Hey Guys,

For years I've been under the impression that when loading subsonics, (or generally) don't expand the flash hole as it takes some of the kick out of the primer and you get inconsistent detonations. recently I've seen the other argument that the bigger flash hole allows more powder to be ignited (which to me seems contradictory)
what's the latest and greatest??

Thanks!

Different people and agencies have been jimming around with flash hole size for quite a while but I haven't read anything that indicated bigger or smaller made any difference.

Never had cause to do a lot of flashhole work, are you having ignition troubles with your cases as they come from the factory?

Only time i have heard of enlarging flash holes is when shooting wax bullets in handguns.

Whu would you "need" a larger flash hole to ignite less powder?

Tried enlarging flash holes to see if there were any effects. Went up to .125" diameter.
there was no measured velocity variation, no hang fires, and no visible difference in primer pressure effect. This was conducted on a relatively small sample ;one powder, one bullet one case , one primer.
If a guy were to vary power types and charges, for example , over a larger sample size There would be greater possibility in witnessing different effects. roger

quote:

Originally posted by The Dane:
Only time i have heard of enlarging flash holes is when shooting wax bullets in handguns.

Whu would you "need" a larger flash hole to ignite less powder?

Yes it was standard practice to enlarge the primer flash hole when shooting wax bullets in revolvers, in fact wax bullet kits usually came with a set of cases with enlarged flash holes. t also apparently improved accuracy of the wax bullet too.

Wax bullets used only the primer to propel them and the enlarged flash hole helped to prevent set back of the primer to the point of binding the revolver cylinder. Primers in any cartridge do set back but the higher pressure of the burning powder in the case pushes the cartridge case back to 're-seat' the primer in its pocket.

I have heard of some who drill out the twin flash holes in Berdan primed cases so a standard de-capping pin can be used to de-cap the Berdan primer (after manually inserting the pin on its spindle in one of the offset flash holes) and it hasn't been noted that there is any change in ignition etc.

It's been a while since I did any flash hole "research", but I remember that the flash hole size is also determined by case pressure. It's possible to blow primers with a larger flash hole, as the case pressure has a "larger escape" into the primer pocket...

quote:

Originally posted by mikld:
It's been a while since I did any flash hole "research", but I remember that the flash hole size is also determined by case pressure. It's possible to blow primers with a larger flash hole, as the case pressure has a "larger escape" into the primer pocket...

roger

exactly. we use them in .45colt for Cowboy Fast Draw. I have wax bullets, 45c cases modified to accept a shotgun primer and a certain brand or primer that does not separate, Nobel Sport is one of them. The primers drop in and fall out . the wax seats by hand in the case. The goal is the hit the timer sensitized target faster than the guy next to you when a light comes on the target. Kind of like drag racing. Fast times are lower than one half second.

Years ago one could buy plastic bullets for indoor use.

For those we used magnum pistil primers in cases we made the flash hole larger.

Same with using wax bullets.

What we did was melt was in a pan to the depth of the bullet length.

We just pressed the cases onto the hard wax and they cut a bullet all by themselves.

Primers are seated last.

Wax Bullets!!! A shit load of fun in the basement, if you have a way to get the smell of burnt primer smoke vented out. They also work well for shooting wasps in the house!!