I am a relatively new reloader and am having a strange problem with my 6cm load showing signs on over pressure with a mild load of 40.0gr. The bullets will chamber just fine but after firing the bolt is sticky on extraction and I’m not sure if the brass looks ok or not.
Components:
- Virgin Lapua 6cm SRP brass
- 40.0gr of H4350
- Federal 205M small primers
- Hornady 110gr ATip seated to COAL of 2.790
- Hornady reloading manual
Equipment:
- A419 zero press
- Short Action Customs Dies
- 21st century mandrel
- Redding #1 shellholder
- SuperTrickler
- A&D FX120i scale
- Magnetospeed (40.0gr gave me an average of 2950fps over 25 rounds)
Rifle:
- Defiance deviant tactical
- 6CM Hawk hill barrel, 26”, 1:7 twist
- The rifle was chambered and assembled by Altus
The brass has not been sized, I only used a mandrel to straighten the case necks and set the bullet tension to about .0015
I took a quick measurement and it looks like the brass shoulders grew about .006-.007 after firing, is that normal?
The pictures I posted are of the fired brass, I found two of them on the right side that appeared odd to me, seems like the primer is flattened. I also see what appears to be swipes (although I’m not sure if they are false or not) and one round had what looks like soot on it after I fired it. Do the others show any signs of over pressure?
I worked up this load using the Hornady manual which shows the max at 41.7gr of H4350, so I’m not sure why I’m seeing pressure signs at this load weight. The previous lighter loads did not have a heavy or sticky bolt lift. Any help would be appreciated.
Components:
- Virgin Lapua 6cm SRP brass
- 40.0gr of H4350
- Federal 205M small primers
- Hornady 110gr ATip seated to COAL of 2.790
- Hornady reloading manual
Equipment:
- A419 zero press
- Short Action Customs Dies
- 21st century mandrel
- Redding #1 shellholder
- SuperTrickler
- A&D FX120i scale
- Magnetospeed (40.0gr gave me an average of 2950fps over 25 rounds)
Rifle:
- Defiance deviant tactical
- 6CM Hawk hill barrel, 26”, 1:7 twist
- The rifle was chambered and assembled by Altus
The brass has not been sized, I only used a mandrel to straighten the case necks and set the bullet tension to about .0015
I took a quick measurement and it looks like the brass shoulders grew about .006-.007 after firing, is that normal?
The pictures I posted are of the fired brass, I found two of them on the right side that appeared odd to me, seems like the primer is flattened. I also see what appears to be swipes (although I’m not sure if they are false or not) and one round had what looks like soot on it after I fired it. Do the others show any signs of over pressure?
I worked up this load using the Hornady manual which shows the max at 41.7gr of H4350, so I’m not sure why I’m seeing pressure signs at this load weight. The previous lighter loads did not have a heavy or sticky bolt lift. Any help would be appreciated.
Attachments
-
42516FB2-5965-46B7-BE88-80B8D5A6ECA9.jpeg551.3 KB · Views: 240
-
6B9B3D5C-E753-4348-AA1A-EEE1CE82A166.jpeg451.3 KB · Views: 227
-
C329D3D6-CD60-4626-A708-C140F3D3176B.jpeg476.8 KB · Views: 235
-
C33A15A1-F474-46FE-AB18-6C828F282A1F.jpeg334.9 KB · Views: 230
-
10DDB221-B269-4F24-A344-06B26D9E56D0.jpeg236.3 KB · Views: 243
Last edited: