SR vs Sp primer ?

michaelcj · March 4, 2015, 07:22 PM

So what is the real difference?

I have a decent supply of both, originally purchased for reloading for my .22 Hornet… I ended up settling on the SP for my Lilgun /sierra 45gr load as it was consistently more accurate.

I'm going to start loading .38spl wadcutter loads for my PPC gun using Unique. Is there strong reason/recommendation against using the "surplus" SR primers in those "low" velocity loads?

Most of the .38 loads will be used in my Davis built PPC gun on a SW model 10 frame. It does have a main/hammer spring conversion to Coil. Will also intend on using them in my stock SW #10 2"

Thanks

Mike

michaelcj · March 4, 2015, 07:44 PM

Reference is to "Small Rifle" vs "Small Pistol" primers.

tangolima · March 4, 2015, 08:15 PM

If your gun can consistently ignite the rifle powder, and you feel confident about that, there shouldn't be problem.

-TL

mmb713 · March 5, 2015, 07:46 PM

The small rifle and small pistol primers have the same external dimensions so SR primers will fit in a 38 Special case. The small pistol magnum primer is basically identical to the small rifle primer. SR primers will work in 38 Special wadcutter loads but it will increase pressure over standard SP primers and may be less consistent to boot. You'll need to be careful as you approach maximum loads. SR primers also have a harder cup than SP primers so your revolver may or may not reliably ignite a SR primer. SP primers would definitely be a better choice but SR primers will work in a pinch, if your revolver's mainspring is strong enough to set them off.

michaelcj · March 5, 2015, 08:32 PM

Thanks folks.

Mike

Hammerhead · March 6, 2015, 02:22 AM

Due to the small case volume, .38 wadcutter loads generally do best with mild primers. SR primers are generally hotter than SP primers and may not give the best accuracy, but no realistic safety concerns.

March 4, 2015, 07:22 PM	#1
michaelcj Senior Member Join Date: June 15, 2011 Location: Lopez Island, WA Posts: 279	SR vs Sp primer ? So what is the real difference? I have a decent supply of both, originally purchased for reloading for my .22 Hornet… I ended up settling on the SP for my Lilgun /sierra 45gr load as it was consistently more accurate. I'm going to start loading .38spl wadcutter loads for my PPC gun using Unique. Is there strong reason/recommendation against using the "surplus" SR primers in those "low" velocity loads? Most of the .38 loads will be used in my Davis built PPC gun on a SW model 10 frame. It does have a main/hammer spring conversion to Coil. Will also intend on using them in my stock SW #10 2" Thanks Mike

March 4, 2015, 07:44 PM	#2
michaelcj Senior Member Join Date: June 15, 2011 Location: Lopez Island, WA Posts: 279	Reference is to "Small Rifle" vs "Small Pistol" primers.

March 4, 2015, 08:15 PM	#3
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	If your gun can consistently ignite the rifle powder, and you feel confident about that, there shouldn't be problem. -TL

March 5, 2015, 07:46 PM	#4
mmb713 Senior Member Join Date: March 15, 2011 Location: Salt Lake City, UT Posts: 421	The small rifle and small pistol primers have the same external dimensions so SR primers will fit in a 38 Special case. The small pistol magnum primer is basically identical to the small rifle primer. SR primers will work in 38 Special wadcutter loads but it will increase pressure over standard SP primers and may be less consistent to boot. You'll need to be careful as you approach maximum loads. SR primers also have a harder cup than SP primers so your revolver may or may not reliably ignite a SR primer. SP primers would definitely be a better choice but SR primers will work in a pinch, if your revolver's mainspring is strong enough to set them off.

March 5, 2015, 08:32 PM	#5
michaelcj Senior Member Join Date: June 15, 2011 Location: Lopez Island, WA Posts: 279	Thanks folks. Mike

March 6, 2015, 02:22 AM	#6
Hammerhead Senior Member Join Date: May 31, 2004 Location: Minnesota Posts: 2,432	Due to the small case volume, .38 wadcutter loads generally do best with mild primers. SR primers are generally hotter than SP primers and may not give the best accuracy, but no realistic safety concerns.