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Discussion Starter · #1 ·
Hello to all, I am new to the board here and was wondering if someone could share some info on head space. When only neck sizing does the head space change, can you adjust the neck die to bump the shoulder, or does the FL die need to be used to bump the shoulder. If a cartridge that is fired expands to fill the chamber and then contracts back to near the original dimensions before being fired. How would I know how much to bump the shoulder to get that 0.001 to 0.002 of clearance between the case and chamber shoulders.

I have checked the dimensions of my chamber at the saami website and there they give you the minimum and maximum dim. But how do I determine the dimensions of my chamber so I know how much to bump or not. I am waiting on a headspace gauge to arrive to help me determine where I am at now regarding head space measurement. If anyone would care to share their methods I would really appreciate any and all input. You can pm me if you don't want to publish you method on here.

Thank you very much
Dan
 

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First I have not loaded in years. Second I always used full resize dies. This eliminates a lot of problems. The more you work the shoulders the quicker the shells will crack (when over forming). For hunting full length is the way to go. If shooting paper is your game then, you can continue the persuit. I could never find a good recipe for paper though.
 

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Discussion Starter · #3 ·
well i guess you can say i punch alot of paper in pursuit of the perfect hunting bullet/powder/length combination. i have had some good success in the past, but i am always looking to improve just that litte bit more. i have convinced myself that i am only going to test one more different type of powder for hunting cartrdges. then try some match grade bullets for target shooting. i have a remington model 700 w/1" barrel chambered for a 6mm cartridge. i just mounted a leupold vx3 4.5x14 w/ varm reticle on it. i made up 7 different loads to test this weekend then decide what i am going to stick with. the rifle has a few years on it but is still capable of achieving some pretty small groups. getting back to head space since it is something i have really looked at as with my 6mm i only neck size,trim and never have a problem with a hard closing issue's. as well i get very few neck splits after multiple firings. my rem. sendero 7mm ultra mag is a different story, i have to full size quite often. i guess i will just use the saami spec as a guideline, and when i get my head space gauge, i will be better to understand what my rifles likes. thanks for the response.

everyday is a good day to shoot!
 

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In the past I have reloaded for four different calibers. Using different cases, powders, grains of powder, bullet types, bullet weights, primers, bullets seated to different depths. Enough to drive you mad. Sometimes after a day shooting it seems like you are no further ahead than when you started. So it is trying to acheive the perfect load. If you have the patience then go for it. This is a whole different animal though. Remember though that a shell that is snug in your basement can jam your gun with just a little dirt in the field. That extra inch you gain at 400 or 500 could cost you a large animal at 50.
 

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Welcome to the board Dan. :welcome: I am not sure I understand your question or concern. You don't need to bump the shoulder until you have bolt closing issues. That could easily be on the fifth reloading depending on the brass and how hot the loads are. Neck sizing will not bump the shoulder. The full length die will. If you are asking how much to bump the shoulder when you need to, it's really easy. You could do a complete full length sizing and start the sequence over or try bumping a little at a time until the bolt closing issues dissappear and go from there. Probably just as simple to full length size completely at that point. I have tried to bump just a little but pretty much wound up with a complete FL setting before the cases would chamber. There are two dimensions at play there as well, head space and case width. The last part of the press stroke bumps the shoulder as well as narrows the case near the web. Either or both of those could be contributing to eventual bolt closing issues. Many benchrest and long distance shooters do not neck size, they FL size. But then they have tight chambers and great barrels too.
As for using only full length sized brass to create hunting loads; what I have done is to test chamber all empty neck sized brass first and cull any on the edge. Load them and you should be fine. I usually use a Lee crimp die on those cartridges too just to be sure there will be no loose projectile issues too. If you have concerns about chambering neck sized loads in the field and the gun is mainly to be used for hunting then I would just full length size. If you can work up a load from FL brass that groups an inch or under it will serve you as well as any factory round out to 300 yds or so. At that range your heartbeat will make you more innaccurate than the rifle anyway. One other point in all this is to use a batch or multiple batches of brass without mixing headstamps within a batch. This will save you grief. Consistency in all things develops accuracy; brass, charge weights, seating depths, crimping (some say), barrel cleaning, etc.
May I ask how you test loads?
 

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Discussion Starter · #6 ·
hello again, thanks for the replies and the welcome note. sorry i am not trying to be rude here by ignoring your replies. but i type out a big long reply on my blackberry, and that reply is somewhere in cyber space. so i started another reply ran out of time so i saved the draft and now i don't know how to find it. any suggestions
 

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I would bet its not a mechanical headspace issue, but as mentioned, perhaps something is out of whack in the process of re-sizing your cases. Again, as mentioned, F/L resize properly and I would bet those issue will disappear.
 

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Oh and another thought there Ice man. Over the last number of days I was mulling over why I am not head over heels in love with the paper shooting game. Then it came to me. Many years ago I lost one of my hunting partners to the paper shooting game. He tried it, got involved in competitions and coaching and he has been LOST ever since. I did not even realize that I still have left over feelings of betrayal. Now I do not think he hunts or cooks paper. What a terrible thing. :lol:
 

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Don't know what to tell you about the Blackberry other than use a computer to reply. Are you posting within the forum as a reply?
Is your issue not being able to chamber brass that has been neck sized only and trimmed in that particular rifle?
 

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icemandan said:
Hello to all, I am new to the board here and was wondering if someone could share some info on head space. When only neck sizing does the head space change, can you adjust the neck die to bump the shoulder, or does the FL die need to be used to bump the shoulder. If a cartridge that is fired expands to fill the chamber and then contracts back to near the original dimensions before being fired. How would I know how much to bump the shoulder to get that 0.001 to 0.002 of clearance between the case and chamber shoulders.

I have checked the dimensions of my chamber at the saami website and there they give you the minimum and maximum dim. But how do I determine the dimensions of my chamber so I know how much to bump or not. I am waiting on a headspace gauge to arrive to help me determine where I am at now regarding head space measurement. If anyone would care to share their methods I would really appreciate any and all input. You can pm me if you don't want to publish you method on here.

Thank you very much
Dan
Dan Headspace is the space between the boltface and the head of the case when the cartridge is as far forward in the chamber as it can go. After the cartridge has been fired in your chamber it should have zero headspace. When the cartridge is fired it expands to the exact diminsions of your chamber and if you do not exceed the elastic limit of that brass (caused by excessive pressure) the brass will relax approx .0005". If a high pressure load exceeds the elastic limit of the brass the case will remain the exact dimension of the chamber and will be difficult to remove.
I don't quite understand what your problem is but I believe you are having difficulty chambering the case in your rifle after you have resized the case. Assuming your chamber is round and you are not loading to extremely high pressures that exceed the elastic limit of your cases you should not have any great problem chambering a fired case. Try chambering one. As already mentioned there are many die makers and press makers and they have different instructions on how to set them up. I would suggest you try the following. Set the decap pin so it protrudes approx 1/4 inch out the bottom of your die. Ensure the pin is centred in the die body. Screw the resize die into your press until there is a 1/4 inch gap between the bottom of the die and the shellholder when the ram is in the full uppermost position. Lube a fired case and size it. The spent primer may not be removed,ensure it is not partially protruding from the case head. Try to chamber this round. It should chamber freely or with slight resistance.You will likely notice the neck has been sized partway down the neck. Turn the die down one more turn in the press. Resize the case and observe that the primer is not protuding or has been removed and how far down the neck has been sized.Again try chambering the round.
Continue to turn down the die 1 turn or even 1/2 turn at a time until the neck is resized right down to the shoulder..Make very small adjustments to your die as you get close to completely sizing the neck. You should get to a point where any resistance to chambering the round in your rifle disappears. Set your lock ring at this position. It doesn't matter if you are hunting or target shooting you do not want to push the shoulder back any further. That will just create headspace and will lead to case head separation.
 
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