having another pipe made for just cast bullets and getting the reamer ground for a perfect fit to that round. Redding made the dies for a couple of these so far and I'll have them make 2 sizing dies for this one.

[Hamish]

There really is nothing new under the Cast Bullet Sun,,,,,,makes me wonder where the Krag would be now if they had been able to push it to modern .308 levels,,,,,,

[Idaho Sharpshooter]

It would be a fun experiment, and you are only really out the cost of a reamer. I have run a few 8x57 cases thru a 308 FL sizer die just to look at. My thought was to use the Loverin style bullet, and see if it would shoot more consistently/accurately if the entire bullet were inside the neck instead of dangling down in the case body. A hundred NORMA 8x57 cases, so you have match grade cases, and a reamer cut to match the formed cases, and let the games begin...

[Larry Gibson]

I had the same thoughts years ago back around '80 or so. Except I though of just using the .308W case and pushing the shoulder back so the neck is '06 length and case capacity was about the same as the 300 Savage. With IMR 4895 at close to100% load density under a 311284 the velocity should have been 2000 - 2100 fps. I had a brand new 2 groove '03A3 barrel which was touted as "ideal" for cast bullets. Had the barrel put on a Mauser action and began testing. I could indeed get 2000+ fps but like the '06 and other 10" twist barrels best accuracy is still down in the 1600 - 1900 fpsrange. I still have the rifle and call the cartridge the .308 CBC. Pictured is the .308 CBC next to it's parent, the .308W.
Suggest you check out the 30 original 30x57 concept thread at; http://castboolits.gunloads.com/showthread.php?24903-30x57-amp-35x57 (http://castboolits.gunloads.com/showthread.php?24903-30x57-amp-35x57)

The basicconcept was;

Based on a couple posts I made in other threads several members have PM'd me for more info on the two cartridges I mentioned for cast bullets in Mauser rifles. These are the 30x57 and the 35x57. Both are made from 8x57 cases by simply FL sizing them in the shortened'06 or 35 Whelen die. They can also be formed from '06 or similar cases which allows customizing the case to fit the chamber.

These two cartridges have 5 major attributes;

First is the case is perfect for Mauser actions. The length is correct allowing for heavier bullets to be used without seating them below the case necks. The case taper is the Mauser taper that the magazine and feed rails are made for, hence they feed slicker than the scum off a Louisiana swamp.

Second is case capacity; It is just slightly more than a .308/.358 Winchester so with correct medium or slower burning powders loading density is close to 100% when using medium and heavier cast bullets in the 2200+ velocity range.

Third is; The long '06 length neck. This allows most bullets to be seated to the base of the neck and the lube grooves are covered. Also the longer neck gives additional support to the bullet during initial acceleration.

Fourth is; the ease of which cases are made and the fact that regular dies are used.No special custom dies are required. I shorten the dies .288" for both cartridges. With both the FL and seater shortened you are set to go. Though I'd also use a shortened NS die.

The fifth attribute is in chambering; I shorten the dies and form 3 cases. These are used as headspace gauges. The barrel is then chambered using standard '06 or35 Whelen reamers. A tight neck match reamer for the '06 might be better thoughfor the 30x57. Both reamers are readily available to rent or buy so nocustom reamer is involved.

With your desire to use the heavier bullets I suggest a 12” twist. And yes it does adequately stabilize the longer cast bullets such as the 311284 and 311299. With the 12” twist in a 26” barrel and slower burning powders velocities up into 2200 – 2400 fps with very good accuracy are quite possible.

The 30x57 has recently morphed into the 30 XCB which is gaining some favor. You might check out the thread on that in the "Special Projects" forum. Second picture is of the 30x57 with it's parents; the 8x57 and 30-06.

Larry Gibson

114047 114048

[Hamish]

"Suggest you check out the 30 original 30x57 concept thread at; http://castboolits.gunloads.com/showthread.php?24903-30x57-amp-35x57"
January 2008

Original?

http://castboolits.gunloads.com/showthread.php?13778-The-perfect-cartridge-case-for-cast-bullets-is
February 2007

But then, as CharGar pointed out in 2007, the original "long neck" case of .308 volume was the 30-40 Krag,,,,,,,,,

It continues to tickle my funny bone that technologically we keep ending up back in the Golden Age of Cast Bullet Technology. I've had enough experience with coming up with parallel product discovery in a couple of areas to have realized some time ago that there really is nothing new under the sun.

[Larry Gibson]

The 30-40 doesn't feed in Savage bolt action rifles and very few Mausers.

Larry Gibson

[frnkeore]

The 300 Savage was way ahead of it's time and one of the best chamber designs, even today. it has the bench rest standard 30 deg shoulder but has the drawback of a very short neck, even for jacketed bullets. It does have about the ideal case capacity for a rifle that will shoot both cast and jacketed bullets. It will equal the 308W velocity's with a much better neck and shoulder design if made in the LN (long neck) form using the standard length 308W case. In that form, the neck in the chamber is .376 long, where as the 30-06 neck has a chamber length of .390. Only .024 longer.

I bought a barrel of of Ebay about 2 years ago to do just that (300 Sav, 722) and lengthen the chamber two weeks ago with a PTG 308W Palma, neck and throat, reamer. The Palma freebore and leade, isn't the best for cast bullets but, it's better than the standard 308W throat. The Palma throat has a .3082 freebore and a 1.5, per side leade angle. For a dedicated cast bullet chamber, you would want a throat with a .3085 min. to .3095 max. freebore and a 1/2 to 1 deg leade.

I re-cut the 300 Sav neck two weeks ago and made 20 cases. I will install the barrel on my Remington 660 soon (1 to 2 months) and try it out with jacketed first, as that's what the throat is made for and then try cast.

This is the way to go for you guys that have thoughs 300 Savage, Remington 722's.

Frank

This is my case:
114066

[Hamish]

More interesting history:

http://en.m.wikipedia.org/wiki/Blake_rifle

(partial)

"Blake submitted two of his rifles to the trials,[1] both were chambered in .30 Blake cartridge - a rimless version of the .30-40 Krag cartridge.[3] On August 19, 1892 Army Board recommended the Danish Krag-Jørgensen rifle to be adopted as the new service rifle. American designers were against the Army's adoption of a foreign design. In support of the designers' view Congress demanded additional trials be conducted before any funds were to be authorized for the production of the Danish rifle. The additional trials were not only to include only domestic designs, but also a new board. The new board was appointed on March 1, 1893 and the trials commenced on April 7, 1893. The two rifles were again submitted, the board decided that Blake's design was unfit for military service due to the feed system.[1] Despite the additional trials the Krag-Jørgensen rifle was still favoured over other designs. In 1895 Blake submitted his design to US Navy rifle trials, his rifle lost to Lee's design.[4]"

http://www.thehighroad.org/archive/index.php/t-611898.html&

(partial)

"Both .30-40 rimmed and rimless were developed by Frankford Arsenal during the original Magazine Rifle trials in 1892. US Ordnance decided to go with the rimmed version - and specified it - due to superior extraction with dirty and corroded ammo. The rimless variant fell by the wayside once the US decided to adopt a more powerful rimless cartridge in the .30-03 (forerunner to the .30-06) firing a 220 gr bullet at a (hoped for) 2300 ft/sec. One could argue that the 7.62 NATO would share a lot in common with that .30-40 rimless - very similar case capacity, etc. Interesting alternative history had the rimless been adopted instead of rimmed. Of course - every other country in the world except Germany felt that rimmed was the way to go for a military cartridge."

http://www.jouster.com/forums/archive/index.php?t-25648.html

(REALLY interesting train of thought, partial thread quote)

"What if the Krag had Originally Been Adopted with a Rimless Cartridge?

The history of the Krag rifle's replacements might have been drastically different. Indeed at the time of the Krag trials several examples of rimless cartridges were tested, the 7mm and 8mm Mausers among them. Rimless cartridges were in their infancy, but were truly viable in 1892.


In reading The Krag Rifle Story it is mentioned that concerns over headspace of the rimless cartridge and the rifle chambers swayed the board to recommend staying with the flanged or rimmed cartridge. What we take for granted today- the rimless bottleneck cartridge- scared the ordinance board in 1892.


So, what would have happened if the 30 US or 30-40 as we know it today was originally rimless? Could the ballistic twin of the 303 British have enjoyed the long life as its English counterpart?


How about this theoretical sequence of events;


1- The Spanish American War left the US Army a stockpile of captured Spanish M1893 rifles and ammunition to ponder.


2- The 1899 clip loading evaluation is successful, but not adopted for the Krag. The Mauser system is judged superior. Work begins on a replacement rifle.


3- The demand for a clip fed rifle fueled by the Spanish-American War was met with the 1903 Springfield adopted for use with the 30-40 Rimless.


a) The receiver was overbuilt for the low pressures of the 30-40 Rimless, a fact not overlooked by the ordinance department.
b) The new rifle is well received by the troops. The ammunition is lighter and has less recoil than the experimental 30-03 cartridge that was rejected in the trials. The troops have mixed feelings on the ramrod bayonet system though.
c) The new rifle allowed the use of stockpiled ammo left over from the Spanish American war.


4- In 1905, the Germans adopt the Spitzer bullet of 154 gr in the standard 8x57JS cartridge. US Ordinance dept. takes note that it is not backwards compatible with older rifles. Having just adopted a new rifle, the Ordinance Department concentrates on its deployment.


5- By 1906, there was a large stockpile of 30-40 rimless ammunition on hand. Springfield had completely retooled to build the 1903 and was in full production, it was decided to evaluate other factors before getting on board with the Spitzer style bullet. After all, there is political pressure to not waste existing ammunition stockpiles and there are many Krag rifles that are perfectly serviceable.


6- In 1908, the Russians adopt the Spitzer bullet for their M1891 Mosin Nagant rifles. Unlike the Germans, the newer ammo is interchangeable with the old, save for the rear sight differences due to the flatter bullet trajectory.


7- Bowing to all sorts of pressures in 1909, the US adopts a new cartridge and modified 1903 rifle based on the 30-40 Rimless. It takes advantage of the Spitzer bullet as well as other technological advancements in smokeless powders, case and bullet designs learned from other countries.


a) The new cartridge uses a 150 gr Spitzer bullet with a muzzle velocity of 2600 fps.
b) The cartridge operates at 46,000 pounds, up from of the original cartridge’s 40,000. This matches the pressures of most cartridges of the day.
c) The body taper has been decreased. This provides more powder capacity while at the same time prevents chambering in the old Krag rifles which are still in inventory. The older ammunition can be fired in the improved chamber in an emergency.
d) The 1903 rifle with rod bayonets are to be reworked with the older Krag knife bayonet system, improved chambering and new rear sight to match the new cartridges bullet trajectory.
e) The new cartridge designation is Cal 30 1909 or 30-09.


8- The new rifles work well in the Great War, and the Pattern 14 Enfield rifle production lines adapt quickly to the 30-09 cartridge in the US Model 1917. The only changes needed from the 303 British cartridges are modifications to the cartridge follower, clip slot, extractor, rear sights and of course, the barrel bore diameter. Production changes over ahead of schedule.


9- The 30-09 cartridge remains unchanged until the 1920s when the 173 gr Cupro-Nickel boat tailed bullet is adopted in 1926. It is designated the 30-09 Mk2. Chamber pressures increase to 50,000 and muzzle velocity is 2400 fps. The improvement was heralded as a technological marvel with much greater accuracy, range and less barrel fouling than the previous cartridge. The best part is that it can be fired in all 1903 rifles with only the rear sight ladder replaced for the flatter trajectory.


10- The new cartridge and rifle set new records at the 1926 National Matches in Camp Perry Ohio.


11- The .276 Pederson cartridge and rifle systems are quickly dropped in 1927. Work was to continue on the rifle using the new 30-09 Mk2 round.


12- The M1 Garand rifle is adopted using the 30-09 Mk2 in 1933, 3 years ahead of schedule.


13- The 30-09 Mk2 finally begins phasing out with the introduction of the M14 in 1959. There was quite a controversy whether or not to retain the 30-09 Mk2 cartridge for the new service rifle which delayed adoption for 2 years. Finally, a new cartridge was adopted called the 7mm-08. :)"