"cookie cuttering" primers on .223 Wylde

[servicegun]

Hi folks,

I need some advice here. I reload for three of us who compete in highpower with ar-15 service rifles. One of the guns is an Obermeyer 1-7.8 twist with a Wylde chamber. The other two guns chambers were cut with a reamer similar to a 5.56 match chamber and love the current 600 yard load. When you shoot the same load in the Wylde gun it pierces the primers and makes the "cookie cutter" marks. The advice I received from some was to just back the load down. I understand that in turn will probably back the pressure down but that makes me lose velocity which I don't like because its very windy where I shoot. Can anyone explain what causes this pressure? I am assuming this is some sort of dimension issue but I am no expert.

Thanks,

Mike

 

[Dans40X]

The Oby barrel/bore is tight compared to the other unspecified barrels.
So yes,the load will have to be down loaded accordingly to eliminate blanking primers.

For verification, run the other barrels loads to the down loaded Oby Barrel loads across a chrono to eliminate all doubt.

 

[servicegun]

AhhhHa, if it has a tighter bore then that would explain everything. I was banging my head for days on this one. I love this forum!

That would mean my only option is to back the load down..which isnt a terrible thing I guess.

Thank you

 

[bigedp51]

Headspace or a weak firing pin spring are the major culprits.

 

[cmillard]

are you running moly on the bullets or running a bolt carrier weight? i have found that the bolt carrier weight really helps with the primer issue.

 

[MarkS]

servicegun,

All the info so far is very good. One more thing. What primer are you using? I see this with 6BR cases shooting heavy bulles. CCI 450 or BR4 are harder and will help from cratering.

Mark Schronce

 

[MrMajestic]

Let's not forget he is getting "Smiley Faces" also.

 

[servicegun]

I'm using Winchester primers. I was told the new brass colored Winchester primers are not as hard as the older silver colored ones but I personally dont know if there is that much difference.

The other two barrels are a krieger and a schnieder, both perform very well.

 

[6BRinNZ]

servicegun - i went from silver winchester primers to the gold coloured - same load and started blowing primers (in my varminter .223). I reworked the load with cci's...I got back to similar fps and excellent grouping with the cci's, same brass, bullet and powder. Based on my experience if you have gone from silver to gold winchester primers there is a good chance you will have a problem...I'm not sure if the gold coloured are just softer or caused different pressures for the same load. At the time I just assumed they were softer and changed them.