Smokeless
New member
I decided to play with some rimfire reloading recently and found dramatic improvements.
Factory Winchester white box [22wmr] 40gr hp,s had 5.7gr of a fine ball powder and were fairly consistent in charge weight. Muzzle velocity from a 24" barrel was around 1850fps. accuracy was around 1.5 inch at 50yds.
Factory powder was increased to a max of 7.0gr and 2165 fps. No accuracy test was done. That is a 300fps gain though!
Lil'Gun and H-110 were also tested with 40gr V-Max, factory 40gr hollow points, and 50gr Hornady sx's.
I was able to settle on H-110 with factory 40gr hp's at 2275fps and groups right at 1" at 50yds.
The 50gr Hornady sx bullet could be seated deep enough to work with the factory magazine if the led tip was filed off [1.335 oal] H-110 was able to produce 1905fps and groups right in the 1" area from a CZ American 455.
It still is no Hornet, but for close called in cats it should be heavy medicine!
I'm still playing with it. Factory Hornady 30gr V-max were 2400 plus fps and group very well. The gains I was able to make were 400fps over factory 40gr though and that is something worth while.
Oh and the Federal 50 were 1570fps from the 19" CZ while my reloads with 50gr Hornady sx's were 1900fps
Just sharing my experience. have fun and be safe!
******* WARNING *******
I am no expert. Just a regular guy who likes to tinker. You should not try this unless you have done your own research and feel comfortable with playing in the unknown. When in doubt, don't do it!
Factory Winchester white box [22wmr] 40gr hp,s had 5.7gr of a fine ball powder and were fairly consistent in charge weight. Muzzle velocity from a 24" barrel was around 1850fps. accuracy was around 1.5 inch at 50yds.
Factory powder was increased to a max of 7.0gr and 2165 fps. No accuracy test was done. That is a 300fps gain though!
Lil'Gun and H-110 were also tested with 40gr V-Max, factory 40gr hollow points, and 50gr Hornady sx's.
I was able to settle on H-110 with factory 40gr hp's at 2275fps and groups right at 1" at 50yds.
The 50gr Hornady sx bullet could be seated deep enough to work with the factory magazine if the led tip was filed off [1.335 oal] H-110 was able to produce 1905fps and groups right in the 1" area from a CZ American 455.
It still is no Hornet, but for close called in cats it should be heavy medicine!
I'm still playing with it. Factory Hornady 30gr V-max were 2400 plus fps and group very well. The gains I was able to make were 400fps over factory 40gr though and that is something worth while.
Oh and the Federal 50 were 1570fps from the 19" CZ while my reloads with 50gr Hornady sx's were 1900fps

Just sharing my experience. have fun and be safe!
******* WARNING *******
I am no expert. Just a regular guy who likes to tinker. You should not try this unless you have done your own research and feel comfortable with playing in the unknown. When in doubt, don't do it!
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