Quote:The use of pistol primers, in my opinion, has more to do with the mainspring than the powder. When the primer is lightly hit you may get erratic ignition especially with hard rifle primers.
Rod, I can't concur .... For any primer to ignite, the firing pin has to hit the primer cup -
Fast & Hard with sufficient force to crush the anvil - Period! If the anvil is not crushed, the primer compound does not ignite. Accordingly, any main spring has to have enough foot pounds of energy for the firing pin to crush the anvil and if not enough foot pounds - the anvil is not crushed and the compound is not ignited-Period. There is no better variable main spring force on the firing pin ... it either fully ignites or it doesn't
Quote:Generally Pistol primers are softer and give better ignition when the mainspring isn’t up to the task of hitting hard enough to reliably light off rifle primers.
The hardness or softness of primer cups is solely dependent on the different brands of primers with some LP & LR being the same hardness. Here's my "DMS test" of many brands of LP & LR primer cup hardness:
22 April 2015 Update – Final Version:
Test Procedure: Using a Lee Hardness Tester that measures Brinell hardness, placed a new primer on a piece of steel. Held the indent ball on the primer for 30 seconds using a 5/32” SS ball with 60 lbs load pressure
Measurement is the diameter of the indent,
smaller numbers indicate harder brass Old Additions = *
New Additions = **
Pistol Primers
**0.30 CCI 500 SP, lot K27U41
0.32 – CCI 300 LP
** 0.32 CCI 350 LPM, lot G10R
0.38 – Federal GM150 Match LP
0.38 – Sellier & Bellot SP
0.38 – Sellier & Bellot LP
0.40 – Federal 155 LP Magnum
0.40 – Winchester - Western WLP
0.42 – Federal 150 LP
0.42 - Federal 100 SP
*0.42 – Remington 1 ½ SP
0.44 – CCI 500 SP
0.48 – Remington 2 ½ LP
*0.48 – CCI LP Lot 0264 – old CCI primers
Rifle Primers
*0.24 – Herters 120 LR
0.26 – CCI BR-2 LR
0.28 – CCI 200 LR, lot H27M
** 0.28 Win-WLR, lot HNL347G
** 0.28 CCI 400 SR, lot CO1K
*0.30 – Rem UMC Nickeled High Pressure LR
** 0.30 CCI 400 SR, lot E26U
0.32 – Federal 215 LR Magnum
0.34 – Remington 9 ½ LR
*0.36 – Western 8 ½ LR
*0.38 - Rem 7 ½ Bench Rest
*0.38 – Alcan LR Magnum
*0.40 – Federal 210 LR
*0.40 – Winchester 115 Staynless LR
* 0.30 - Dynamit AG cal 6.34
* 0.32 - Dynamit AG cal 4.5
Finally, the use of pistol or rifle primers is solely dependent on the briance generated by the primer compound