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View Full Version : Question about pressure signs on whisper brass


egraham
02-01-2010, 12:28 AM
I am loading aa#5 with a 208 grain amax using LC cases. I am at 6.3 grains and I am going to try 6.4 and 6.5 before I move up to aa#7.

if there is excessive pressure will the signs be the same as in a 243, 308, etc?

I am shooting a remington 700 action with douglas heavy barrel and a degroat can. I have a tubbs firing pin kit in it so the primers are always dinged pretty hard.

Thanks for any help.

Emris

HUNTER2
02-01-2010, 10:26 AM
Have the Tubbs also in a Winchester. It is smaller and makes them crater. GreTan will redo th pin hole so it doesn't do that. They say they do a band up job. I just live with it - doesn't seem to hurt anything. And yes, read the pressure the same. Loose primers act the same!:nanabang:

amafrank
02-01-2010, 01:36 PM
Yes the signs are the same...flattened primers, cratering of the primer, stiff extraction etc. The load you posted should be subsonic I believe so you might notice a supersonic crack of the bullet as well.
As for your firing pin you need to check the protrusion. If it is excessively punching the primers you need to fix it. You don't want to perforate the primers at any pressure as it will pit the firing pin and bolt face as well as venting a lot of hot gas into your face. There is a min and max spec for protrusion for every firearm and excess is bad....


Good luck
Frank

egraham
02-01-2010, 11:27 PM
at 6.3 grains with a 208 amax I am at 935fps. I want to be around 1025.

cav_scout_tj
02-03-2010, 12:01 PM
pressure in subsonics is going to far below anything you see in a full power rifle. With 208s, you should be able to run them up to 1300 or so before you see any pressure signs at all. Of course thats a lot faster than you want. Point being, yes the signs are the same, but dont expect to see any.

Think about-- 230grains at 900 fps, thats done at 45 APC pressures.