piercing primers

[jkohler]

Guys
I'm looking for some thoughts on piercing primers while fire forming BR-DX brass. I pierced 6 out of 50 yesterday. The gun is on Defiance action Keriger 10tw barrel. The load was 80gr Berger .025 in the lands 31.0 Gr's vv135 205m primers and lapua brass. I did use a faults shoulder on the brass also. None of the primers where flatend at all. I have used this same load to forming brass in another BR-DX and all went just fine. IS it just the 205m primers?
Thanks

 

[alf]

Different barrel, different load. Take a half a grain out and see how they look. I use 7 1/2's for fireforming, as I have a bunch, and prefer to save my 205's for match duty. I've found that I have to shoot the brass one more time before the best accuracy shows up.

 

[fdshuster]

In addition to reducing your powder charge, check-out the report on primers. On the home page, under "Technical Articles", and scroll down to "Rifle Primer Dimensions". CCI BR4, CCI 450, and Rem. 7 1/2 are all .025" cup thickness. 205M's are .0225". The extra thickness may help.

 

[jkohler]

I am using the 205 primers for fire forming only. I tried br4's in the other rifle and the firing pin was just pushing them forward and would not fire the round. I was going to drop the charge just a bit and see.

 

[fdshuster]

I've been using Remington 7 1/2's to fire-form my 6 BRX case's. Works fine.

 

[artbosco]

I'm looking for some thoughts on piercing primers while fire forming BR-DX brass. 205m primers and lapua brass. IS it just the 205m primers?

Federal small rifle primers are thin. Try a thicker one like Rem 7.5, CCI BR4 or CCI 450. Here's are the choices. See dimension A: http://www.jamescalhoon.com/primers_and_pressure.php Otherwise, cut back on the load.

 

[DJ111]

If it is just pushing the BR4's forward and not firing then you have a headspace issue. If you are using a false shoulder you must be sizing it down to far if it is letting the case go forward and not fire.....might be why you are piercing the 205's??

 

[potatoe]

Also is your firing pin/hole bushed?

 

[jkohler]

Guys Thanks for the replies
DJ111 I have checked the head space on the rifle as I have the the reamer and gage. I am also doing the false shoulder and the brass is a good crush fit in the chamber.

Potatoe No it is not bushed. It is a custom action form defiance machine it is allready a nice fit.

I'm going to try seating the bullets just to touch the land and see if that works. Also will use some 450 primer and see if it will go bang with them and not just push them forword. As far as the 31.0 Gr's of vv135 I will try it one more time as I dont really think it is a hot load at all . Specally for fire forming to the improved brass. As I shoot it in two other factory rifles and not a problem with them even in really hot weather.

 

[lrgoodger]

You probably need to replace your firing pin at this point. It only takes a couple of pierced primers to burn the end of the firing pin. Now it is no longer round and the sharp edges on it make it pierce primers even more easily. Look at it under magnification and you will be able to see the damage.

 

[NorCalMikie]

Like DJ said. Case being pushed back on the firing pin when fired? Stuff the bullets into the lands and keep shooting.
After the cases are formed, if it keeps up, then think about changing primers.

 

[lynn]

JKohler
Antime your moving the shoulder forward you run into these kinds of issues and my vote is with DJ111 as well.
You want the rounds to chamber with some dificulty.If the bolt can be easily palmed closed your false shoulder isn't set right.If you close the bolt on a round you must fire it or take it back home and re-do the false shoulder.
If your shooting bullets and not cream of wheat you can size the necks way down as this will create a false neck behind the bullet.
All that being said make sure you lube your lugs well.
Lynn

P.S. If you don't think your rounds are being pushed for by the firing pin a quick check would be to measure the cases after removing the spent primers first.Now measure from the casehead to the shoulder to see how much variation you have.