Greetings all,
Back when CZ brought out the 455 I decided to snag one of the last 452 Americans I could find in stock. It sat mostly unused except for the occasional squirrel hunt. I noticed that it never seemed to group quite as well as my 452 Lux. Last fall I had it cut to 18" and threaded for a can. As I shot it more I got frustrated with it and decided to try bedding the stock. This was my first attempt. I purchased a pillar kit and used Devcon. Two things went wrong:
I tested 11 different types of ammo to try and find what the rifle would like. I fired 10 round groups at 50 yards and used Range Buddy to measure each group. For this initial testing I shot off of a front bag with no rear support.
I was pretty surprised, and disappointed, at how poorly the rifle grouped with typical decent ammo. Still, I decided to buy more Geco "Bolt Action" ammo and experiment with action screw torque and also test if the suppressor had any effect. All groups here were shot with a bipod and rear bag.
At this point I'm still pretty disappointed. The best performance seems to be at 20 in-lbs followed by 15 and 30. Overall there was no change from my previous test in the best tightest group. The suppressor typically increases the group size, but not always, and I would probably need to fire multiple groups to confirm that.
So what does this all mean? Do I have a turd of a rifle? Should I re-bed the action in the stock? Should I ditch the stock and put it in something more rigid like a Boyds varmint? I'm cautious about dumping too much money into this thing when I could just go out and buy a T1x or 457 and (probably) have better luck. At least with a new 457 if it has a turd barrel I could replace it easily.
Is there anything else I should be experimenting with? Any other potential causes of bad accuracy? Or am I expecting too much from this thing?
Back when CZ brought out the 455 I decided to snag one of the last 452 Americans I could find in stock. It sat mostly unused except for the occasional squirrel hunt. I noticed that it never seemed to group quite as well as my 452 Lux. Last fall I had it cut to 18" and threaded for a can. As I shot it more I got frustrated with it and decided to try bedding the stock. This was my first attempt. I purchased a pillar kit and used Devcon. Two things went wrong:
- I think one pillar is slightly misaligned. I can feel the rear action screw binding as I insert and torque it down. You can also see wear marks on it where it's rubbing against the pillar
- I didn't use a good release agent and I pulled the action too early. The result was I found a large amount of the un-cured epoxy had stuck to the action. I was able to remove it, re-coat the action with a better release agent, and put it back into the stock though. The final result is that the bedding looks like open-cell foam in the stock. Rigid, but very porous.
I tested 11 different types of ammo to try and find what the rifle would like. I fired 10 round groups at 50 yards and used Range Buddy to measure each group. For this initial testing I shot off of a front bag with no rear support.
CZ 452, 50 yards, front rest | |||
Group | Ammo | Extreme Spread | Mean Radius |
1 | CCI Blue | 5.4 | 2.07 |
2 | CCI Blue - No can | 6.22 | 2.59 |
3 | Aguila HV | 3.74 | 1.11 |
4 | Ficocchi SSHP | 3.2 | 1.03 |
5 | Aguila SV | 2.91 | 0.99 |
6 | Rem Target | 3.24 | 0.93 |
7 | Geco - Bolt Action | 1.62 | 0.63 |
8 | Geco - Semi Auto | 2.08 | 0.75 |
9 | Federal GMM | 2.17 | 0.7 |
10 | CCI 45gr HP Suppressor | 5.66 | 1.15 |
11 | Eley SSHP | 2.34 | 0.72 |
12 | Win SSHP | 3.18 | 1.05 |
I was pretty surprised, and disappointed, at how poorly the rifle grouped with typical decent ammo. Still, I decided to buy more Geco "Bolt Action" ammo and experiment with action screw torque and also test if the suppressor had any effect. All groups here were shot with a bipod and rear bag.
Front Torque | Rear Torque | Suppressor | Extreme Spread | Mean Radius |
20 | 20 | No | 1.99 | 0.61 |
22 | 22 | No | 3 | 0.79 |
22 | 22 | Yes | 4.24 | 1.29 |
25 | 25 | Yes | 4.06 | 1.09 |
25 | 25 | No | 3.21 | 1 |
27 | 27 | No | 3.05 | 0.97 |
27 | 27 | Yes | 3.74 | 1.12 |
30 | 30 | Yes | 2.59 | 0.86 |
30 | 30 | No | 1.92 | 0.7 |
32 | 32 | No | 4.31 | 1.24 |
32 | 32 | Yes | 2.95 | 0.86 |
15 | 15 | Yes | 2.34 | 0.66 |
15 | 15 | No | 2.16 | 0.69 |
17 | 17 | No | 2.56 | 0.91 |
12 | 12 | No | 2.52 | 0.69 |
15 | 15 | No | 4.6 | 1.17 |
15 | 17 | No | 3.26 | 0.85 |
15 | 15 | No | 1.72 | 0.27 |
15 | 15 | Yes | 1.91 | 0.73 |
At this point I'm still pretty disappointed. The best performance seems to be at 20 in-lbs followed by 15 and 30. Overall there was no change from my previous test in the best tightest group. The suppressor typically increases the group size, but not always, and I would probably need to fire multiple groups to confirm that.
So what does this all mean? Do I have a turd of a rifle? Should I re-bed the action in the stock? Should I ditch the stock and put it in something more rigid like a Boyds varmint? I'm cautious about dumping too much money into this thing when I could just go out and buy a T1x or 457 and (probably) have better luck. At least with a new 457 if it has a turd barrel I could replace it easily.
Is there anything else I should be experimenting with? Any other potential causes of bad accuracy? Or am I expecting too much from this thing?