Bonanza Sizing Die

P

Picher

New member
I was trying to size some .270 Win cases with my Bonanza Sizing die the other day and it crunched the shoulder on the first case. (For those unfamiliar with the excellent Bonanza dies, the expander is located higher on the decapping rod, where press stroke is near it's maximum force. Expanding is smooth and chatter-free.)

Thinking I may have misaligned something, tried another and the same thing happened. I unscrewed the decapping stem and everything looked okay, but the expander button had unscrewed a bit. For those who aren't familiar with these dies, the expander button is mounted on the decapping rod much higher than on most dies, where it's located at the bottom of the decapping rod and used to hold the decapping pin in place.

There is little room for error in setting the expander button on the shaft. It must be located below the neck resizing portion of the die sufficiently to keep from pinching it between the resizing and expanding functions.

The cure was to clean off the expander portion of the decapping rod and use Loctite to hold the expander in place at the bottom of those threads. Next, set the rod in the proper location so the decapper pin retainer clears the inside of the case web, but not high enough for the expander to interfere with resizing the neck portion of cases.

It probably took me longer than it should have to discover the cure, so I'm passing the info to you folks, since it's kind of difficult to determine what's going on.
 
Same thing only different, I was sizing/going through 100 257 Weatherby cases when I collapsed the shoulder of a case 'Actually:D' the case body collapsed below the shoulder/case body juncture. I removed the case and checked the case head, it was a 300 weatherby mag. case.

And then I though about all the times I have heard someone say 'all you gotta do is run the case through the full length sizing die to form cases, you don't need no forming die'.

And then things came to a sudden stop. I am loading 150 30/06 cases, all with R-P head stamps. Problem, I was a few short so I dug out a few. When I started sizing the few the press locked up, no clue, 1 box/ 20 of the 30/06 cases had been necked down to 270. The out outside diameter of the necks were larger than a 270 case, they were slightly shorter. I do not need 270 cases bad enough to form from 30/06 cases. I can only guess someone wanted to tighten the necks in a 270 chamber.

Pacific dies, I have a few that go back to the 50s, I also have a few RCBS dies from the same period, it would appear both dies were made by the same manufacturer.

F. Guffey
 
I have 8 Bonanza sizers and 15 Forster sizers [same thing]
None of them have the expander ball, decapping stem installed.
8 of my Forster sizers have been honed out to my specs on Forsters Hardinge collet lathes. The expander ball would probably cause no harm with those.
I am still putting the stem back in.

I decap with a Lee decapping die or a Lee collet neck die.
I may use an M die or make a mandrel die on the push stroke, but no way am I ever going to use an expander ball on the pull stroke.

Pulling with an expander ball:
1) I would have to lube the inside of the neck.
2) The neck would be invisibly, but measurably bent, spoiling group size.
 
I haven't noticed any accuracy problems when the Bonanza expander ball is used on the downstroke in the sizing operation. I am not a CF competition shooter, but have fired groups of .4" and smaller at 100 yards with both .270 Win rifles, using the regular sizing process...without lubing the insides of case necks, though inside necks are usually cleaned with 000 steel wool on a rotating brush, especially if the rounds are to be stored for several months.

All of my other CF rounds are sized by the standard process, though mostly using RCBS dies. The .223 Rem and .243 Win rifles routinely shoot 1/4" - 3/8" groups and smaller at 100 yards when using the process.

I'm not saying it doesn't make a difference, just that I'm satisfied that the process I use meets my relatively-demanding desires.
 
Picher the shoulder could collapse if you had the expander ball too high in the sizing die. Lower the expander ball a little bit and this problem should be solved.
 
I have shortened the sizer ball distance from the top of the die, for no other reason than get the clunk closer to the top of the down stroke.

F. Guffey
 
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