Cast Bullet Experiments with the .256 Newton


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Cast Bullet Experiments with the .256 Newton

Charles Newton was an inventor back in the early 1900s. He is mainly remembered for the cartridges he designed, like the .22 Savage Hi-Power, the .250/3000 Savage, and his proprietary line of cartridges, the best known of which is probably the .30 Newton (a belt-less magnum), but he also designed and built his own line of rifles (both standard length and magnum length actions). These rifles had some interesting features – 6 locking lugs on the bolt for added strength, set triggers, the action screw being integrated into the action floorplate to insure that the action was always torqued into the stock the same amount each time it was assembled, a steel insert in the tang to help prevent the pistol grip from splitting, and a safety that rotated 360 degrees that could lock the bolt, or not, depending on what the shooter wanted.

256 Newton bolt.jpg

256 Newton action.jpg

256 Newton floorplate.jpg
Pictures of rifle features

Newton was a very bright firearms man, but had trouble running a business, and went bankrupt more than once. The very first Newton rifles (a couple dozen) were made by Mauser and imported by Newton Arms Co. (founded in 1914). This supply dried up with the start of World War I, forcing Newton to make his own rifles. The First Model 1916 rifles were made in Buffalo, NY with Newton overseeing production. This lasted for 16 months, during which time about 2400 rifles were made. The company went into receivership, and the assets sold to Newton Arms Corporation (New York City), who were also in business for about 16 months, during which time they sold about 1600 rifles. So the total number of Model 1916s made was about 4000 rifles.

In 1919, Newton started the Chas. Newton Rifle Co., and once again was importing rifles from Germany (this time about 100 guns from Sauer-Mauser). These guns are known as Model 1922 Newtons. This effort did not last, and once again, the business went belly-up and the assets were sold off.

In 1923, the Buffalo Newton Rifle Co. was started. As I understand it, Newton was involved with this effort, but was not the owner and not in charge. A newly designed rifle was produced in New Haven, Connecticut that became known as the Second Model 1924 Buffalo Newton. Only about 1000 of the Buffalo Newtons were made.

One of the other cartridges that Charles Newton designed in 1913 was the .256 Newton (named for the nominal bore diameter, not the bullet diameter). This cartridge is based on the .30-06 case, necked down to 6.5mm, with the shoulder pushed back slightly and sharpened to 23 degrees, and the case trimmed to a length of 2.440”. Newton viewed this cartridge as a high velocity hunting round, shooting 120-140 grain bullets at or above 3000 fps (i.e. a .270 Win over 10 years before Winchester introduced the .270 Winchester). To attain these velocities, Newton focused on bullet weights in the 120-140 grain range, and used a 1 in 10” twist (the 1 in 8” twist common in other 6.5mm rifles was chosen to stabilize the longer 160 grain RN bullets).

256 Newton case forming.jpg
.256 Newton case forming steps (l-r: .30-06 case, necked down, trimmed to length, neck turned).

I’m a big fan of 6.5mm cartridges, and the .256 Newton has long intrigued me. A number of years ago, I got the opportunity to trade into a .256 Newton. The serial number (10xx) places it as a First Model 1916, made in Buffalo.

It came with dies, and case forming was pretty straightforward. I used military .30-06 brass, and as long as I annealed the neck/shoulder region of the cases, I had no problems and lost no cases (unannealed brass did not fare so well). Run them through the sizer die, trim to length, and load them up.

Preliminary tests with 6.5mm jacketed bullets (which tend to run .263-.264” in diameter) were disappointing. It is worth noting that for these jacketed bullet loads, all ammo chambered effortlessly (no neck turning required).

Preliminary tests with the Lyman 266469, sized .264” were likewise disappointing. Attempts to size the Loverin bullet .266” started to reveal problems – sometime the ammo would chamber, sometimes it would not. This led me to collect a few measurements.

.256 Newtons have a reputation for having oversized throat and bores, and this rifle is no exception. As near as I can measure it, this rifle has a throat of .267+”, a groove diameter of .267”, and a bore diameter of .263”. The neck diameter of the chamber is about .294”.

The military .30-06 brass I was using to form cases had a neck wall thickness of about .015”, so with a bullet diameter of .263” and 2 necks walls of .015”, the total comes to .293”, which chambered readily. With a bullet diameter of .266” and 2 necks walls of .015”, the total comes to .296”, which is no-go (those individual rounds that did chamber must have had slightly thinner neck walls). So I took a handful of cases and turned the necks to .012”, and voila! Rounds loaded with the 266469 sized .266” chambered just fine now, but still shot poorly (although better than before). .266” + .012” + .012” = .290”

So I had my friend Erik Ohlen hone out a sizer die for me to .268”, and had Dan Lynch of Mountain Molds make me a .268” diameter 140 grain GC-FP that I patterned after the RCBS 30-180-FN. Finally! I started to see groups! 22.0-25.0 grains of 4895 shot well with this bullet sized .268” in the neck-turned cases. These loads should be running about 1600-1800 fps. When I took the load up to 26.6 grains of 4895, the ammo became wildly inaccurate (this load should be doing 1900+ fps). I can get this bullet to shoot well at this speed in my Remington 700 6.5x55, which has a 1 in 9” twist, but that is a much tighter gun, and the bore is in factory new condition, this Newton is over 100 years old and the bore is showing some wear.

256 Newton and MM 268 140 GC.jpg
.256 Newton loaded with MM 140 grain GC-FP.

256 Newton with NOE 270469.jpg
.256 Newton loaded with NOE 270469.

The oversized Loverin NOE 270469 also sized down to .268” nicely and shot well over 16.0 grains of 4227 (1600 fps).

I tried sizing these bullets .270” and ran into more chambering problems using the neck-turned cases. I may turn some necks to .010” and try .270” cast bullets in the .256 Newton. But then again, I may just settle on .268” cast bullets with 23.0 grains of 4895 (1700 fps) or 16.0 grains of 4227 (1600 fps) and call it good enough for a 100+ year old rifle.