Off Center Flash Hole Affect Accuracy

Ltbull01

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How concerned should I be about off center flash holes? I have a batch of 7 Rem Mag Winchester brass that shows a number of brass like this. Thanks a bunch for your advice and experience!
 
I have been loading up norc .223 brass that have obvious off center flash holes and find they group fine...Don't imagine it helps accuracy but outta my Les Baer and Noveske they are grouping half inch with SMK's loaded on top.
 
It makes a theoretical difference I suppose, but it would be very difficult to ascertain the negative effect that an off center flash hole would have on either a target, or a game animal, provided all other dimensional elements of the cartridge were concentric and correct. A pal of mine once had a custom rifle that the maker messed up when chambering, and the chamber was cut off center. You would have thought that such a thing would have been a poor shooter, but it would stay on a dime at 100 with any bullet he chose to put through it; probably a greater testament to Ted Gaillard's barrel then to the guy who cut the chamber. Provided your decapping pin can knock out the primer, I'd ignore an off center flash hole. If the decapping pin can't find the hole, cull the case.
 
I can't see it making any difference. Many engines have off-center spark plugs. If it was bad, they'd all be centered. Rimfire ignites off center as well.
 
For a hunting rifle it's no big deal. On a real benchrest rifle it is.

Agreed. The flame from the primer will penetrate the powder column in a different way then it would with a centered hole. If everything else is equal, you will have consistent ignition with a centered flash hole. Inconsistent ignition can be seen on the target from extremely accurate rifles. Unless you're shooting benchrest or Fclass for example I wouldn't, and don't, worry about it. Consistency is everything when it comes to accurate hand loading.
 
Agreed. The flame from the primer will penetrate the powder column in a different way then it would with a centered hole. If everything else is equal, you will have consistent ignition with a centered flash hole. Inconsistent ignition can be seen on the target from extremely accurate rifles. Unless you're shooting benchrest or Fclass for example I wouldn't, and don't, worry about it. Consistency is everything when it comes to accurate hand loading.

That's the theory of it alright, but back in the day when experiments were being made with differences between front and rear priming, where the powder was initiated made no discernable difference.
 
Won't affect accuracy in the least. You'll have consistent ignition regardless of where the flash hole is located. How the flame ignites the powder makes no difference in any way, shape or form. Fire is fire.
 
I'm not an F Class shooter by any measure, so please excuse my ignorance if this is a dumb question. But being as the case of a rifle cartridge in not packed full of powder, is there not a wide variance of how the powder stacks or lays in the case as the cartridge is in the chamber? That is to say, I can't see how the powder lays perfectly consistently in every single cartridge and wouldn't this difference in how the powder bunches up have more of an impact in how the powder burns than a tiny, tiny difference in the location of the flash hole?

Again, sorry if this is a dumb question. This thread just got me wondering about how much of an impact all these little things can have on the final accurate of any given round.
 
I'm not an F Class shooter by any measure, so please excuse my ignorance if this is a dumb question. But being as the case of a rifle cartridge in not packed full of powder, is there not a wide variance of how the powder stacks or lays in the case as the cartridge is in the chamber? That is to say, I can't see how the powder lays perfectly consistently in every single cartridge and wouldn't this difference in how the powder bunches up have more of an impact in how the powder burns than a tiny, tiny difference in the location of the flash hole?

Again, sorry if this is a dumb question. This thread just got me wondering about how much of an impact all these little things can have on the final accurate of any given round.
not dumb at all, IMHO. if an off center flash hole will affect accuracy at thousandths of an inch, and thatmatters, powder not lying in the case exactly the same might be disasterous for the score. if that is what you`re going for. I believe benchrest shooters may use a filler to keep the powder where they want it. any bench shooters please correct me if I`m wrong
 
My decapper works, the Lee case trimmer gets held up a tad. I don't see a lot of definite NO GO and the interweb seems to be undecided on this so I'll take that it is a negligible impact for hunting loads...
 
not dumb at all, IMHO. if an off center flash hole will affect accuracy at thousandths of an inch, and thatmatters, powder not lying in the case exactly the same might be disasterous for the score. if that is what you`re going for. I believe benchrest shooters may use a filler to keep the powder where they want it. any bench shooters please correct me if I`m wrong

No filler used. Powder charges fill the case. In my particular rifle and current barrel, my loads put the powder half way up the neck + or - a 1/4 neck length depending where the tune is. No worries about powder laying inconsistently from case to case.
 
No filler used. Powder charges fill the case. In my particular rifle and current barrel, my loads put the powder half way up the neck + or - a 1/4 neck length depending where the tune is. No worries about powder laying inconsistently from case to case.

That's interesting. Thanks for that! So is it safe to say that the case is full enough of powder that there is never an odd air gap or bunching up of powder?
 
Nope. Always have a compressed powder charge to some degree.
In my opinion, that's the key to having a slightly off-center flash hole not affect accuracy. IOW, if the powder column completely fills the case at the web, an off-center flash hole shouldn't make much difference. However, with a less than full load, I can see--at least in theory--the potential for a decrement in accuracy. In that case, if one flash hole is below the center of the case as it lies in the chamber, it may well ignite the powder column in a slightly different way than if the off-centeredness has the flash hole above the center of the case as it lies in the chamber. Looks as if we need an empirical study on this....:)
 
Won't affect accuracy in the least. You'll have consistent ignition regardless of where the flash hole is located. How the flame ignites the powder makes no difference in any way, shape or form. Fire is fire.

THAT is an entire load of poo. Why do you think BR cases are the shape they are? The size and shape of the powder colum absolutely makes a difference to accuracy. BR cases also use small flash holes because that also affects how consistently the powder is ignited which follows on to the accuracy of the round.
 
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