well, I reloaded some 300 Rum stuff, a while ago, and decided to pull the bullets and recheck the charges. ( I was not sure my digital scale was acurate during that time) so I pulled the bullets, reweighed the charges and pressed the bullets back in. For some reason, I pressed on the bullet after I seated it to the proper length and it went down into the neck with little or no resistance. So I checked and everyone of them was like that. So I pulled out my resizing die and just partial resized them, all but 3 when reloaded were fine, great tension on the bullet. But 3 of them you could still move the bullet down into the neck. These are BRAND NEW casings from Remington, never been fired once! Why am I losing neck tension? Just because I seat a bullet and then pull it is no reason to not be able to seat another bullet if I didnt fire it right?
Measure the bullets. If they are .308" then I'd suspect that the case neck lost tension due to being worked twice when you seated the bullets the second time. Your sizing die probably sizes the ID of the neck to be roughly .300-.302". Then you seated the bullets which stretched the neck out to .308". Then you pulled the bullets, and the neck probably shrank down to maybe .305-.306" because it wasn't forced to a smaller diameter by a sizing die. So when you seated the bullets the second time the necks didn't have enough tension to hold the bullets securely. Try pulling the bullets again, then neck size the cases without the decapping pin. I'm betting that the problem will go away. Brass will rebound some, but even well annealed brass when stretched past a certain point won't rebound all the way to its original domension (think fireforming).
Wrong,once you pull the bullet the brass should be resized again . Once yo pull the bullet you lose the tension from the orginal resizing when you go to seat another bullet in it . vangusnmith
When you size the case the neck is slightly undersized and expands when seating the bullet. When you pulled the bullet you worked the neck some more even if only minimally. you'll at leat need to neck size the case to have proper tension. Partial sizing won't do the trick you need to run the case all the way through the expander to achieve good tension. weigh an empty case, bullet and primer then weigh your loaded cartridge the difference is your powder charge.
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Partial sizing won't do the trick you need to run the case all the way through the expander to achieve good tension. weigh an empty case, bullet and primer then weigh your loaded cartridge the difference is your powder charge.
His partial FL sizing is just not camming over. If what you say is true, then why can a guy shoot his gun then go home and parital FL and it works fine? I don't see your reasoning?
Ok you caught me in a brain fart. I haven't been happy with my experience with neck sizing dies and I personally associate partial full length sizing with neck sizing, my bad. If your going to run the case halfway into the die why not finish. It's my preference to full length everything to ensure reliable cycling in the field or at the bench.
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Obama=The Fourth Reich,
Just look at the parallels of the Nazi regime and the Obama Administration amazingly similar arent' they.
You certainly could FL resize them - but I understood from the original post that these were new cases. So, if it were me (and I'm lazy) I would just resize about 3/4 of the neck to restore neck tension. This is what I normally do with new brass anyway. I'm not sure if the FL die would have anything to resize on new brass.
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RE: necks loose bullets push in
ive noticed that after pulling bullets no matter the caliber the cases need to be re-sized, to not have to reprime or risk damaging primers I take the deprimer pin out of the die then go about resizing.
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necks loose bullets push in
