RCBS Rockchucker ?????

[Robert J. Adler]

OAL

Don't believe everything printed, either! Putting some dog loads together for the new Cooper in 223 and Sierra showed 2.175 for the load OAL with a 40gr BK. That puts the complete full diameter of the bullet below the neck. I e-mailed S and they said to seat just off the rifling, like always. I made a trial round and marked the bullet--found I could seat at 2.286 and still be off the lands!! I know to keep powder volume up to 100% and airspace to zero if possible. I wrote Sierra back and told them about it and they said to seat to just off the lands. The load now had the base of the bullet at the bottom of the neck--right on.
Good replies from everyone--thanks for the info.

 

[sjadventures]

I fought OAL too when I was measuring it from the point of the bullet. As soon as I went to a comparator my OAL got consistant. Check the OAL of just the bullets before you seat them and you will see why.

 

[ICANHITHIMMAN]

I ordered a comparator form hornandy and I think that is going to solve my troubles.

I relize the anneling will have no impact on the OAL consistency but it will help me extend my case life and I have to thank Winchester 69 for that tip. I have a bunch of heat sticks in my tool bucket so that is easy.

I wont be able to get a ogive to base measurement until I get the comparator but then it is something I will check.