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shoulder bump problem

I just picked up my 6.5-284 from my gunsmith this past weekend. He did a bit of load testing with it and I am ready to start fine tuning some loads using once fired cases. He, and others, recommend bumping the shoulder back 0.002-3 when neck sizing. He built the chamber for a tight fit on the Lapua brass and I am measuring about 0.003' difference from unfired to once fired cases when measuring from base to shoulder using a tool he made using the barrel trim piece and the chamber reamer. I have a Redding Type S bushing sizer die that is chamber matched. The problem I have is that I cannot get the shoulder to bump back at all. In fact, I get about 0.001-2 growth when I try to bump. I have tried the standard Redding shell holder and all the different sizes of Redding competition shell holders that incrementally change the amount of headspace. I started with the sizer die 1 full turn from touching the ram at full throw,recommended by Redding) and even tried the sizer die touching the ram at full throw. I have the Redding UltraMag press so I plenty of strength to size the cases. Any ideas as to what is going on here? My gunsmith buddy is a bit perplexed at the moment as well.

Best,
Archerross
 
I have experienced the same problem and the solution is simple. The problem is caused by the chamber in the rifle being cut to a slightly different depth in comparison to the resizing die. If you take your shellholder and remove a small amount of metal from the upper face of it,say .005') that will allow you to lower the resizing die by up to the same amount. Keep doing that until you can bump the shoulder by .001-.002 or whatever your gunsmith recommends. You could have it machined but I did mine on an oilstone using a bit of elbow grease, it wasn't that difficult. Alternatively I understand one of the reloading manufacturers makes undersized shellholders. A word of caution, think carefully if you are tempted to remove metal from the bottom of the die instead of the shellholder as some may advise, shellholders are cheap, sizing dies......
Hope that this helps, Jim.
 
If it were me, I would use a Forester bushing neck/ bump die. If the body of your cases will fit back in your chamber, this will neck size and bump the shoulder back, with out touching the case body.
This is what I use on my 6BR cases. And when the body need sizing, I use a Redding body only sizer die, and just set it to size down the body .001 less that the chamber.
And that same amount .001 on the shoulder bump die, to reduce your cases headspace by .001 shorter than your chamber. Then if a case needs a bump, it gets it automatically, when you neck size. I know there are several ways to do this, and this is just how I do it.
M.
 
the redding neck die will not bump the shoulder back. you will need to use the fl die to move the shoulder.
 
I had the same problem with my 6br. I had a custom reamer made from my loaded rounds. After I got my gun finished and went to resize the fired rounds I noticed that the Forster full length die was not bumping the shoulder back enough. I took a few thousandths of my die and this corrected the problem,make sure you sneek up on it though as you dont want to take to much).I asked the same question and someone told me to chuck my shellholder in a drill press and run it down on a stone to remove a few thousands. This would have been better than taking of the die as was mentioned earlier.
 
Well, I double checked the die I am using and it is the Type S Bushing Full Sizing die,6.5-284 B/FL). It sounds to me that I am in the same predicament as 243jimb and jec... correct die to bump the shoulder, but not enough throw to get it done. I suppose I'll need to consider grinding a few thous off the shell holder since as 243jimb so eloquently stated
shellholders are cheap, sizing dies......
Thanks for the info guys. I'm just getting into the precision game and I have much to learn.

Ross
 
As much as a hate to say this, but your chamber must be to short, do you have access to go-no go gauges for this caliber? And yes you can correct for it by removing some off the shell holder, and use your FL sizing die, but mark the shell holder as special for this chamber.
And if you need to bump the shoulder back after every firing, and you dont have a shoulder bump die, you wont be able to shoot fire formed brass.
M.
 
I do not have a go-no go gauge for this caliber. I would assume that the experienced gunsmith who built it would have done so properly. Maybe I assume too much. I decided I wanted to use Lapua brass, so he built the chamber to fit Lapua. He is going to trim up the die so that I will be able to adjust the bump in 0.002 increments using the Redding Comp. shell holders.
 
That will work, and with the die matched to the chamber,,I missed that part in my first read) you wont be FL sizing, unless it needs a little slimming, and you will have a nice tight cases to chamber fit. This is the premium way to go with your die. So It sound like your all set.
Good Luck and fave fun. M.
 

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