270 wsm primer question

Buckeyeshooter · January 30, 2013, 12:17 PM

A buddy and I are having a question of who is correct on which primer to use in his 270 wsm load. He is using win 760 powder but only has large rifle primers not the magnum ones the load manual states. First is there any risk to safety in using the large rifle primers. Second if they are safe would it just affect bullet velocity or would it cause pressure variances in chamber and barrel. I say stay with the load data. Any other votes or comments from the more experienced?

Thanks in advance

gundog5 · January 30, 2013, 02:04 PM

Magnum primers are called for in cases that hold larger amounts of powder then the standard LR primers will not effectively ignite the entire powder charge. I will not claim to be an expert on internal chamber pressure but IMO I would be wary. Use the primmers recommended for safety and piece of mind.

Brian Pfleuger · January 30, 2013, 02:19 PM

If the data calls for magnum primers, it is wise to use them. They are used to ensure consistent ignition of powder in large cases and/or charges of harder to light slow burning powders, which are typically the powders used in large cases.

It's not likely to be a safety issue, so long as you know what to do in the off-chance that the gun doesn't say "BOOM!" but it is likely to cause erratic ignition, muzzle velocity and effect long distance accuracy.

AllenJ · January 30, 2013, 02:52 PM

Completely agree with the answers above. I've read somewhere that ball powder is harder to ignite, therefore in large cases magnum primers were recommended for more consistant ignition.

January 30, 2013, 12:17 PM	#1
Buckeyeshooter Junior Member Join Date: March 15, 2009 Posts: 10	270 wsm primer question A buddy and I are having a question of who is correct on which primer to use in his 270 wsm load. He is using win 760 powder but only has large rifle primers not the magnum ones the load manual states. First is there any risk to safety in using the large rifle primers. Second if they are safe would it just affect bullet velocity or would it cause pressure variances in chamber and barrel. I say stay with the load data. Any other votes or comments from the more experienced? Thanks in advance

January 30, 2013, 02:19 PM	#3
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	If the data calls for magnum primers, it is wise to use them. They are used to ensure consistent ignition of powder in large cases and/or charges of harder to light slow burning powders, which are typically the powders used in large cases. It's not likely to be a safety issue, so long as you know what to do in the off-chance that the gun doesn't say "BOOM!" but it is likely to cause erratic ignition, muzzle velocity and effect long distance accuracy. __________________ Nobody plans to screw up their lives... ...they just don't plan not to. -Andy Stanley

January 30, 2013, 02:04 PM	#2
gundog5 Senior Member Join Date: January 27, 2013 Posts: 116	Magnum primers are called for in cases that hold larger amounts of powder then the standard LR primers will not effectively ignite the entire powder charge. I will not claim to be an expert on internal chamber pressure but IMO I would be wary. Use the primmers recommended for safety and piece of mind.

January 30, 2013, 02:52 PM	#4
AllenJ Senior Member Join Date: December 11, 2009 Location: Northern California Posts: 1,766	Completely agree with the answers above. I've read somewhere that ball powder is harder to ignite, therefore in large cases magnum primers were recommended for more consistant ignition.