COL obviously affects pressure, charge, velocity and ballistic efficiency. Developing new loads for Bayou bullets in S&W Mod 69 , 44mag-4.25" barrel:and 44special CharterArms Bull Dog 2.5'' barrel. Loading Unique and N105 powders.
In the S&W 69 ,have calculated that the Bullet Jump ( excluding that in the cylinder) is 0.853.For a 240grn. swc@ col of 1.610. Diameter is 0.430. Have loaded other bullets out to 1.680 and as short a 1.580. Have mocked up 2 dummys 240 @1.576 and 215@1.500. Seat depths are 0.433 and 0.433. Case capacity is now the same . Charges will now only vary only slightly ,because of bullet weight.
The real question is do you need to seat these Swc's down to about 0.030 down from top of swc's widest point or should you go below top ring and crimp in that groove? Seems going on to top of the widest point is more for semi auto's. What about pushing bullet way out as long as your crimp will hold and not deform the bullet. What really matters here? Have not loaded these shorter COL's to date.
Was surprised when Ranier 200 grain plated flat point bullets loaded @col =1.610, 16.5grns N105,.starline case, WLP primer. Was very accurate and comfortable to shoot. Other good load was Sierra 240 JHP =Col 1.610,17 grns N105, starline case, WLP primer.
For the N105 powder what is the minimum case fill % that has been experienced? With this slower powder have set my lower limit @ 80% fill? Have not gotten there yet.
44 special 2.5 inch barrel--- any suggested accurate loads COL? Unique? N105? for the Bayou 215 and 240 ? or other better bullet? my old school experience is that @ these velocities lead SWC perform well in a carry gum . opinions?
all bullets are Hi-Tek Super Coated ,color gold
Thanks for reading. Osprey