BoydAllen
Gold $$ Contributor
I started out with my 6.5 x 47 barrel with a Redding bushing FL die, and unturned necks. The barrel's chamber neck is .294 and after some work with various loads, I finally took a more careful look at what my loaded rounds' neck to chamber neck clearance is, and decided that I would like a bit more clearance. As it turns out, a VERY slight cleanup will give me a neck thickness of .0125 and a loaded round clearance of .004
Because all of my brass had been fired by the time that I had gotten around to deciding this, and a bushing die does not size all the way to the shoulder (in this case stopping about .040 short) I ordered a Forster one piece FL die that would.
When it arrived, the first thing that I did, after setting it for the proper amount of shoulder bump, was to measure what the die without the expander sized case necks down to. That measurement turned out to be .284. With the expander it increased by .005 to .289 (unturned case).
For those that are not familiar with their dies, Apparently Forster has put more thought into their expander setup than their competition. The "ball" (part that does the actual expanding) is tapered on both ends and does not secure the decapping pin. It actually screws down from the top of the rod, and is about .9 higher ( for this caliber) than the usual dual purpose expander/ decapping pin retainer. This really improves case alignment during neck expansion, and because of that improves concentricity over what a more "normal" design would give from a one piece die. As the expanding of the neck begins, the mouth of the case is still in the bottom of the neck part of the die, and the decapping pin is still in the flash hole, both of which contribute to case alignment as the expander starts through the neck.
Curious about what the runout actually was on my first sized case, I pulled out my 20 year (or more) year old Sinclair concentricity gauge (the one with the three square bars on a rod). It was amazing, seriously. The case mouth runout was less than .001, form a one piece die with the expander in place! The ONLY downside to this rig is that it works the necks more than I want, particularly with the price of brass these days. From a strictly loading/shooting perspective it is right on ( at least it seems to be based on a one case sample ;-).
The neck tension works out about right.
The next thing I did was to compare the die's sized case body dimensions to those of the Redding die. The Redding die's dimensions worked fine. I just wanted to know what the difference (if any) is. The sized shoulder diameters are the same, and a bit above the extractor groove (where the sizing marks and chamber engagement ends) the Redding sized case is about .001 larger.
I checked the concentricity of the Redding sized case that I had pulled to check its body dimensions, and was again pleasantly surprised. It was .001 on the case mouth. Nice.
At this point I am going to run the rest of my cases through the Forster die, so that they are sized all the way down to the neck shoulder junction, and ready to be expanded and neck turned. I thought about expanding them, but my experience has been that they contract if you do not turn right after you expand, and the turning mandrel may be a week out. (small order glitch..no big)
Added later: Somehow in the process of taking the decapping stem out and putting it back in a couple of times, I managed to raise the rod in its adapter to the point where the expander got too close to the top of the die. This, combined with an "I'll just put more force on the handle"/ stupidity will quite effectively collapse a case shoulder. ( Ask me how I know this.) So much for having an even number of cases. After I got my decapping assembly set so that the primer comes out at the very end of the press stroke the pin is sticking out of the bottom of the die about .170. (Remind me to write that down somewhere.) Since I had not gotten around to removing the lube from the cases, I decided to carefully run them through the Forster die, with the decapping assembly in place and then measure their runout. When I did, there were a couple of cases that had perhaps .002 to .0025 runout on the end of their case mouths, so with time on my hands, and no way to turn the necks, I reprocessed those two, removing the decapping assembly from the die once more, sizing them, and using the expander die to expand the necks, in three stages, turning the cases a little after the first two. The necks were now all within .001. If television had been more riveting, I would probably not have bothered. In a week or so, the necks will have shrunk a bit, and I will run them over the expander and turn them, to .0125 for a total loaded round clearance of .004. I hope that those of you who occasionally make stupid mistakes while reloading feel better now, knowing that I too am a member of your club.
Because all of my brass had been fired by the time that I had gotten around to deciding this, and a bushing die does not size all the way to the shoulder (in this case stopping about .040 short) I ordered a Forster one piece FL die that would.
When it arrived, the first thing that I did, after setting it for the proper amount of shoulder bump, was to measure what the die without the expander sized case necks down to. That measurement turned out to be .284. With the expander it increased by .005 to .289 (unturned case).
For those that are not familiar with their dies, Apparently Forster has put more thought into their expander setup than their competition. The "ball" (part that does the actual expanding) is tapered on both ends and does not secure the decapping pin. It actually screws down from the top of the rod, and is about .9 higher ( for this caliber) than the usual dual purpose expander/ decapping pin retainer. This really improves case alignment during neck expansion, and because of that improves concentricity over what a more "normal" design would give from a one piece die. As the expanding of the neck begins, the mouth of the case is still in the bottom of the neck part of the die, and the decapping pin is still in the flash hole, both of which contribute to case alignment as the expander starts through the neck.
Curious about what the runout actually was on my first sized case, I pulled out my 20 year (or more) year old Sinclair concentricity gauge (the one with the three square bars on a rod). It was amazing, seriously. The case mouth runout was less than .001, form a one piece die with the expander in place! The ONLY downside to this rig is that it works the necks more than I want, particularly with the price of brass these days. From a strictly loading/shooting perspective it is right on ( at least it seems to be based on a one case sample ;-).
The neck tension works out about right.
The next thing I did was to compare the die's sized case body dimensions to those of the Redding die. The Redding die's dimensions worked fine. I just wanted to know what the difference (if any) is. The sized shoulder diameters are the same, and a bit above the extractor groove (where the sizing marks and chamber engagement ends) the Redding sized case is about .001 larger.
I checked the concentricity of the Redding sized case that I had pulled to check its body dimensions, and was again pleasantly surprised. It was .001 on the case mouth. Nice.
At this point I am going to run the rest of my cases through the Forster die, so that they are sized all the way down to the neck shoulder junction, and ready to be expanded and neck turned. I thought about expanding them, but my experience has been that they contract if you do not turn right after you expand, and the turning mandrel may be a week out. (small order glitch..no big)
Added later: Somehow in the process of taking the decapping stem out and putting it back in a couple of times, I managed to raise the rod in its adapter to the point where the expander got too close to the top of the die. This, combined with an "I'll just put more force on the handle"/ stupidity will quite effectively collapse a case shoulder. ( Ask me how I know this.) So much for having an even number of cases. After I got my decapping assembly set so that the primer comes out at the very end of the press stroke the pin is sticking out of the bottom of the die about .170. (Remind me to write that down somewhere.) Since I had not gotten around to removing the lube from the cases, I decided to carefully run them through the Forster die, with the decapping assembly in place and then measure their runout. When I did, there were a couple of cases that had perhaps .002 to .0025 runout on the end of their case mouths, so with time on my hands, and no way to turn the necks, I reprocessed those two, removing the decapping assembly from the die once more, sizing them, and using the expander die to expand the necks, in three stages, turning the cases a little after the first two. The necks were now all within .001. If television had been more riveting, I would probably not have bothered. In a week or so, the necks will have shrunk a bit, and I will run them over the expander and turn them, to .0125 for a total loaded round clearance of .004. I hope that those of you who occasionally make stupid mistakes while reloading feel better now, knowing that I too am a member of your club.
. From one club member to another...
