30/40 Krag to 303 British

[303carbine]

I had a No1Mk111 that was "generous" in headspace, I had heard of 30/40 through a 303 Brit and wanted to see if I could do it. I pulled the Krag bullets and ran the brass through my 303 fl die. The Krag necks were a bit longer so I trimmed them and reloaded them with a full charge of 4895 under a 180 grain Hornady RN bullet and went to the range.
Accuracy was very good and the brass formed perfectly to the Enfield chamber, the Krag brass fit tighter and lasted longer than 303 Brit brass in my rifle.
Some of the old time shooters I shot with said that the reason Krag brass lasted longer was because it's thicker near the base where 303 brass tends to seperate.
I got 5 reloads out of Krag brass, but only 3 with the same load in Brit brass, perhaps the old dudes knew something......

[Der Gebirgsjager]

Yeah--that's the nature of the beast (No.I Mk.III). So many with excessive to very excessive head space. Can sometimes be corrected by swapping bolt bodies and bolt heads around, but unless you get very lucky you need either unissued parts (hard to find now days) or a pile of used ones to go through and find the right combination. Otherwise some barrel work is needed, and cost can be prohibitive. About the only other remedy, which you've probably been made aware of, is to neck size only your once fired brass. Once that first firing happens you get the incipient case head separation ring just forward of the rim and the damage has essentially been done. But neck sizing only will prevent it from stretching farther on subsequent firings and extend the life of the brass about as long as is possible under the circumstances. Krag brass may help, but as it's "seasonal production" for the big two manufacturers it's kind of hard to replace. Just a SMLE fact of life.

[EDG]

Older Krag brass was about .455 diameter at the head and was a better fit than US made .303.

Most American made .303 brass is .451 to .452
I have had other handloaders tell me their recently made Krag brass is also .451 to .452 like the .303.

Currently manufactured PPU .303 brass measures .454 to .455 at the head so it is probably the best deal going. You get the correct headstamp, a larger head diameter and it is somewhat available. The shoulder of the PPU is also further forward for what ever that is worth.

[Von Gruff]

If you want the best cae fit with the 30-40 case then debullet it as you have done a gradually reduce the length of one case till it fits your chamber as in you find the max length for YOUR chamber then expand the case and start sizing it down (without the expander plug in the die) so you then find where the shoulder of the chamber is so the case is not stretched at the first firing. Having done this you can treat all you cases to the same measurements and with neck sizing only after that you will get a heck of a lot more than 5 reloads in you brass. I have got many times that without any sign of case loss in a couple of Lee Enfield 303's and a Martini as well. Of course zi keep the brass separate and had buckshot make me a larger dia stem for the Lee Collet die and by setting it up to leave a .05 unsized portion of the neck I have fireformed brass (including the shoulder neck junction) for use time after time after time---------------

[W.R.Buchanan]

Currently manufactured PPU .303 brass measures .454 to .455 at the head so it is probably the best deal going. You get the correct headstamp, a larger head diameter and it is somewhat available. The shoulder of the PPU is also further forward for what ever that is worth.

ditto: Try SGA Ammo,,,http://www.sgammo.com/ they sell PPU ammo at very reasonable prices. The brass is definitely the best out there, and after you've shot the factory loaded ammo it is nicely fire formed to your chamber. Then you neck size it only,,, and I would recommend using a Lee Collet Neck Sizing Die as they work the brass the least amount of all.

Just processing the cases in this manner will get you many more loadings with any brand of brass. I am on reload #5 for Cast Boolits using the original WW and RP once fired cases I was given when I started shooting these guns a year ago. WW and RP cases are among the weakest out there, and yet because I am not encouraging case stretching by FL sizing they are lasting well past any expectations.

Randy

[curator]

The real advantage of fie-forming .30-40 Krag brass to .303 British lies in the longer krag case can be trimmed to match your chamber length. Cast boolits really appreciate having the case end at the chamber end, not a huge gap where it will expand and then get swaged down again.

[303carbine]

Curator, you are exactly right about the fit of the brass. After I fireform the first time, I anneal the brass and fire it another three times and repeat the annealing process.
I used the same process to make 8x57 brass from 30-06.

[GOPHER SLAYER]

Good grief, no wonder 30-40 brass is so hard to find.