I shoot a 270/300win mag and have been shooting loading this custom shooter for 8 years. I have been using lapua 300 win mag brass and as some know they discontinued it. I have reloaded the Lapua 8 times and started seeing some signs that caused concen. Bought new Nosler brass and necked it down to my .277. Same load (73 grns RL 22) 140 AB. Pop primers lef and right so i went down to 70.5 and still had problems. I also have a hard bolt closing and opening. After close exam I noticed a shoulder difference between fired and non fired.
If I chamber a live round close the bolt a couple of times it seems to help before I shoot. I leave for Sonora this Thursday 12th for a Mule deer hunt! Any suggestions??

Couple things come to my mind. Neck thickness or case to long giving you a tight hold on the bullet. If you were on the upper edge of pressure on your lapua brass and the nosler is significantly smaller capacity you could have pressure. Or maybe the lapua brass was harder and hide your pressure issue.

Can't say that would effect the shoulder. Unless you are forming a false shoulder your brass should be headspacing on the shoulder first firing. Many belt cases have more room from the shoulder to chamber shoulder than a shoulder headspace case. That is why many that fully resize a belted case and headspace on the belt often have shorter case life. After firing the brass fits your chamber. Are you sure you are just not seeing the brass fill your chamber. Second loading headspace on the shoulder.

The case length is 2.60 to 2.62 and I am at 2.60. When the rifle was built I had the smith build a collar for bullet seating and the new brass without a bullet is sticky after I neck down. I can chamber the brass close the bolt a couple of times and eliminate the sticky. Your thought on neck thickness may help.

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I can chamber the brass close the bolt a couple of times and eliminate the sticky. Your thought on neck thickness may help.

Mark the case with a marker and see where the contact is. If the brass is tight with no bullets after downsizing it will normally be tighter with a bullet in place.

I spoke with my gun smith, he beleives it is the new Nosler brass, the brass is soft and possibly thicker than lapua. He indicated the primer poping is due to soft pockets and after firing should eliminate the problem. He was not concerned with the pressue.

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Originally posted by huntnjim:
I spoke with my gun smith, he beleives it is the new Nosler brass, the brass is soft and possibly thicker than lapua. He indicated the primer poping is due to soft pockets and after firing should eliminate the problem. He was not concerned with the pressue.

Either your gunsmith is failing to completely communicate with you or you desperately need a new gunsmith.

To get to the crux of the potential problem that Ramrod was pointing out, you may have brass that is too thick in the neck. To check for this, attempt to seat a bullet by hand into a fired, unsized case. If the neck opening is too small to accept the bullet then you need to thin the neck walls.

The only reason that a load will "pop" primers (assuming that by "pop" you mean the primers are falling from the case upon firing) is excessive pressure. Once a case has been fired with pressure that is sufficient to expand the primer pocket enough for the primer to "pop" the case is forever unusable (a new primer won't stay in!). That excessive pressure may not be caused by an overload, per se, but by the excessively thick case neck binding on the bullet and not allowing it to move forward freely upon firing.

Overly thick case necks may or may not be your problem -- it is extremely difficult to diagnose such a problem with only a cursory description and no opportunity to examine the physical evidence throroughly. But your description does tend to indicate thick case necks as a prime suspect.

Stonecreek,
Remember that even without the bullet but after I have necked down the case from .30 to .277 the bolt is hard to close. After i close the bolt a couple of times this releaves the sticky bolt not freely but not nearly as sticky. so i am thinking it is the case shoulder, am I wrong.
You do have a point on reseating into a fired case before resizing. the bullet takes force instead of just falling in.

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Remember that even without the bullet but after I have necked down the case from .30 to .277 the bolt is hard to close. After i close the bolt a couple of times this releaves the sticky bolt not freely but not nearly as sticky. so i am thinking it is the case shoulder, am I wrong.

You seem to have 2 problems. Your not wrong. Closing the bolt a few times will size the brass by pushing the shoulder back. I suggest giving your FL die an extra 1/8th turn down. Then, when sizing a case, look to see if there is day light between the shell holder & die. There should not be any. 2nd- Neck diameter to large or a donut has formed at the neck/shoulder junction. This can pinch the bullet in the case on chambering. Pressure will be high.

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Originally posted by 243winxb:

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Remember that even without the bullet but after I have necked down the case from .30 to .277 the bolt is hard to close. After i close the bolt a couple of times this releaves the sticky bolt not freely but not nearly as sticky. so i am thinking it is the case shoulder, am I wrong.

You seem to have 2 problems. Your not wrong. Closing the bolt a few times will size the brass by pushing the shoulder back. I suggest giving your FL die an extra 1/8th turn down. Then, when sizing a case, look to see if there is day light between the shell holder & die. There should not be any. 2nd- Neck diameter to large or a donut has formed at the neck/shoulder junction. This can pinch the bullet in the case on chambering. Pressure will be high.

243 that is the problem, after close exam I have a donut right after the shoulder on the neck. After I fire the round this is eliminated for next load.

A true donut is when the neck wall is thicker than the rest of the neck. Part of the shoulder can move into the neck area. I feel donut only goes away with reaming or outside neck turning. Neck wall thickness in normally around .013" to .015" on standard cartridges.

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Originally posted by huntnjim:

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Originally posted by 243winxb:

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Remember that even without the bullet but after I have necked down the case from .30 to .277 the bolt is hard to close. After i close the bolt a couple of times this releaves the sticky bolt not freely but not nearly as sticky. so i am thinking it is the case shoulder, am I wrong.

You seem to have 2 problems. Your not wrong. Closing the bolt a few times will size the brass by pushing the shoulder back. I suggest giving your FL die an extra 1/8th turn down. Then, when sizing a case, look to see if there is day light between the shell holder & die. There should not be any. 2nd- Neck diameter to large or a donut has formed at the neck/shoulder junction. This can pinch the bullet in the case on chambering. Pressure will be high.

243 that is the problem, after close exam I have a donut right after the shoulder on the neck. After I fire the round this is eliminated for next load.

I agree donuts don't go away unless you neck turn or neck ream. If you have a donut after you size the case it is on the outside of the case because the expander pushed it there. After you fire the cartridge the donut is on the inside because the pressure pushing the case against the chamber walls pushed the donut to the inside. You need to neck turn the cases that are good and the ones that popped the primers you should throw away.

I live at 7600 feet so my loading bench as well as my 200 yard range is at the same elevation. I leave in the morning for a mule deer hunt in western Sonora Mex. the elevation will average a little less than 2000 feet. I would assume the pressure would be greater at lower elevation?

It sounds like you have thick necks (ream or cut) and you are trying to crank up new brass without the benefit of being fireformed to your chamber.
just a quick thought,,, Jim

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Originally posted by huntnjim:
I live at 7600 feet so my loading bench as well as my 200 yard range is at the same elevation. I leave in the morning for a mule deer hunt in western Sonora Mex. the elevation will average a little less than 2000 feet. I would assume the pressure would be greater at lower elevation?

No, the elevation will have no effect on pressure, but if the temperature is substantially higher you could experience noticeably higher pressures.

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Either your gunsmith is failing to completely communicate with you or you desperately need a new gunsmith.

+1 His comments as stated leave me concerned.