Primer Flash Holes
- Thread starter RC20
- Start date
Ok, to add some data. I have seen some wild flyers out of the 6.5 on a regular basis and no where near all were my pulling a shot, good sight picture, good on the trigger (its a Savage Target trigger) etc.
So today I got two wild flyers that were not pulled and I marked the casees.
When I got home I punched the primer out and checked the flash hole.
Yep, both were .070. That makes 10 so far and I still have 50 -60 pre loaded to sort through.
I have to try to go back and correlate velocity of the shot.
Regardless the .070 flash holes are being taken out of circulation as I find them.
So today I got two wild flyers that were not pulled and I marked the casees.
When I got home I punched the primer out and checked the flash hole.
Yep, both were .070. That makes 10 so far and I still have 50 -60 pre loaded to sort through.
I have to try to go back and correlate velocity of the shot.
Regardless the .070 flash holes are being taken out of circulation as I find them.
stagpanther
New member
Besides the flash hole itself--doesn't this test also need to measure types of primers, consistency of primer cups and primers etc to really isolate the effect of the hole itself?
It won't need that if the one type of primer you use illustrates a clear statistically valid difference in performance between the two hole sizes. At that point, you can say it makes a difference, or that one primer wouldn't have shown one. If you want to know if it usually or always make a significant difference, then multiple primers and, preferably, multiple firearm testing would need to be engaged in to illustrate that.
I'll be interested to learn what the velocity mean and SD differences are.
I'll be interested to learn what the velocity mean and SD differences are.
Agreed; Just marked the non pulled flyer cases and when checked they were large hole.
and as noted, said large hold we scattered tough at least one batch if not both and until I clear and measure them this cycle (about 50 some odd still loaded) I won't know.
So in the next few weeks shoot up the rest and measure them.
After that, depending what Lapua does or does not do, I have enough I can put together a large hole shooting group and see if they are consistent in poi and the EX and SD for identical powder charges and bullet seat. I am guess I will have at least 20 to play with.
It could be a gun to gun thing, but at I just have the one gun, I have a problem.
I don't want to make them all .070 ( I could) and they are a side group to track.
If Lapua wants them back then I am good. If no I can makr the cases as not to be mixed and shoot them if I want.
and as noted, said large hold we scattered tough at least one batch if not both and until I clear and measure them this cycle (about 50 some odd still loaded) I won't know.
So in the next few weeks shoot up the rest and measure them.
After that, depending what Lapua does or does not do, I have enough I can put together a large hole shooting group and see if they are consistent in poi and the EX and SD for identical powder charges and bullet seat. I am guess I will have at least 20 to play with.
It could be a gun to gun thing, but at I just have the one gun, I have a problem.
I don't want to make them all .070 ( I could) and they are a side group to track.
If Lapua wants them back then I am good. If no I can makr the cases as not to be mixed and shoot them if I want.
9MMand223only
New member
Hello gentlemen.
I selected a compressed load for this test, that is somewhat popular and people know about because I think its in Sierra's load books.
I used Sierra Blitzking 50 grain 2.255. Did 2 loads, 10 shot strings.
It did what some of us predicted, such as Hounddawg, its lower pressure probably, and is consistently lower velocity. the impact on velocity is very similar to .1 grain of powder by drilling the hole to 100k from 80k.
I have to add to the test in future, by drilling hole to 100k, then increasing charge to 25.0 and 24.9 to get similar pressure/velocity to see if that is the reason for the change, and NOT the primer pocket.
I hope this test was interesting for you fellas, and I wish you all well
http://natoreloading.com/primerholes/
I selected a compressed load for this test, that is somewhat popular and people know about because I think its in Sierra's load books.
I used Sierra Blitzking 50 grain 2.255. Did 2 loads, 10 shot strings.
It did what some of us predicted, such as Hounddawg, its lower pressure probably, and is consistently lower velocity. the impact on velocity is very similar to .1 grain of powder by drilling the hole to 100k from 80k.
I have to add to the test in future, by drilling hole to 100k, then increasing charge to 25.0 and 24.9 to get similar pressure/velocity to see if that is the reason for the change, and NOT the primer pocket.
I hope this test was interesting for you fellas, and I wish you all well
http://natoreloading.com/primerholes/
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You could get really into depth of details and variations. However, with Primer shortage and none other than the CCI I have available, no.
With 13 cases now I can load up known good small flash hole cases and run that test on the next trip to the range.
Other than that, I really don't care particularly. I have CCI regular and some CCI magnum in small rifle.
I will continue to mark the non pulled flyers for the last 50.
The large holes I am going to have to figure out what the largest size is and uniform to that. It begins to explain an otherwise really good shooting gun.
note: This is a build I did, Target receiver aka Savage with the very light Savage Target trigger, a Shillen Bull barrel in a Boyds TH stock, NF scope with the dot.