Primers, Sm Pistol vs. Sm Rifle

poperszky · June 19, 2001, 10:02 PM

Was listening to several people at steel challange tonight and most of them said that they had stopped using small pistol primers and were using small rifle primers instead. I assume it was to get more power out of the round. But don't you run into over pressure problems? What is the real benefit?

Bompa · June 19, 2001, 11:14 PM

I believe the idea is if you are using super loads there is less chance of pierced primers..The rifle primer being made of harder metal..

labgrade · June 19, 2001, 11:25 PM

Bompa's on target.

Too, some have recommended pistol primers in rifle-type calibers in Contenders - apparently, being softer, they'll allow you to see pressure signs more readily ....

Intel6 · June 20, 2001, 03:31 AM

The use of rifel primers started when the IPSC shooters started loading up the .38 Super to higer levels in order to make the compensator work better. Many shooters started having problems with the primer cups extrude back into the FP hole int he breach face and when the barrel unlocked a small piece of the primer cup was sheared off and often cause the FP to stick when enough of the cup material was sheared off.

They found that using the thicker rifle primers helped cure that problem along with using an oversize firing pin and precisely fitting it to the FP hole in the slide.

THe rifle primer doesn't cause any "pressure" problems because you basically work up your load with them.

Pampers · June 20, 2001, 08:20 AM

I had the same primer extrusion problem while working up a load for .45 Super. I cured it by modifying the cases to accept large rifle primers. This consisted of deepening the primer pocket circa .006" using a Sinclair primer pocket Uniformer. That cured the problem, along with the added benefit of more uniform ignition as demonstrated by a great reduction in standard deviation coupled with a slight DECREASE in velocity.

Triton ammo must have drawn the same conclusion because they produced their .45 Super twin, the .450 SMC, with a small primer pocket.

Yr. Obt. Svnt.

**Mal H** · June 20, 2001, 10:32 AM

Pay close attention to what Intel6 said - don't just substitute the SR primer for a SP in a given load. You must work up to a good safe load.

Hemphill · June 21, 2001, 02:32 PM

Intel6 hit the nail on the head. I use sr primers in my 40 loads for IPSC just for that reason. It also allows for the use of less powder. If you are going to use them, be sure to work up to the load, an make sure you can ignite the reliably with your pistol. Many of the tuned revolvers I have shot require federal small pistol primers because the mainspring has been lightened so much that nothing else is reliable.

WESHOOT2 · June 22, 2001, 10:37 AM

Just develop your loads with one primer; I use SR for extreme .355"-bore IPSC Major loads (9x21, 38 SUPER).

Intel6 · June 22, 2001, 06:52 PM

WESHOOT2,

Yeah! Big brain to fill the big head I am getting by all you guys saying how right I am

I was just the quickest guy to the draw that time

June 19, 2001, 10:02 PM	#1
poperszky Senior Member Join Date: December 31, 2000 Posts: 120	Primers, Sm Pistol vs. Sm Rifle Was listening to several people at steel challange tonight and most of them said that they had stopped using small pistol primers and were using small rifle primers instead. I assume it was to get more power out of the round. But don't you run into over pressure problems? What is the real benefit?

June 20, 2001, 08:20 AM	#5
Pampers Senior Member Join Date: October 8, 2000 Location: In the Lost State of Franklin Posts: 482	LR/LP too! I had the same primer extrusion problem while working up a load for .45 Super. I cured it by modifying the cases to accept large rifle primers. This consisted of deepening the primer pocket circa .006" using a Sinclair primer pocket Uniformer. That cured the problem, along with the added benefit of more uniform ignition as demonstrated by a great reduction in standard deviation coupled with a slight DECREASE in velocity. Triton ammo must have drawn the same conclusion because they produced their .45 Super twin, the .450 SMC, with a small primer pocket. Yr. Obt. Svnt. __________________ Your Most Humble & Obedient Servant Fred J. Drumheller NRA Life NRA Golden Eagle

June 22, 2001, 10:37 AM	#8
WESHOOT2 Senior Member Join Date: February 20, 1999 Location: home on the range; Vermont (Caspian country) Posts: 12,923	Intel6 = BIG BRAIN Just develop your loads with one primer; I use SR for extreme .355"-bore IPSC Major loads (9x21, 38 SUPER). __________________ . "all my ammo is mostly retired factory ammo"

June 19, 2001, 11:14 PM	#2
Bompa Senior Member Join Date: June 10, 2001 Location: western Mass. Posts: 135	I believe the idea is if you are using super loads there is less chance of pierced primers..The rifle primer being made of harder metal..

June 19, 2001, 11:25 PM	#3
labgrade Member In Memoriam Join Date: November 29, 1999 Location: west of a small town, CO Posts: 4,346	Bompa's on target. Too, some have recommended pistol primers in rifle-type calibers in Contenders - apparently, being softer, they'll allow you to see pressure signs more readily ....

June 20, 2001, 03:31 AM	#4
Intel6 Senior Member Join Date: October 14, 2000 Posts: 426	The use of rifel primers started when the IPSC shooters started loading up the .38 Super to higer levels in order to make the compensator work better. Many shooters started having problems with the primer cups extrude back into the FP hole int he breach face and when the barrel unlocked a small piece of the primer cup was sheared off and often cause the FP to stick when enough of the cup material was sheared off. They found that using the thicker rifle primers helped cure that problem along with using an oversize firing pin and precisely fitting it to the FP hole in the slide. THe rifle primer doesn't cause any "pressure" problems because you basically work up your load with them.

June 20, 2001, 10:32 AM	#6
Mal H Staff Join Date: March 20, 1999 Location: Somewhere in the woods of Northern VA Posts: 14,080	Pay close attention to what Intel6 said - don't just substitute the SR primer for a SP in a given load. You must work up to a good safe load.

June 21, 2001, 02:32 PM	#7
Hemphill Senior Member Join Date: April 21, 1999 Location: Reno, NV, USA Posts: 116	Intel6 hit the nail on the head. I use sr primers in my 40 loads for IPSC just for that reason. It also allows for the use of less powder. If you are going to use them, be sure to work up to the load, an make sure you can ignite the reliably with your pistol. Many of the tuned revolvers I have shot require federal small pistol primers because the mainspring has been lightened so much that nothing else is reliable.

June 22, 2001, 06:52 PM	#9
Intel6 Senior Member Join Date: October 14, 2000 Posts: 426	WESHOOT2, Yeah! Big brain to fill the big head I am getting by all you guys saying how right I am I was just the quickest guy to the draw that time