EXCESSIVE PRESSURE SIGNS

Sticking of cases in chamber or hard ejection are signs of excessive case expansion.

Ejector marks on the head of the case are a sign of hard extraction.

Blown primers or signs of blowing around the primer.

Primers that blow back and cause revolvers to not rotate the cylinder easily.

Head expansion or bulging near the head.

Enlarged primer pocket. This can also cause the primer to blow back.

If you find any of these signs you are pushing your luck. Stop, reduce your load, and start over.



CAUSES OF EXCESSIVE PRESSURE


There are many things that can cause you to generate to much pressure. Some of the reasons are listed below.


Lead or gap between bullet and the lands in the barrel is to small. There has to be a little room for the bullet to jump into the lands of the barrel. If there is not enough room then you will see pressures skyrocket.

The bullet may be seated to deep in the case which makes for a smaller interior case size.

Hot chamber or even extreemly hot weather can cause pressures to rise.

Using new components in a load can cause differences in pressure. Different makes of cases have slight differences in capacity. Bullets may change the gap at the lands of the barrel. Of course different weights of bullets also change pressures

Did you check your case length? If it is too long you can cause the pressures to shoot up.

To much powder. May be double charges on light loads, or your scale or powder measure not set right.

Maybe the gun has a chamber that is a little tighter, or the barrel has tighter dimensions than another gun of the same caliber.

Using the wrong data from the manual. Always check and double check. I like to use a straight edge to be sure that I follow the line across the page.

Bullet could be the wrong weight or dimension.

Powder could be wrong kind or mixed. Never mix powders. Even different batches of the same powder can cause different pressures to be developed.



If you see any of the signs listed above. STOP SHOOTING and find the cause, and correct it.


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