There's a soft strike on the primers and measure and they're too short.  Is there anything I can do to undo the bump?  Or should I just throw the brass in my recycle pile?

Thanks!

Pull the bullets far enough to engage the rifling.

How far did you bump the shoulders???

I have found it close to impossible to resize brass too far. I'm not saying you can't do it under any circumstances, but I don't know how.

Most dies and shell holder combinations require that the ram be fully up on your press, plus the die turned down to touch the shell holder + 1/16 to 1/8 turn further to achieve enough shoulder bump. I don't know how you could get more bump than that.

Do you have gages? Buy a gage from Mo DeFina, RCBS or Hornady's Lock-N-Load system and bump your shoulder -.0015" to -.002" for a bolt action, -.003" for a semi-auto.

Does your ammo manually eject easily after being chambered, or do you have to mortar the rifle to eject stuck unfired rounds?

This. At least, assuming you're not already at or above max charge weight.

You don't have to undo the bump necessarily, and I'm not even aware of a way to do it without shooting a round. You just need the case to not get propelled forward when the firing pin strikes, and jamming the bullet will do it.

Hi everybody,

Thanks as always for the replies.  I'm trying to analyze the problem and not sure where to take it.  I think it could be because of the shoulders being too far, but perhaps I am wrong.

I'm shooting it out of a Masterpiece arms production rifle.  Using the hornady comparator, a piece of fire formed brass measures  around 1.532" at the shoulder. I just shot some FC brass that I had bumped down to 1.530" and it grouped really well.

The brass that I had problems with had a shoulder as low as 1.5165".  Again, I had a soft strike on the primer to the point that it wouldn't fire.  Overall length of these bullets is 2.792".  Creedmoor OAL is listed as 2.825", so only .03" off of MAX.

I've disassembled most of the rounds so as to retrieve the bullets (now as blems) and the powder.  The rounds eject easily and have no problems cycling, just going boom!  The load is a 140gr ELD-M using 42gr of IMR4350 which is the published max load of the Hornady book.  I've shot hundreds of rounds with it and it's consistent for me.  I've shot it with FC, Hornady and S&B brass.  I've got some Peterson brass ready that I need to start working on too.  BTW - it's factory shoulder looks to be 1.528"

So, is the shoulder the problem?  Aside from pulling the bullets out a bit further and fire forming the brass, is there a way to pull the shoulder back out?  

Thanks for the input.

Sounds like you have a bit of a headspace issue.  Even with a hard cam-over on a FL sizing die, I've never had one come up too short to fire or been below minimum specs.  I'd get a Go Gauge from Brownells, put two layers of Scotch Tape on the back of it.  If it chambers, you got problems.

Any chance the primers are bad? I agree with the above. I'd also check the FP protrusion etc.

It isn't an uncommon event to have the shoulder headspace issue when converting 6 BR to 6 Dasher for example.

So, there is a strong possibility your shoulder datum is a risk.

If you test a few by using a higher than normal neck tension and hard jam, you will have your answer.

So, if your normal prep is 0.002" then try 0.0025" or even 0.003" and jam them about 0.020". It needs to be fairly tight to close your bolt or it will not work.

You can play with both the neck tension and jam dimensions without powder or primers at first to make sure you have it set up well. Then your normal charge load will be okay for fireforming.

I would make sure the Firing Pin Protrusion is in order up front and that the spring and bolt functions are all good too.

Good Luck.

Hi all,

Thanks as always for the support and input.

I think I'm going to put them in a bucket and futz with them later.  Fortunately, I have a lot of brass to work with.  Definitely not the firing pin as all of my other rounds fire normally.