Problem with light strikes

[hogpatrol]

Seat a new primer part way in an empty case and close the bolt. Check and see how much the primer is sticking out of the pocket. Not a 100% method of checking headspace but it may give you an indication that the shoulder is bumped too much or if you may have a headspace issue.

 

[chromatica]

Seat a new primer part way in an empty case and close the bolt. Check and see how much the primer is sticking out of the pocket. Not a 100% method of checking headspace but it may give you an indication that the shoulder is bumped too much or if you may have a headspace issue.

I like it!

 

[chromatica]

I will agree with your first sentence. I don't like the word BUMP either. Has a negative connotation to me. I prefer "setback X amount of thousandths". At least it sounds like you are doing something that you have an idea what it is doing. And maybe doing it for a reason other than it sounds catchy.
That's where the agreement ends. The OP never said 'his cases had headspace' which drives you nuts. In fact he referred to go/no gauges which have nothing to do with the brass. He didn't ask what SAAMI says or does not say.
'Killer firing pins?' What's that?
How about "I set the shoulder back X number of thousandths because of bolt closing issues and now have a failure to fire problem?"

OK, OK SAAMI spec for base to shoulder is 1.630.

http://members.saami.org/ManualsStds/CC_Drawings/Rifle/260 Remington.pdf

My case gauge measures plus or minus relative to the 1.630 base to shoulder spec.

 

[6MMsteve]

Guffer is here bahabahabaha remember the new code word for BUMPING THE SHOULDER

 

[Richard Coody]

Come on guys! "Bumping" is an accepted term in reloading. If it weren't then whey does Forster sell a Shoulder Bump Die???

simply a question of semantics. not very important really. only in guffey's world.

and all because guffey knows you can't move the shoulder of a case totally supported by the walls of a sizing die. he is correct. what you are really doing is moving a tiny piece of case wall to the shoulder and a tiny piece of the shoulder into the neck. only matters in guffey's world.

 

[kvd]

Did I bump the shoulders back too far? Is the firing pin worn? Did I set the headspace incorrectly?

chromatica,

Most likely cause is the shoulder was set back a tad to far and the firing pin could not make a firm hit on the primer. Only a few thousandths forward movement of the case can make a difference - especially if you are using primers with harder than usual cups like CCI BR primers.

I've had this happen before then I got a little to over-zealous for silky smooth bolt closure and lift. Check the fired case shoulder datum to base dimension with the Hornady tool if you have one and try not to move the shoulder back any more than 0.003" from this point - or, if the case will fit the chamber after firing - neck size only and drive on.

Ken

 

[fguffey]

Come on guys! "Bumping" is an accepted term in reloading. If it weren't then whey does Forster sell a Shoulder Bump Die???

They hired a reloader that does not understand the case has a case head, case body, shoulder and neck. All of my full length sizing dies size the case body and shoulder, if I have a die that does not size the case body and shoulder it is a body die. Problem, when I size a case body the case body is reduced in diameter, when the body of the case is reduced in diameter the shoulder movers forward and the shoulder takes on a slight radius. All of this case movement went on long before the internet. Reloaders have body dies? and bushing dies, I have had dies that sized the body and part of the shoulder for many years, I did not invent them, all that was required was a basic knowledge of dies.

Bumping is an accepted term in reloading

The term was made up by reloaders without a clue. I understand, it sounds cool to say "I bump my shoulder back .002"; and there is only one reloader on this forum that finds 'moving the shoulder back' is impossible, the rest move the shoulder back by bumping and as always I ask 'how?',

F. Guffey

 

[hogpatrol]

 

[savagedasher]

Asked a simple question it won't matter where the shoulder is if the fireing pin isn't long enough . Would that no be where you start ?
Larry

 

[dmoran]

'bump'? Bump sounds like an accident, I decide what case length I want, adjust the die and size the case. And then you are setting head space. my cases do not have head space according to SAAMI. I off set the length of the chamber from the shoulder to the bolt face with the length of the case from the shoulder to the case head.

I have killer firing pins, when the spring will not hold the pressure I get holes in the primer. When everything works the pressure inside of the primer causes the primer to conform to the firing pin.

F. Guffey

While obviously you think "killer" sounds cool, there are no mfg's of "killer firing pins" or naming of them, nor is there any SAAMI references to "killer firing pins". You are the only one.......

At the same time, there are several reloading mfg's that make references to "shoulder bump" and "case headspace". Forester, Wilson, Redding, and RCBS just to name a few that reference some of there products and instructions to "shoulder bump" and "case headspace".

fguffey's struggle with modern reloading references, words, and process. Likely always will and will continue to get all mad and upset on the internet, posting obtuse and ignorant replies on forum boards.
Donovan

 

['Freak]

Measuring from bolt face to the chamber’s shoulder datum any length at or between a minimum of 1.630” to 1.640” maximum is within SAAMI’s chamber specs.


SAAMI’s cartridge length specs measuring from case head to shoulder datum is 1.634” -.007”, or a minimum of 1.627” up to a 1.634” maximum.


If the chamber was cut to the SAAMI maximum length of 1.640” and a cartridge sized to the SAAMI minimum length of 1.627” gets chambered, then the resulting clearance between bolt face to case head is .013” (headspace), and all’s still within SAAMI’s specs, der …


Need to first find what’s your chamber’s length and then size cases to a thousandth or so shorter.

 

[Ringostar]

Measuring from bolt face to the chamber’s shoulder datum any length at or between a minimum of 1.630” to 1.640” maximum is within SAAMI’s chamber specs.


SAAMI’s cartridge length specs measuring from case head to shoulder datum is 1.634” -.007”, or a minimum of 1.627” up to a 1.634” maximum.


If the chamber was cut to the SAAMI maximum length of 1.640” and a cartridge sized to the SAAMI minimum length of 1.627” gets chambered, then the resulting clearance between bolt face to case head is .013” (headspace), and all’s still within SAAMI’s specs, der …


Need to first find what’s your chamber’s length and then size cases to a thousandth or so shorter.

Yes. Since the OP has a case length gauge, and the go gauge the the barrel and bolt were set up with. Use the go gauge in the case gauge and take a measurement. That should give you what your chamber really is, and what the sized brass needs to fit.

 

[dkhunt14]

if I have a die that does not size the case body and shoulder it is a body die




F. Guffey

Better read about dies. A Body die sizes the body and the shoulder. It doesn't do the neck. A die that doesn't size the case body and shoulder is a Neck die. Matt

 

[fguffey]

Yes. Since the OP has a case length gauge, and the go gauge the the barrel and bolt were set up with.

And then there is an old term that is new to reloadeds, if he has all of that equipment he should be able to verify the case gage. Again, if he can not verify the gage he can use the gage as a comparator. COMPARATOR, that is another one of those words that reloaders can not get a good grip on.

F. Guffey

 

[Webster]

I've been having trouble with light strikes on my .260 reloads. There were three of them in my last batch of 50. I can see there is a dimple in the primers. I disassembled each of them and they each had a full load of powder; the primers just didn't ignite. I'm wondering what the problem is. Are the primers set too deep? Did I bump the shoulders back too far? Is the firing pin worn? Did I set the headspace incorrectly? I recently replaced the Savage bolt head with a PTG bolt head, but the light strikes were happening even before the switch. Does anybody have any ideas?

If you buy a new spring make sure it is the Chrome Silicon alloy. They retain proper strength forever. Traditional carbon steel music wire springs are junk. Did you get put your old firing pin and spring in the new PGT bolt? Firing pins don't wear out. A firing pin should never be to short since they protrude about .055 - .065". It wouldn't hurt to some how check protrusion. I don't think you can seat the primers to deep. I solved a FTF problem by adjusting my priming tool. I was pushing to hard and damaging the primer.

 

[savagedasher]

If you buy a new spring make sure it is the Chrome Silicon alloy. They retain proper strength forever. Traditional carbon steel music wire springs are junk. Did you get put your old firing pin and spring in the new PGT bolt? Firing pins don't wear out. A firing pin should never be to short since they protrude about .055 - .065". It wouldn't hurt to some how check protrusion. I don't think you can seat the primers to deep. I solved a FTF problem by adjusting my priming tool. I was pushing to hard and damaging the primer.

Checking the fire pin should of happened first . Remove the bolt releas the spring and measure how far the protruding is . That would of been the first thing . Larry

 

[chromatica]

chromatica,

Most likely cause is the shoulder was set back a tad to far and the firing pin could not make a firm hit on the primer. Only a few thousandths forward movement of the case can make a difference - especially if you are using primers with harder than usual cups like CCI BR primers.

I've had this happen before then I got a little to over-zealous for silky smooth bolt closure and lift. Check the fired case shoulder datum to base dimension with the Hornady tool if you have one and try not to move the shoulder back any more than 0.003" from this point - or, if the case will fit the chamber after firing - neck size only and drive on.

Ken

How far is the fireing pin Beyond the head with the bolt released ? Larry

Good question, Larry. My calipers also function as a depth gauge and they tell me that the firing pin protrudes .072 inches above the bolt face in the fired position. Seems like that would cover a multitude of sins...

 

[chromatica]

Seat a new primer part way in an empty case and close the bolt. Check and see how much the primer is sticking out of the pocket. Not a 100% method of checking headspace but it may give you an indication that the shoulder is bumped too much or if you may have a headspace issue.

 

[savagedasher]

Good question, Larry. My calipers also function as a depth gauge and they tell me that the firing pin protrudes .072 inches above the bolt face in the fired position. Seems like that would cover a multitude of sins...

Now put two pieces of tape on a case trim to the case head and see the bolt closes if it does you have a head space problem .
Larry

 

[chromatica]

Seat a new primer part way in an empty case and close the bolt. Check and see how much the primer is sticking out of the pocket. Not a 100% method of checking headspace but it may give you an indication that the shoulder is bumped too much or if you may have a headspace issue.

hogpatrol,
This sounded like a really good idea so I did as you said. I closed the bolt on one of the offending cases with a primer partially seated. Of course it took some force to get the bolt to close. The primer appeared flush when I removed the case, but the calipers told a different story. The primer surface was sitting .008 inches below the base