Question about shotgun primer

[John Taddeo]

Thank you gentlemen for some very helpful info.

[J.B. Books]

Originally Posted by Jim Partlow

Paul.... Where does a roll crimp fit into the
Pressure quotient? I have read somewhere
that roll crimps offer less resistance, thus less
Pressure. Would appreciate your input.
Thanks Jim P.

Roll crimps reduce pressure slightly but it is hard to know exactly how much in each case. Personnally I will estimate/guess 500 psi on average when using it over a fold crimp recipe. Here is article from Ballistic Products with a few side by side comparisons. As you can see it can reduce pressure by as much as 1500 psi or as little as 100 psi.

http://ballisticproducts.wordpress.c...-a-fold-crimp/

[Jim Partlow]

Thanks for the reply. Jim P.

[C.O.B.]

I'm loading the 2 1/2 RST hull in everything. Your powder charge for a 7/8 oz load is higher than what I'm using for a 1oz load. I'm using 20.5gr of SR7625 with a Win 209 primer. Velocity is 1150FPS and pressure is 7400PSI. I think the hottest shotsheel primer is the Federal. Win, Rem and Cheddite 209 are all pretty equal. I have never used a CCI shotshell primer.

I like the cherrio as a filler if needed. It crushes easily and doesn't adversly effect anything.

[Paul Harm]

Thank you Pete - always thought I had read somewhere that roll crimps produced at least some lower pressures and now we see where someone tested fold/roll crimps. Plus they look " cool ". Rich, from my Alliant reloaders handbook - the CCI 209M [ magnum ] is hotter and can not be substituted for the CCI 209 - Federal 209A is hotter and can not be substituted for the Federal 209 - Rem 209 is hotter and can not be substituted for the Rem 209P. Remington primers are out of price and haven't seen them offered for awhile - I've never used a CCI primer, and the only Federal primers I've seen are the 209A, or magnum primers. That said, we have Win, Cheddite, or Fiocchi [ spelling ? ] primers left and they are all about the same for pressure. The Foicchi primers come in two sizes - 616 and 209. The 616's are used in their shells and are bigger and once used in other shells you'll have to keep on using them. The 209's are the same size as all the other 209's and no problems.