rockrat
06-01-2009, 09:25 PM
Figure you guys have the same trouble trying to get decent speeds in your large capacity cases, with accuracy. Large case capacity that you don't need and don't use with your boolits.
Barrel appears to be like a Marlin micro-groove, 8 lands/grooves, but with rifling .005" deep per side.
Unfortunately, I am working in unknown territory with cast in my 50, as not too many work with this caliber, but getting close on some boolits. I am having trouble getting boolits in diameters that I think will work in the gun. All moulds cast under bore size. The first group is about the best I have gotten with my Hoch mould. It casts .513 on the body, but only .498" on the nose. My gun is .4995/.5103" with a long throat.
I think I need a bit more powder, as horizontal dispersion is pretty good, but the verticle is not so good (Flyer was first shot, but it does this when I change boolits/way I lube them--had tumbled with LLA in addition to normal lubeing, also on these). About 3/4" wide X 2.25" high. If this was a 30-06 then the powder speeds I am using would be 4198/3031/4895 equivalents. The 735gr boolit is running about 2100fps. Case is about 3/4 full. 5010 powder.
http://i34.photobucket.com/albums/d149/Bigdog337/002-6.jpg
Second is with a CBE 925gr boolit that is .498"/.511". Top right flyer is first shot and lower right flyer is my fault. Boolit is running 1560fps using WC #2. Using ACWW or WCWW opens the group. Case is about 1/2 full. 4895 powder
http://i34.photobucket.com/albums/d149/Bigdog337/003-1.jpg
Would really like a boolit that casts .513/.500 using my #2 alloy. Looking at a custom mould for that. What kind of groups do you get with boolits .001" over groove vs. .002"/.003" over groove and how about nose fit? Neither boolit is snug on the nose, rattles a bit. Throat is probably akin to a Weatherby
About the best I have done with this gun is 2.5" at 100yds with a 4895 load @ near 2300fps, until the upper group. Using 4895/MRP(4831 eq)/5010. Think the LLA might have helped with the undersized nose--just a theory.
Barrel appears to be like a Marlin micro-groove, 8 lands/grooves, but with rifling .005" deep per side.
Unfortunately, I am working in unknown territory with cast in my 50, as not too many work with this caliber, but getting close on some boolits. I am having trouble getting boolits in diameters that I think will work in the gun. All moulds cast under bore size. The first group is about the best I have gotten with my Hoch mould. It casts .513 on the body, but only .498" on the nose. My gun is .4995/.5103" with a long throat.
I think I need a bit more powder, as horizontal dispersion is pretty good, but the verticle is not so good (Flyer was first shot, but it does this when I change boolits/way I lube them--had tumbled with LLA in addition to normal lubeing, also on these). About 3/4" wide X 2.25" high. If this was a 30-06 then the powder speeds I am using would be 4198/3031/4895 equivalents. The 735gr boolit is running about 2100fps. Case is about 3/4 full. 5010 powder.
http://i34.photobucket.com/albums/d149/Bigdog337/002-6.jpg
Second is with a CBE 925gr boolit that is .498"/.511". Top right flyer is first shot and lower right flyer is my fault. Boolit is running 1560fps using WC #2. Using ACWW or WCWW opens the group. Case is about 1/2 full. 4895 powder
http://i34.photobucket.com/albums/d149/Bigdog337/003-1.jpg
Would really like a boolit that casts .513/.500 using my #2 alloy. Looking at a custom mould for that. What kind of groups do you get with boolits .001" over groove vs. .002"/.003" over groove and how about nose fit? Neither boolit is snug on the nose, rattles a bit. Throat is probably akin to a Weatherby
About the best I have done with this gun is 2.5" at 100yds with a 4895 load @ near 2300fps, until the upper group. Using 4895/MRP(4831 eq)/5010. Think the LLA might have helped with the undersized nose--just a theory.