The worthiness of crimping

[gitrdun]

I had never considered crimping until I reloaded for my .444 Marlin. I was made aware of the worthiness of a "factory crimp" with these rounds. So, I expended based on those results and purchased a factory crimp die for my .375 H&H. I recently came home from the range to test some 300gr TSX loads for this bruiser. I factory crimped the rounds and found results as follows:

1. Increased velocity by 60 fps - same powder charge, recipe, etc.
2. Incredible muzzle velocity consistency - 2464, 2464, 2462, 2462 and 2464 fps. Wow, I was accustomed to a differential of 20-30 fps.
3. Grouping went from 1" (quite acceptable) to 5/8" .

I'm sold on factory crimping dies. At least for my .375 H&H. Has anyone else experienced such consistency results from factory crimping?

 

[John Y Cannuck]

I have seen a difference, but not to those extremes. That's terrific consistency.

 

[Boomer]

Over the long run I would expect you to still see 10-20 fps spread in velocity. I think you must of hit on a very consistent run of brass. It would follow that very close velocity spreads would result in very good accuracy. You certainly prove the point that when done properly, crimping is far more likely to aid accuracy rather than be detrimental.