Quote:
Originally Posted by alwslate
1. 21gr W296 WSPM primer = 1331 fps.
2. 17.5gr 2400 CCI 400 SR primer = 1373 fps.
3. 8.2gr W231 WSPM primer = 1285 fps.
Appearance of the fired primers indicated that the 231 load was at higher pressure than the other two as the primers were much more flattened.
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I'm a little surprised you think the W231 load will generate more pressure than the other two loads according to the charge weights you list. According to Alliant 17.5gr is the Max charge of 2400 under a 125gr bullet. BTW, what did you use a SR primers with 2400 and a WSPM primer with the other loads? Alliant used a CCI500 primer in their testing so with a Max charge of 2400 and a SRP your load is above Max according to Alliant's data and it should be generating more pressure than the W231 load. Your W231 load is below Max at 8.2gr and probably in the 40,000 CUP range because Hodgdon is reporting a Max charge of 8.5gr W231 with a pressure of 42,000 CUP. They are using the same primer you used. Your W296 load is reported to generate 38,400 CUP @21.0gr using the same primer you did so your observations are spot on there. I'm just wondering about that 2400 load, I'm feeling it's at a higher pressure than the W231 load because your W231 load is below the published max by .3gr and your 2400 load is at Max but you used a SRP instead of a standard SPP like was used by Alliant. I'm guessing you are generating more pressure in the 2400 load but you won't see the pressure signs because a SR primer will handle the pressures better because rifle primers are designed to withstand much higher pressures than a pistol primer will.
You can't use primer condition as an indicator of pressure unless you use the same primers in all the loads. (especially when that harder primer not only hides pressure signs better while also increasing the pressures because it's a rifle primer)