6BRX fireform duds

[welldone]

I was shooting some rounds today in my 6BRX . These were firecorm rounds loaded with CCI Benchrest primers, NN550 powder, 95 grain SST bullets. Out of about 15 rounds, 5 did not ignite. I use the "jam the bullet about .030 "your method and don't remember this being a problem before. Does this sound like a symtom of my fireform method or what else could ne going on?

 

[nosualc]

Assuming everything else is functioning properly, how much neck tension are you using?

If you're jamming, you need to have enough neck tension to ensure you're headspacing off the bullet.

-nosualc

 

[welldone]

Not sure. I will check and see. I know it's more than just barely held nut no a death grip. Any idwa what is a good size for good neck fension

 

[gotcha]

I don't shoot the BRX but, .002" to .003" neck tension should suffice. Any chance the brass was over annealed? Are you slamming the bolt home when chambering?

 

[bozo699]

.004 to .005 is better, flat base bullets work better then boat tail bullets and try 400 primers br4's cups are harder, also as mentioned close bolt slow and fire.
Wayne.

 

[LIUNA]

Check your cartridge overall length from shoulder to base, could you be bumping shoulder too much when sizing? and what action are you using, bolt, firing pin, etc....

 

[bozo699]

Check your cartridge overall length from shoulder to base, could you be bumping shoulder too much when sizing? and what action are you using, bolt, firing pin, etc....

Huh?.....he is fire forming 6brx brass from 6 br brass, the shoulders are already .100 short, hence why he is Jamming bullets to hold base of bullet tight to the bolt face.
Wayne.

 

[welldone]

.003 neck tension, no bolt slamming going on, Rem700 stock firing pin, proven bolt set up that functions (is clean and has no brass issues). I loaded some already formed BRX brass today and all shot great with no issues at all. I mow have loaded some more fireform loads with the same components and I will give them a try soon. Maybe I had some bad primers or somthing. We will figure this I am sure. Thanks for the input.

 

[bozo699]

.003 neck tension, no bolt slamming going on, Rem700 stock firing pin, proven bolt set up that functions (is clean and has no brass issues). I loaded some already formed BRX brass today and all shot great with no issues at all. I mow have loaded some more fireform loads with the same components and I will give them a try soon. Maybe I had some bad primers or somthing. We will figure this I am sure. Thanks for the input.

Change primers and the problem will go away probab ly bump the tension up to .004 or .005 and it will for sure.
Wayne.

 

[Killshot]

Change primers and the problem will go away probably bump the tension up to .004 or .005 and it will for sure.
Wayne.

This is The Truth.

I've used the "jam hard and shoot method" with success but I experienced the same issue as you with light primer strikes. Using Blue Box brass out-of-the-box gives me .0045 neck tension.

With this FF method, the ogive of the bullet is jammed into the lands (more than one would normally use) and this holds the case against the boltface. It normally requires some force to close the bolt when FF this way. If not, you're not into the lands as far as you think you are.
When using hard-cupped primers like CCI-450 this method of FF can allow the firing-pin to drive the case forward instead of crushing the primer into the internal anvil which starts ignition. Using softer-cupped primers alleviates most of this as welldone mentions.

Re-cocking the bolt without withdrawing the cartridge gave me 100% ignition the 2nd time.

(Note to those who neck up and down, my blow-lengths are great......

 

[davek]

Try using the falsesholder method of making your cases' Ive had no missfires making cases this way. Davek.

 

[Lapua40X]

Start at the beginning. Disassemble the bolt and clean everything inside and out. Wash it out with a good solvent/brush and use a light to check its interior so make sure it's spotlessly clean. Lube and reassemble. Of course, it does no harm to check your loading procedure at the same time, but you'd be surprised how a very small layer of crud in the bolt can drive you nuts looking for causes of misfires.

 

[Dgd6mm]

The only time I had fail to fire while forming 6MM Competition Match brass is when I did not have enough neck tension. bozo699 is spot on with neck tension and primers.

 

[welldone]

Hey guys. I loaded some rounds with .004 neck tension, .030 jam, CCI BR primers, and the fireforming went perfectly. I think in the end, I had two problems. The neck tension was too little and also on some rounds, the bullet was not seated out far enough.......no jam at all. As they say.......small groups belong to those that pay attention to small details. Thanks for the input.

 

[bozo699]

Glad it's working for you now.
Wayne.

 

[boogershooter]

Softer cupped primers were also a solution for me, the only problem was a pierced primer once in a while. If you pierce a primer clean the bolt inside and out. I think my fire form load was 29.5 Varget. Have fun with it!