Silver Jack Hammer
01-05-2013, 02:42 PM
By now we’ve had a chance to read Dave Scovill’s article in the latest Handloader magazine “Custom Cast Bullet Loads.” Mr. Scovill’s position is that boolits sized to proper bore or better yet cylinder throat diameter get distorted when they are squeezed down when seated in re-sized brass. The softer the alloy the greater the diameter of the boolit is reduced. High pressure Keith loads obturate the base of the boolit therefore the problem is overlooked unless lower pressure loads which fail to form a gas seal are used.
So I hit the loading bench yesterday measured my .45 Colt components. I pulled a 454190 from a Starline case and compared it to a 454190 sized .454” not yet seated. Sure enough. The 454190 pulled from the case mic’ed at .456” and the not seated boolit mic’ed at .4575”. Odd dimensions since my Lyman H&I die is stamped .454”. The world is not perfect; I purchased my micrometer years ago at the local hardware store, it is a General brand micrometer. I’m using alloy from a big pot of basically wheelweight lead.
I measured the inside case diameter of a re-sized Starline case with a dial caliper and read .450”. The die is RCBS carbide. Running said case up the next die is the Dillon powder funnel and case measures inside dimension at .450” with the appropriate bell.
Testing Mr. Scovill’s theory, which he eluded to in his 1996 publication “Loading the Peacemaker, Colt’s Model P” I decided to make cartridges with oversized inside dimensions. I used the seater plug from my RCBS .45-70 die and ran the re-sized .45 Colt Starline case up. I only ran the case up the seater plug far enough to expand the case to the seating depth of the 454190 which is 1.6” COL. The inside of the case measured .456” on the dial caliper. The case looks funny with a big bulge in the middle of the case. The case had to be belled separately and then I seated a previously unseated cast 454190. And yes I am getting neck tension, I can feel it when I seat the boolit, and the boolits do not seat by hand, I have to use a press. Apply crimp. The finished product passed the chamber check in my Colt SAA 3rd gen. Repeat four more times and hit the range.
I printed a very tight group, three (3) inches at 25 yards with less than solid rest with a flier that I called when I jerked it. Too excited, shouldn’t have eaten that big candy bar before testing my only 5 in my newly discovered load. Then immediately on another target I shot five of my previously standard loaded cartridges and had a much larger group, six (6) inches. I’ve done better.
I think I’m on to something here. I’m going to construct a lot of 50 or 100 cartridges and see if the proof is in the pudding or the results were just a fluke.
To reiterate, this process is for lower pressure .45 Colt loads and lower pressure .44 Special loads. The process is a recipe necessary for offending oversized cylinder throats common on the Colt SAA. I have four Colt’s calibrated to .45 and the cylinder throats run about .456” measured on my dial caliper. For my next lot I’m going to cast 454190 in higher quality 20:1 alloy. Previous 20:1 454190 seated in tight cases showed no improvement over by boolits cast from wheelweights purchased from the local scrap metal recycling yard.
Again, I was a proponent of tight inside neck diameters to maximize boolit pull and years ago even had a ‘smith reduce a .45 Colt seater plug down for me. The issues with the .45 Colt made me a .44 Special shooter for a couple decades but I can’t stop tinkering, reading and testing.
Mr. Scovill states Mr. Keith used 16:1 alloy but his loads were hot. Keith’s loads worked because the healthy dollop of 2400 upset the base of the boolit forming a gas seal in spite of the damage the brass caused to the boolit when seated.
No one really paid any attention to this issue with hot loads, then the advent of the .44 Mag caused a swing to harder alloys in the retail market. This exacerbated the problem in .45 Colt and .44 Special’s in standard pressure loads. The SASS world shed no light on the issue; they use mouse flatulence pressures and shoot large, close targets.
Elmer used 16:1 in hot .44 Special with oversized cylinder throats but the base of the boolits obturate to form the gas seal so no one paid any attention because it’s the base of the boolit that does the steering. He got good accuracy.
Mr. Skovill states that he noted these inconsistencies as a young fledgling gun writer wanta be but dared not raise a note against the grand old man, who had been shown to be right in the end almost all of the time.
44Man’s post ‘brass and grips” learned me to not confuse the difference between crimp and case tension.
So I hit the loading bench yesterday measured my .45 Colt components. I pulled a 454190 from a Starline case and compared it to a 454190 sized .454” not yet seated. Sure enough. The 454190 pulled from the case mic’ed at .456” and the not seated boolit mic’ed at .4575”. Odd dimensions since my Lyman H&I die is stamped .454”. The world is not perfect; I purchased my micrometer years ago at the local hardware store, it is a General brand micrometer. I’m using alloy from a big pot of basically wheelweight lead.
I measured the inside case diameter of a re-sized Starline case with a dial caliper and read .450”. The die is RCBS carbide. Running said case up the next die is the Dillon powder funnel and case measures inside dimension at .450” with the appropriate bell.
Testing Mr. Scovill’s theory, which he eluded to in his 1996 publication “Loading the Peacemaker, Colt’s Model P” I decided to make cartridges with oversized inside dimensions. I used the seater plug from my RCBS .45-70 die and ran the re-sized .45 Colt Starline case up. I only ran the case up the seater plug far enough to expand the case to the seating depth of the 454190 which is 1.6” COL. The inside of the case measured .456” on the dial caliper. The case looks funny with a big bulge in the middle of the case. The case had to be belled separately and then I seated a previously unseated cast 454190. And yes I am getting neck tension, I can feel it when I seat the boolit, and the boolits do not seat by hand, I have to use a press. Apply crimp. The finished product passed the chamber check in my Colt SAA 3rd gen. Repeat four more times and hit the range.
I printed a very tight group, three (3) inches at 25 yards with less than solid rest with a flier that I called when I jerked it. Too excited, shouldn’t have eaten that big candy bar before testing my only 5 in my newly discovered load. Then immediately on another target I shot five of my previously standard loaded cartridges and had a much larger group, six (6) inches. I’ve done better.
I think I’m on to something here. I’m going to construct a lot of 50 or 100 cartridges and see if the proof is in the pudding or the results were just a fluke.
To reiterate, this process is for lower pressure .45 Colt loads and lower pressure .44 Special loads. The process is a recipe necessary for offending oversized cylinder throats common on the Colt SAA. I have four Colt’s calibrated to .45 and the cylinder throats run about .456” measured on my dial caliper. For my next lot I’m going to cast 454190 in higher quality 20:1 alloy. Previous 20:1 454190 seated in tight cases showed no improvement over by boolits cast from wheelweights purchased from the local scrap metal recycling yard.
Again, I was a proponent of tight inside neck diameters to maximize boolit pull and years ago even had a ‘smith reduce a .45 Colt seater plug down for me. The issues with the .45 Colt made me a .44 Special shooter for a couple decades but I can’t stop tinkering, reading and testing.
Mr. Scovill states Mr. Keith used 16:1 alloy but his loads were hot. Keith’s loads worked because the healthy dollop of 2400 upset the base of the boolit forming a gas seal in spite of the damage the brass caused to the boolit when seated.
No one really paid any attention to this issue with hot loads, then the advent of the .44 Mag caused a swing to harder alloys in the retail market. This exacerbated the problem in .45 Colt and .44 Special’s in standard pressure loads. The SASS world shed no light on the issue; they use mouse flatulence pressures and shoot large, close targets.
Elmer used 16:1 in hot .44 Special with oversized cylinder throats but the base of the boolits obturate to form the gas seal so no one paid any attention because it’s the base of the boolit that does the steering. He got good accuracy.
Mr. Skovill states that he noted these inconsistencies as a young fledgling gun writer wanta be but dared not raise a note against the grand old man, who had been shown to be right in the end almost all of the time.
44Man’s post ‘brass and grips” learned me to not confuse the difference between crimp and case tension.