303 British Neck Sizing Die for 30/40 Krag

[concretus]

Hello,
I recently purchased an 1898 Springfield. The guy I got it from said after he slugged the barrel, he determined the bore to be at .310. He used 311. bullets to get the best accuracy. I want to reload for the rifle but just want to neck size to get the most out of the brass. Would it be possible to use a neck sizing die for a .303 British caliber to get the proper neck diameter for .311 Bullets? Thanks

Information

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[Parashooter]

.30-40 case is a hair larger at shoulder than .303, so a close-fitting .303 neck die may not clear upper body, resulting in shoulder displacement. 7.65x53 ("Argentine") Mauser die does the job for me, sizing neck to .03" from .30-40 shoulder, which is more than enough, and provides plenty of body clearance.

If you haven't yet purchased dies, I'd suggest a .30-40 FL set and an extra expander made for .311" bullets. .30-40 case geometry permits neck sizing with backed-off FL die. Neck will be worked a bit more than in 7.65 die but regular annealing takes care of any added work-hardening.

[concretus]

Thanks for your input! Would I need to re-size the whole length of the neck? Or just enough to hold the bullet?

[browningautorifle]

Would I need to re-size the whole length of the neck

I'd do the whole neck just short of the shoulder. Remember to use a touch of lube at the case mouth to keep them coming out easy, or it will be very hard on the upstroke of the handle...

[Parashooter]

Would I need to re-size the whole length of the neck? Or just enough to hold the bullet?

It's fairly pointless (but mostly harmless) to size the neck any farther than the depth to which the bullet is seated (not counting any boattail, which doesn't actually contact the case). Some claim the unsized portion of neck helps center the cartridge, though a little solid geometry logic tells us the conical shoulder does that job just fine by itself - assuming the chamber is properly concentric with the bore and the case shoulder cone firmly contacts the chamber cone.

[concretus]

thank you all for the information

[CINDERS]

Partial neck sizing that is not doing the whole neck over a period of loading/sizings can lead to what we effies call "Doughnutting" where the ring left by the partial neck size grows through brass flow to a point where it will not fit into the neck of the chamber the first signs of this will be cases that are hard to chamber.
I take it down all the way as I fls all my cases annealing when required the only 303 I neck size is my T brass as this stays with that particular rifle.
You can set up the FLS die to do just the neck as you are not bumping the shoulder the case is also fire formed to the chamber so your concentrically bullet to bore will be good, the brass will last longer also. Just my take on matters.

[concretus]

Well I have some results with some test loads after I backed backed the FL size die 1 1/4 turns. I took this old gal to the range yesterday. Here are the results: All targets were fired from 50yds. I wanted to see what it would do before I pulled the target back. The first photo is using Sierra 150gr .311 bullets, R-P brass, Win LR primer and 36.0 grains of IMR-4895...It measured just under 1 1/4". I used the peep sight flipped up and six-o-clock hold.
The second photo was using Sierra 147gr .311 MK, R-P brass, Win LR primers and 35.ogr of IMR-4895. It measured about 7/8". I had the flip up sight laying down and was aiming at the lower target w/ a six-o-clock hold. Next week I'll go to 100yds.Thanks again for the advise.

[browningautorifle]

Top one looks good, obviously the bigger diameter bullets are the way to go. Don't know why the second group is so far right though...they group nicely.

[concretus]

Top one looks good, obviously the bigger diameter bullets are the way to go. Don't know why the second group is so far right though...they group nicely.

The group on the bottom; I didn't flip up the sight. I guess the Krag rifle has a 300 yd battlefield zero. I was aiming at the bottom target using a six-o-clock hold. The top photo I flipped up the rear sight and adjusted it using the peep sight. I'll use that from now on for 100yds and out....