N560 and N565 in 6.5 PRC

[Iron Worker]

I shot both Hornady and once fired Federal brass at today's range session . Hornady load was 57.2 grs of H560 behind 139gr Lupua average velocity 3183 FPS SD 12' . Just under 1/2 100 yd groups ,zero pressure signs,bolt opened smooth as silk . Federal brass is 15grs heavier that Hornady 57,2 grs of V-V N565 behind 139gr Lupua produced average velocity 3,.139 SD of 9.9 and 5/8ths 5 shot group severe Bolt lift . Shinny ejector on a couple pieces. Why with a slower powder did I have less velocity out of 28" bbl. Same seating depth .

 

[Zen Archery]

Not sure what you're asking but anytime you change anything in shooting (particularly powder) it's going to give you a different results.

 

[284ackley]

I shot both Hornady and once fired Federal brass at today's range session . Hornady load was 57.2 grs of H560 behind 139gr Lupua average velocity 3183 FPS SD 12' . Just under 1/2 100 yd groups ,zero pressure signs,bolt opened smooth as silk . Federal brass is 15grs heavier that Hornady 57,2 grs of V-V N565 behind 139gr Lupua produced average velocity 3,.139 SD of 9.9 and 5/8ths 5 shot group severe Bolt lift . Shinny ejector on a couple pieces. Why with a slower powder did I have less velocity out of 28" bbl. Same seating depth .

Federal brass had smaller internal volume. Too hot a load.

 

[RockyMtnMT]

As was said changing two things at a time makes it tough to tell what did what.

I will say that we recently learned that the PRC does not like magnum primers. It will show excess pressure without corresponding vel. We switched to lr primers from mag primers and were able to run 5g more powder and nearly 250 fps more vel with the same pressure signs on the brass. Same brass in all loads, Bertram.

 

[Seabeeken]

I shot both Hornady and once fired Federal brass at today's range session . Hornady load was 57.2 grs of H560 behind 139gr Lupua average velocity 3183 FPS SD 12' . Just under 1/2 100 yd groups ,zero pressure signs,bolt opened smooth as silk . Federal brass is 15grs heavier that Hornady 57,2 grs of V-V N565 behind 139gr Lupua produced average velocity 3,.139 SD of 9.9 and 5/8ths 5 shot group severe Bolt lift . Shinny ejector on a couple pieces. Why with a slower powder did I have less velocity out of 28" bbl. Same seating depth .

Exactly what 284A said

 

[284ackley]

As was said changing two things at a time makes it tough to tell what did what.

I will say that we recently learned that the PRC does not like magnum primers. It will show excess pressure without corresponding vel. We switched to lr primers from mag primers and were able to run 5g more powder and nearly 250 fps more vel with the same pressure signs on the brass. Same brass in all loads, Bertram.

As a general rule, most cartridges that load under 60-62grs of powder, do better with LR primers over Mag Primers. There's alot of personal preference out there, but 60 grs of the proper burn rate powder for the volume of the case will be optimum at LR primers.

 

[koonazz]

As a general rule, most cartridges that load under 60-62grs of powder, do better with LR primers over Mag Primers. There's alot of personal preference out there, but 60 grs of the proper burn rate powder for the volume of the case will be optimum at LR primers.

Does that still hold true with ball powders like Magnum and Magpro? I only ask because I have quite a bit of both.

 

[Dmagna]

Does that still hold true with ball powders like Magnum and Magpro? I only ask because I have quite a bit of both.

I always use a mag primer on ball powders

 

[koonazz]

I always use a mag primer on ball powders

As have I but I noticed Hodgdon and Nosler both show their load data with these powders with lrp instead of magnum primers. I may do work up with both and compare results.