Problem solved - I think - I hope - regarding my first shot flyers from my CZ 452.
I recleaned the barrel with JB Paste then Shooter's Choice Lead remover. Shot six consecutive 20 shot groups from sand bags over 3 days and clean the barrel with Hoppe's No. 9, patch cleaning only, between each set of 20 shot groups. All groups shot with CCI standard velocity ammo.
Results: first shot of each group cut a one inch circle at 50 yards and in most cases was touching the others shots which was my goal for a hunting rifle using relatively in expensive ammo.
Apparently, with this rifle, I have to clean the barrel to avoid these flyers. Where I went wrong in the past was that I believed that a 22 rimfire barrel should not be cleaned since it adversey affects accuracy or wasn't necessary. This was the experience I had with several of my 22 rimfire handguns that I used for 30 years in competition. I normally only cleaned them once a year when I put them away for a season. Never experienced any first shot flyers - except on rare ocassions - a "squib" load which happens with 22 ammo.
I can't claim credit for this breakthough. First, one of the member on this website directed me to Rimfire Central where they decribed the same probelm I was having. I implemented their remedy (which is quite time consuming) and it temporarily corrected the problem but it soon appeared after firing approximately 100 rounds over a period of a couple of weeks without cleaning the barrel. I was about to give up when I ran into a fellow shooter who had had the same problem with a CZ. He advised me to reclean the barrel to remove all built up lead then clean with Hoppe's after each firing session. Bingo - the problem disappear.
He claimed that the CZ bores are very tight and they quickly accumulate lead in the throat area. The reason for the extreme flyer on a cold fouled barrel was the first shot was needed to loosen the accumulated lead once the built up reached the critical point and hardened. He claimed the key to avoid flyers was to keep lead from building up in the throat. In his rifle he determined that it was approximately 70 rounds. After that, if he allowed the barrel to cold for several hours the next shot would go wild then the other shots would be fine. I don't know if what he said is technically accurate but using this method I seemed to have corrected the problem for my applications.
Now I feel reasonable confident that my first shot will go where I aim it if I do my part.
I recleaned the barrel with JB Paste then Shooter's Choice Lead remover. Shot six consecutive 20 shot groups from sand bags over 3 days and clean the barrel with Hoppe's No. 9, patch cleaning only, between each set of 20 shot groups. All groups shot with CCI standard velocity ammo.
Results: first shot of each group cut a one inch circle at 50 yards and in most cases was touching the others shots which was my goal for a hunting rifle using relatively in expensive ammo.
Apparently, with this rifle, I have to clean the barrel to avoid these flyers. Where I went wrong in the past was that I believed that a 22 rimfire barrel should not be cleaned since it adversey affects accuracy or wasn't necessary. This was the experience I had with several of my 22 rimfire handguns that I used for 30 years in competition. I normally only cleaned them once a year when I put them away for a season. Never experienced any first shot flyers - except on rare ocassions - a "squib" load which happens with 22 ammo.
I can't claim credit for this breakthough. First, one of the member on this website directed me to Rimfire Central where they decribed the same probelm I was having. I implemented their remedy (which is quite time consuming) and it temporarily corrected the problem but it soon appeared after firing approximately 100 rounds over a period of a couple of weeks without cleaning the barrel. I was about to give up when I ran into a fellow shooter who had had the same problem with a CZ. He advised me to reclean the barrel to remove all built up lead then clean with Hoppe's after each firing session. Bingo - the problem disappear.
He claimed that the CZ bores are very tight and they quickly accumulate lead in the throat area. The reason for the extreme flyer on a cold fouled barrel was the first shot was needed to loosen the accumulated lead once the built up reached the critical point and hardened. He claimed the key to avoid flyers was to keep lead from building up in the throat. In his rifle he determined that it was approximately 70 rounds. After that, if he allowed the barrel to cold for several hours the next shot would go wild then the other shots would be fine. I don't know if what he said is technically accurate but using this method I seemed to have corrected the problem for my applications.
Now I feel reasonable confident that my first shot will go where I aim it if I do my part.
