Concerns about neck reaming .444

[S.R.Custom]

Long story short: Am experimenting with 405 gr bullets in the .444 marlin, but to seat a bullet that long in a .444 case and have it fit the chamber, I find myself having to inside-ream the case necks. Conceptually, this is not a problem, but...

I got my .429 Forster neck reamer in the mail, and it does exactly what I want it to do, but it leaves a rather sharp step inside the case where the reamer stops. Hrmmmm.... (I'm concerned about case separation here.)

Making sure of proper annealment is obviously on the checklist, but should I also alter the reamer so that it leaves a more gradual transition to full brass thickness, or am I worrying needlessly?

[leftiye]

Modifying the reamer to a long taper is the top drawer way to go, but I don't think case separations are in the cards if you don't. Unless you have plans for a heavier boolit, the shoulder shouldn't affect anything.

[porkchop bob]

Good morning. I think a step inside the case is a plus. The boolit can not be seated past it. That eliminates another variable in the mix.
Bob

[Char-Gar]

My thoughts on the matter...

1) Outside neck turning is a better way than reaming to reduce the thickness of the case neck. It is produces a more concentric neck with uniform wall thickness.

2) If you ream, the step is not a bad thing. If provides a stop for the bullet as it is seated.

3) You fears of case failure due to reaming are not real world based.

[1Shirt]

Will be very interested in your results with the process, as well as your load(s).
Please be sure to follow up on this thread as you work through the loading and shooting of the heavy one.
1Shirt!

[S.R.Custom]

Will do...

The whole purpose of the exercise is to see if I can come up with 45-70 performance in a compact, trail-pack friendly package...

Preliminary mock-ups indicate I was spot-on with my Mountain Mould design-- loaded into a SAAMI-spec length case, the 405 grainer yields a SAAMI-spec length cartridge that oh-so-gently kisses the rifling. Chambering is tight, tho, hence the reaming.

The biggest PITA with this project has been the fact that the Winchester won't feed a SAAMI length .444 cartridge. I had to machine an "inverted" feed ramp into the top of the magazine/receiver hole to provide enough clearance for the cartridge to tip up on the elevator. (I was NOT going to compromise that exquisite fit to the throat by trimming the case.)

Initial analysis and theorizing indicates the powder charge will be a purt-near 100% loading of either 2230 or H335. I'm hoping for 1800 fps. Testing won't be 'til warm weather, as this shoulder will have to be most thoroughly rehabilitated before I subject it to this, lol...

Input regarding the step resulting from the reaming is noted. The perfectionist in me will no doubt try to place said step in the case so as to provide a positive stop for bullet seating... Will make a small, initial run of cases so as to test for case life. I'll be watching for the tell-tale bright ring...

[9.3X62AL]

Will the twist rate in the Winchester support a boolit of that length? Marlin uses 1:38", which prompts a question in my mind. Long live Greenhill. I see no other reason that the 444 shouldn't be a better rival and possible equal of the 45-70, other than the short-sighted twist rate it has been crippled with since its birthing.

[Scrounger]

Will the twist rate in the Winchester support a boolit of that length? Marlin uses 1:38", which prompts a question in my mind. Long live Greenhill. I see no other reason that the 444 shouldn't be a better rival and possible equal of the 45-70, other than the short-sighted twist rate it has been crippled with since its birthing.

Marlin .444s made in the last 6 or 7 years have a 1 in 20 twist. I have one I'm trying to sell.