FL Resizing issue - 6mm REM
I few years ago I bought a used Remington 600 in 6mm REM. I bought some new brass, neck sized them, and loaded up some Hornady 100gr Interlocks. I also took some Remington Factory 100gr PSP. I found the factory ammo performed pretty decent so I have been using it. Now my oldest son is ready to start shooting more than a 22LR. I full length resized the once-fired brass with the intention of loading up some Sierra 75gr HP with a light load of IMR 4064 for practice for my son. Once I had 50 or so resized brass and tumbled them I tried one in the rifle. The bolt would not close. I tried several more and the bolt would not close on any of them. I reread the directions for setting up a FL sizing die, double and then triple checked that I did not use the neck sizer. It was the FL size die - right caliber too. I also can see that the shoulder is the bearing surface by the fact that there are scratches on it. Factory ammo still works fine. I ended up using the remianing new brass to build the light loads so we could still have fun at the range. I have been reloading exclusively for my 338WM, 280, 7mm-08 and 243 for more than 10 years and I haven't run into this before.
Is this a headspace or a die problem? The dies are a Lyman FL die set that I bought new and an RCBS neck sizer.
I also have to put in an atta boy about my son. (1) He shot well and (2) some idiot at the far end of the range started to walk down to his target while the rest of us were still shooting. He yelled "stop, don't shoot" as loud as he could and made the fool stop in his tracks and turn around. He is 9 and he knows better than an adult. That earned him a milkshake on the way home!
Is this a headspace or a die problem? The dies are a Lyman FL die set that I bought new and an RCBS neck sizer.
I also have to put in an atta boy about my son. (1) He shot well and (2) some idiot at the far end of the range started to walk down to his target while the rest of us were still shooting. He yelled "stop, don't shoot" as loud as he could and made the fool stop in his tracks and turn around. He is 9 and he knows better than an adult. That earned him a milkshake on the way home!
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Hello you may have a defective die in your lyman set or you might have a mis match between the shell holder and the die. Most instruction say to turn the die down until the shell holder bumps the end of the die. If the lyman fl die has a different lenght between the end of die and the shoulder then your rcbs neck die and if you use a rcbs shell holder it might not work unless you stone some off the lenght of the lyman die. If factory ammo is ok then the trouble is with the layman die or shell holder,Cheers Karl 0 -
I also had a problem with an older set of lyman dies (.22/250 cal.) factory ammo=ok, once fired brass=ok, f.l. sized brass=no-go???. changed dies=end of problem. 0 -
Without making any other changes, remove the decapping/expanding stem and FL size a case. Check it.
Expander balls have been known to drag the shoulder forward, and die's have been known to put a slight buldge at the shoulder/body junction when not adjusted properly.
Some guys like a mag full of lead, I still prefer one round to the head.0 -
Ive cured this problem on several occasions by simply holding the top surface of the shellholder against a belt sander and removing a few thousandths. Mike the overall thickness before you start and just touch it to the sander and mike again until its 6- 8 thousandths thinner .This forces the brass that much deeper into the die and makes it work.
I havent had any problems from doing this but it does mess up the shellholder for other calibers.
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mic a fired case at the shoulder/body junction and a sized case at the shoulder/body junction. if the sized case is larger in this area, you have bulged the body by turning the die down too far. back it off 1/4-1/2 turn until they measure the same. Been there, done that, threw away the brass to prove it[;)] The case impacts the shoulder of the die body, and with the remaining stroke left on the ram, it actually pushed too much of the shoulder rearward and the case has to "grow" or bulge to displace the extra material. This is not a bad thing, just something you need to be aware of when setting up the dies. Back them off a hair and see if the problem corrects itself.
why chase the game when the bullet can get em from here?....
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Thanks for the suggestions. I mic'd the shoulder/body junction and it was spot on for both (.431). While I had the mic out, I started to measure everything I could to match it up against the book. All measurements were within spec except one. It is the one from the base of the cartridge to the shoulder/neck junction. The once fired round is 1.882 (just like the book says) and the FL sized brass is 1.893 - .011 difference. Something is stretching the case. On Tailgunners suggestion, I removed the decapping/expander pin and ran a case through the die. Same problem. I cleaned the die too. The other thing I notice is the case length is 2.223 before sizing and 2.235 after - requiring trimming. I am going to stop by the local gunshop on the way home and get a Lyman shellholder and maybe a new set of dies to see if that solves the problem. If not I can keep neck sizing for now and keep my brass separated. I have 2 6mms and that is why I need to FL size.
Thanks for all the help.
Ron0 -
The only thing I can think of at this point is are the dies/cases lubed properly? Did the case drag on the way out when you removed the decapping pin? I should actually say there is one other thing I can think of that would make these cases stretch and that would be of the mouth of the die was too small. It would undersize down around the lower body of the case. In order for that to happen though, and get the case to stretch, the die would have to be a little too high.
We have the second amendment so that all the rest are secure....UNK>0 -
I have yet to see a die pull the shoulder foreward some .011" that is a ton[:0] I would bet there is several .001" error due to not using a bushing to sit on the datum line, but that is still an excessive amount.
1. does the die body touch to shellholder when the ram is fully extended on the press?? if not, turn the die down until it touches and see if that does it. If it IS touching, back it off quite a bit and work your way back down little by little until the measurement from case-head to neck/shoulder junction remains the same.
reason I say this is because there is a method a lot of us use called "partial full length" sizing. The die is started down toward the shellholder but left about the thickness of a nickel away. It is advanced down only until the datum line of the shoulder shows it has been drug forward by about .002". This happens because the die is not all the way down on the case body at the base, so the compression will allow the case to grow foreward in the chamber since the case shoulder and die body shoulder are NOT touching at this point. This resizes enough of the body to aid in feeding, and the shoulder being pulled foreward .002" allows a good compressed fit in the chamber when the bolt is closed. Your die could either be too far down which compresses the case so much over it's entire length that it grows foreward in length, but if your shoulders are that far foreward, I would have to say your die body internal dimension is either VERY generous, or your die is not turned down far enough. If it is making contact, then have a machine shop mill about .010" off of the bottom of the die body and retry that, as the body dimension when turned down to touch the shellholder will be .010" less, and that will make up the shoulder diference you are seeing.
why chase the game when the bullet can get em from here?....
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