Before i ask my question i will mention that i did read the post about "primers backing out". I am also having this problem and i was looking for a little more detail about headspace. I am loading 64gr of rl 22 into federal cases with cci lrm primers topped with 160 ab's. Just recently i have had primers back out and even fall out. Is is possible that the casings are worn? the gun (savage 110) isn't that old and has seen about 100 rounds. Is there anyway to check the headspace and if that is the problem, how is it corected? Thanks all
headspace and primers
- Thread starter stinky
- Start date
- Nov 4, 2004
- 25,183
- 8,462
What caliber are you shooting?
JD338
JD338
If you are loading for the 7mm Rem mag you are 1 full gr over the listed max in Noslers #5 for this bullet. I think you should back down and see if the primers stay put better. The belted mag cases headspace on the belt and shoulder set back doesn`t affect them the same as a std bottle neck case.
rick smith
Handloader
- Apr 6, 2005
- 1,249
- 0
Loose primer pockets are usually caused by overloads or brass that should have been retired. If you are loading a belted case, the first shot headspace will be controlled by the belt after that you should be headspacing on the shoulder unless you have your dies set incorrectly. If so, case head seperation may be a problem. If you are not shooting a belted case, as in 7WSM, you still could be setting the shoulder too far back. To answer your question more info would be needed, caliber, loading procedure, how many times have the cases been loaded, etc.Rick.
stinky,
You seem to have more than one question, and not all revolve around headspace.
Yes, you can buy tools to measure headspace. I do, but many people don't bother and still "adjust" it fine without actually "measuring" it.
"Headspace" is the amount of room left in the chamber for a cartridge to rattle around in - too much or too litle are both problems. Rifle makers tend to put in chambers that are large so that the rifle can chamber the longest standard cartridge that an ammo maker produces. Ammo makers, on the other hand, tend to make cartridges on the small side so that they can fit into the smallest standard factory chamber. The two approaches tend to yield okay loading ammo, but which tends to a bit more headspace than most people need for either accuracy or reliability. Reloading die makers get into the mix, also, by giving the reloader adjustment instructions that also give safe, but somewhat excessive headspace.
Reloaders can follow these instructions, or, if they're loading for just one rifle chamber in that caliber, adjust the die for appropriate headspace for that chamber. My method of doing this is the RCBS PrecisionMic (one for each cartridge), but there are others. You don't strictly need it for setting headspace, however, unless you particularly want to know how many thousandths of an inch it's set.
Non-quantitative approaches include "smoking" the neck of the cases with a candle, then observing the die adjustment until the die marks show the shoulder has been set back just a trifle (note the precise term). Another approach I've read about but haven't used involves putting tape on the case head until the bolt closes with difficulty - the tape thickness is then the headspace. There are other approaches.
Rather than for precise measurement or even setting for reloading, yes, the headspace can be checked for safety. You can buy gauges, but it will likely be much cheaper to take the rifle to a gunsmith who will use a "Go," a "No-Go," and a "Field" gauge to let you know the status of your chamber.
Jaywalker
You seem to have more than one question, and not all revolve around headspace.
Yes, you can buy tools to measure headspace. I do, but many people don't bother and still "adjust" it fine without actually "measuring" it.
"Headspace" is the amount of room left in the chamber for a cartridge to rattle around in - too much or too litle are both problems. Rifle makers tend to put in chambers that are large so that the rifle can chamber the longest standard cartridge that an ammo maker produces. Ammo makers, on the other hand, tend to make cartridges on the small side so that they can fit into the smallest standard factory chamber. The two approaches tend to yield okay loading ammo, but which tends to a bit more headspace than most people need for either accuracy or reliability. Reloading die makers get into the mix, also, by giving the reloader adjustment instructions that also give safe, but somewhat excessive headspace.
Reloaders can follow these instructions, or, if they're loading for just one rifle chamber in that caliber, adjust the die for appropriate headspace for that chamber. My method of doing this is the RCBS PrecisionMic (one for each cartridge), but there are others. You don't strictly need it for setting headspace, however, unless you particularly want to know how many thousandths of an inch it's set.
Non-quantitative approaches include "smoking" the neck of the cases with a candle, then observing the die adjustment until the die marks show the shoulder has been set back just a trifle (note the precise term). Another approach I've read about but haven't used involves putting tape on the case head until the bolt closes with difficulty - the tape thickness is then the headspace. There are other approaches.
Rather than for precise measurement or even setting for reloading, yes, the headspace can be checked for safety. You can buy gauges, but it will likely be much cheaper to take the rifle to a gunsmith who will use a "Go," a "No-Go," and a "Field" gauge to let you know the status of your chamber.
Jaywalker
- Thread starter
- #6
sorry guys but i did fail to mention that it is in fact a 7mm rem mag. I was using Alliant's recipe for the 160 part which shows the max load to be 68 gr. So why is there such a difference between Alliant and Nosler??? Secondly i will throw another variable into the mix It seems as though the belted portion of the case on some are longer than others and they are difficult to feed or eject so i pull and discard those cases. I am using a lyman AA press with RCBS FL dies if this helps at all. I'm still learning and i think this is all related somehow and i want to learn.
I believe the Alliant data you refer to is for R25 not R22.
They do though list 65 gr of R22 under a 160 gr Sierra SPBT. This is a grain more then youare useing, but the bullet is not the same. The bullet used makes a difference in the load and one should use data for the bullet they have when ever possible. The core, jacket material, bearing surface, ect all effect the pressures one gets from a load. Changeing the bullet alters all of these and you never know if you are lowering or raising your pressers with out test equipment. This is one reason for working up loads. You can use other sorces of data but watch closely for flatting primers, cratering, odd velocity readings from your croney, poor case life, ect and stop when you find any sign of pressure and back off a full gr or two.
The belted cartridges all should headspace off the belt. The definition of head space I`ve been given is the lenght from the bolt face to the point on a cartridge that stops the cartridge from going deeper in the chamber. One can alter this some with a std bottle neck case by adjusting his sizeing die and you can do this with your belted cases also. The belt though will not be touched be the sizer and you "shouldn`t" be able to cause the case to have excessive space by normal sizeing unless the chamber or case its self is not up to SAAMI spec. Sizeing the case to have minimal space between the shoulder and the chamber will improve case life. Usually less body stretch means less reworking and the chance of incepient case failure should be lessened. This however doesn`t mean over loads won`t have the case over expanding and the resizeing still working the case more then is wanted.
One of the first signs of a load that is too hot is loose primer pockets or blown primers. This can occure with old tired brass or soft cases but, normally if cases wont hold a primer after the first 3-4 loads the load is the 1st suspect. I would do as suggested and smoke or color a case shoulder with a magic marker and with the size die a turn or two off the shell holder with the ram fully raised size a case. Note the point on the neck the sizer worked and whether or not the shoulder was touched, screw the die in 1/8 turn and size once more. When you have the die hitting 1/2 or more of the shoulder (seen by how much ink or soot is removed) try chambering the case in your rifle. If the case chamber hard, give the die another 1/8 turn and retry. If the case chambers with just a slight feel of crush, lock the die and size your cases. This will have the case fit your chamber as close as possible, improve accuracy and should help case life.
Presonally I feel this is the best way to size cases for any rifle or cartridge with the exception of a bench rifle where the shooter will be useing tools and doing things to his cases the rest of us should never need to worry about.
Hope Ive helped..................
- Thread starter
- #8
i will try all of these suggestions but starting off with backing down the charge to around 62 gr. its too bad though because i was already there and the gun is shooting well where i'm at and there seems to be pressure signs exept for the primers. I should also mention that i have had primers fall out after reloading and i never gave it a second thought till now. i passed it off as not seating it all the way. I will let you know!\
thanks again to all
thanks again to all
