The Accurate Reloading Forums
Light primer strikes?
06 July 2010, 22:29
Johnny JetsonLight primer strikes?
Second Newbie question:
I'm having a lot of light primer strikes and I'm not sure where to look for the source of the problem.
The gun shoots factory ammo perfectly
- My reloads all have the primer seated flush with the case bottom
- The cases that give me problems seem to average a little shorter than the ones that work
- When the failed-to-fire rounds are cycled through a different gun, about half fire.
The primers are fresh off the shelf Remmingtons from Bass Pro. no solvents, cleaners, or water anywhere near my bench.
The problem gun is a Glock 22 with the Wolf barrel.
All ideas welcome,
Thanks in advance,
JJ
The government that robs Peter to pay Paul, will surely have the support of Paul. (Shaw)
06 July 2010, 22:35
Antelope SniperAny you clean the gun, or oiled it with any new products? Specifically any heavy oil's or heavier then you've used in the past, near the firing mechanism?
06 July 2010, 23:02
onefunzr2quote:
Originally posted by Johnny Jetson:
The cases that give me problems seem to average a little shorter than the ones that work
JJ, the 40 Auto, like most straight-walled pistol cartridges, headspaces on the case mouth. If the trim-to length is shorter than specified, or you crimped the case mouth excessively, the firing pin will hit the primer, pushing the cartridge forward in the chamber too far, giving your symptoms. I would check the resized case overall length to see if they are within specs.
I always use
one of these to make sure my reloads are correct. You should too.
07 July 2010, 19:32
Johnny JetsonThanks for the help, guys.
Dave: I have suspected that this case-length thing is related to my light-strike problem, but I cornered Dillon's tech line on that question the other day and their answer was that the case length wouldn't have that effect within the range of lengths I reported.
I can't see how it would be any other way, but I'm looking at 1000 rounds of once-fired from Widner's (all of which obviously fired for someone), most of which measure .840-.845 (against the Lyman standard of .850).
I have the Dillon case gauge that you suggest, but perhaps I don't know how to use it. If I try to premeasure cases before processing, they don't fit. If I want to measure after sizing, I have to take them out of the progressive press (SQDL).
Measuring completed cartridges other than sampling for QC purposes is indicative of an unreliable process, and failed carts have to be disassembled and redone.
I'm leaning toward setting up a separate, single-stage press with a better resizing die to process incoming brass the first time after purchase.
Shooting the after market barrel and downrating my loads I'm hoping will keep the brass from deforming so much that it will create repeated problems after the initial pass through the heavy sizing.
Additionally, if it's the case that I'm over-crimping the cartridges because I have been getting misfeeds due to inadequate resizing, the separate sizing process should reduce that problem.
Any comments or advice appreciated.
Thanks, again,
JJ
08 July 2010, 07:09
Johnny JetsonWell, I hope this is my last posting on this topic. Thanks again to Dave and Sniper for taking time to help.
I think my light-strike problem originates with a case sizing problem described in another thread on this forum (heading: 40 Smith resizing?). I have detailed the results of my findings on that subject in that thread, and I'll not cross-post to repeat.
I think the light-strike issue descends from my over-crimping the cases because I was having chambering problems. As a result of the over-crimp, those cases that were able to chamber easily, dropped in a couple of hundredths too far -- out of reach of the firing pin, which is what Dave suggested as a possible problem (in spite of what Dillon's tech line insisted).
If I'm right about this, full case resizing will allow me to open the crimp a fraction and the cartridges will fire properly.
At least, that's the hope.
Otherwise, I'll be back here in a week or two with another question.
Guess I'm off to pull some bullets and rebuild some cartridges.
JJ
The government that robs Peter to pay Paul, will surely have the support of Paul. (Shaw)
08 July 2010, 08:16
Skipper488In the length of a hammer strike 0.010" is fairly significant. It doesn't sound like a lot but it's all a matter of perspective. the indention from hammer strike on my .45 acp is somewhere between 0.050 and 0.080 so a case being 0.010 short could be as muc as 20% that is enough to cause problems. I think it's the short cases. to put in real perspective I'm currently working on a machine with 0.000003 resolution making preprogrammed moves of 0.000050.
Even my spell checker wants to replace Obama, it just doesn't have any suggestions.
jerry.baldwin06@comcast.net
08 July 2010, 17:26
onefunzr2quote:
Originally posted by Johnny Jetson:
I have the Dillon case gauge that you suggest, but perhaps I don't know how to use it.
Drop the completed round into the gauge. The case head should be flush with the gauge, not higher, not lower.
If SQDL means Dillon's Square Deal B press, I have over a decade of experience with it in just about every cartridge they offer EXCEPT 40/10mm. The operation is exactly the same for them all...station #1 resizes the case diameter. Except for popping out the spent primer, it does nothing else. Since your complaint is:
quote:
I'm leaning toward setting up a separate, single-stage press with a better resizing die to process incoming brass the first time after purchase.
What is the SDB's station #1 resizing die NOT doing to your satisfaction?
As straight-walled pistol cases rarely grow in length you're kinda stuck with the less than trim to length .840"-.845" cases. Your only avenue is to readjust the crimp die on station #4 to see if a less aggressive crimp will help salvage your ammo.
Or, perhaps your after-market barrel's chamber is too long?