Dumb Question - Ackley Improved Dies

[Ben Lamb]

I’m guessing that Ben Lamb is using a universal neck sizer and seater. I guess that works. He MAY be leaving some accuracy on the table since both can contribute to excess runout of the loaded ammo. I would also think that closing the bolt would get a little tough after a few reloads if he isn’t able to size the body and bump the shoulder. IF the neck sizer doesn’t cause any excess runout, then his ammo will certainly fit his chamber well. Neck sizing can make it tough to close a bolt, but done right, it makes the brass last a long time and it takes a good match of your chamber and sizing dies to get the same accuracy while sizing the whole case.

1.) Yes, it's the Hornady 7mm neck sizer. Not specific to the AI or 7mm mauser case.

2.) Most assuredly i leave accuracy on the table, or anywhere else I spill it.

3.) 3 loadings on the Norma brass with no drop in accuracy yet. Somewhere around .75 MOA or a tad under.

4.) No need to trim yet. Everything is still as it should be & no excessive difficulty in closing the bolt on a loaded round.

But now I think I may pick up a 7mm Mauser AI FL Sizer just to be on the safe side.

 

[ImBillT]

1.) Yes, it's the Hornady 7mm neck sizer. Not specific to the AI or 7mm mauser case.

2.) Most assuredly i leave accuracy on the table, or anywhere else I spill it.

3.) 3 loadings on the Norma brass with no drop in accuracy yet. Somewhere around .75 MOA or a tad under.

4.) No need to trim yet. Everything is still as it should be & no excessive difficulty in closing the bolt on a loaded round.

But now I think I may pick up a 7mm Mauser AI FL Sizer just to be on the safe side.

You shouldn’t lose any accuracy just from neck sizing regardless of how many times you do it. You can get to a point where it’s hard to open and close a bolt. How much pressure you subject your cases to has a lot to do with how many reloads you can get before that happens. Where you MIGHT be leaving accuracy on the table wouldn’t be from neck sizing, it would be from using a universal neck sizer instead of one that gets better alignment on the case. That said, since the rest of your case body would tightly fit your chamber, it’s probably not huge.

I neck sized a set of 308Win cases over thirty times with no particular issue when I shot HBR. Yes it was a little hard to open and close the bolt, but nothing troublesome. In my F-class rig I was running considerably higher pressure and the bolt would become intolerable after just two or three reloads. After pulling a bolt handle off in the middle of the match, I switched to sizing the body on every reload.

 

[Mtnhunter1]

140 grain TTSX at 3050 says otherwise.

View attachment 182473

RL-17??

 

[VikingsGuy]

with a soothing British narrator:

David Attenborough he is not . . .

 

[Ben Lamb]

RL-17??

Yep.

 

[jryoung]

I think @jryoung has the formula for cream of wheat as a fire-forming media, as opposed to using mid-range loads. Key for fire forming is getting enough pressure to form the case correctly. W/ a pill, that's a mid-range load. Not sure about the COW way. Could be a less expensive, and shoulder pounding, way to get fire-formed cases.

I ran titewad and for the life of me can't find the recipe. It worked pretty well on my mashburn, but there was a bulge at the base of the neck, but that cleaned up on first firing.

 

[brockel]

I ran titewad and for the life of me can't find the recipe. It worked pretty well on my mashburn, but there was a bulge at the base of the neck, but that cleaned up on first firing.

13 grains of bullseye with cream of wheat worked in my Mashburn

 

[jryoung]

13 grains of bullseye with cream of wheat worked in my Mashburn

Thanks, all my brass from my initial round has a bulge above the belt and I can't seem to fix it. I scored some ADG brass and need to get back to work.

 

[brockel]

Thanks, all my brass from my initial round has a bulge above the belt and I can't seem to fix it. I scored some ADG brass and need to get back to work.

ADG is awesome stuff