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Posted: 8/6/2016 6:36:21 PM EDT
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Hy friends
Is there a picture or a draw that explains with no words the head space? |
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Thank you for the scheme.
Now. Headspace is somehow the size of the cartridge segment that corresponds to the headspace. Means too much headspace is a larger cartridge segment? And too less headspace is a smaller cartrige segment, with a space between bolt face and cartridge? Please help me understand this that seems to be extreme important not only for reloadins as also to pick the proper ammo. Thanks |
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I am sure someone can do a better job than I can,,, but look at the bottom pic where it says datum line. To much headspace mean there is to much space between that part of the casing and the end of the chamber where the shoulder would stop. This can lead to case separation and splits.
To little headspace can cause firing out of battery, bolt not fully closing and possible ruptures. This will probably be noticed by a ring around the head of the casing where it expanded. |
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Quoted:
Thank you for the scheme. Now. Headspace is somehow the size of the cartridge segment that corresponds to the headspace. Means too much headspace is a larger cartridge segment? And too less headspace is a smaller cartrige segment, with a space between bolt face and cartridge? Please help me understand this that seems to be extreme important not only for reloadins as also to pick the proper ammo. Thanks There are actually two head-space dimensions; one for the cartridge and one for the chamber. The difference in the dimensions of the actual head-space of a particular chamber and the actual head-space of a particular cartridge is what people are usually referring to when talking of head-space. Think of it as the amount of fore and aft play that the cartridge has while it is in the chamber. Not enough head-space and the cartridge won't chamber. Too much head-space and bad things might happen. .... |
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Thanks a lot. I am finally starting to undetstand it.
This will aso explain why it is better to just make neck resizing if you are going to use the same bolt action gun. Your shell will or should perfectly fit in the chamber. No head space issues, better ballistics. Is this correct? |
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Quoted:
Thanks a lot. I am finally starting to undetstand it. This will aso explain why it is better to just make neck resizing if you are going to use the same bolt action gun. Your shell will or should perfectly fit in the chamber. No head space issues, better ballistics. Is this correct? You should still bump the shoulder back a little bit, and size the case body down a bit as well to ensure easy chambering. With some neck sizing dies this is easy to do. Neck sized cases should fit very, very well in the chamber they were originally fired in, but you still need some clearance. As for "better ballistics", that may or may not be true. What IS true is that with minimal sizing, those cases will last for a lot of firings in that same chamber. And more consistent case dimensions certainly don't hurt your ammunition's consistency. |
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Quoted:
You should still bump the shoulder back a little bit, and size the case body down a bit as well to ensure easy chambering. With some neck sizing dies this is easy to do. Neck sized cases should fit very, very well in the chamber they were originally fired in, but you still need some clearance. As for "better ballistics", that may or may not be true. What IS true is that with minimal sizing, those cases will last for a lot of firings in that same chamber. And more consistent case dimensions certainly don't hurt your ammunition's consistency. Quoted:
Quoted:
Thanks a lot. I am finally starting to undetstand it. This will aso explain why it is better to just make neck resizing if you are going to use the same bolt action gun. Your shell will or should perfectly fit in the chamber. No head space issues, better ballistics. Is this correct? You should still bump the shoulder back a little bit, and size the case body down a bit as well to ensure easy chambering. With some neck sizing dies this is easy to do. Neck sized cases should fit very, very well in the chamber they were originally fired in, but you still need some clearance. As for "better ballistics", that may or may not be true. What IS true is that with minimal sizing, those cases will last for a lot of firings in that same chamber. And more consistent case dimensions certainly don't hurt your ammunition's consistency. This is especially true for semi-automatics. For bolt action stuff, you can just neck size, if you intend to shoot it in one particular rifle... |
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