Rimfire Rising Point of Impact

[crazyjjk]

I have a CZ 452 Silhouette rifle which I have been trying to use for rimfire silhouette. The gun will group extremely well keeping almost all different types of ammo under 0.5 inch at 50 yds. The problem is that as I shoot it the point of impact keeps rising. I will sight this rifle in at standard rimfire silhouette ranges and after about 200 rounds or so I find that the point of impact has risen. I have about 1500 rounds through this rifle and the point of impact has risen around 8-10 inches total at 100 meters. The last time I sighted it in was approximately 150 rounds ago and it is now shooting another 1+ inches high at 100 meters. The groups are still tight and windage has not changed since I first sighted the rifle in. The ammo I use is all the same lot # bought in a case of 5000. I shoot this ammo out of two other rifles and have no problem. I have changed scopes (currently has a 16X leupold) and scope mounts and it still does it. I posted this on the forum over a RimfireCentral and they all said it was the barrel breaking in. By 1500 plus rounds already I think it should be broken in already. This problem is driving me nuts (its not a long drive) as I am continuously second guessing my self on the firing line and I'm not that great a shot anyway. Any suggestions help would be greatly appreciated.  :?   > John

[Iowegan]

I would disagree with the "break-in" theory.  I have a CZ 452-2E that did the same thing. I found the stock had warped a little and was pushing up on the barrel. I put a thin washer on the front stock screw between the stock and receiver. This lifts the barrel and free floats it. Accuracy and POI came back to normal. Theses CZs are real tack drivers.

[gunnut69]

The CZ's are great rifles(I have 5 as of now) but they like Anschutz use some type of Lacquer as a finish.  Poor stuff at best..  It will usually not seal well enough and the wood will move.  I would be Crazy's right..  The washer is a temporary fix though.  If the movement stops then removing the offending wood in the barrel channel is indicated.  While your at it, upgrade the finish over the entire stock, including the inletting.. You'll not regret it.

[crazyjjk]

Only problem is the Silhouette does not come with a wood stock. It is one of their synthetic (plastic) stock models. Barrel is floated all the way to the lug.

[Iowegan]

Guess we blew that theory! I'd still be suspicious of the stock. Loose screws maybe. Composite stocks can still warp. Try the business card trick and see if you can slide the card under the barrel, all the way from the end to the lug. All it takes is a little contact to move the barrel a few thousandths. If you take the action out of the stock when cleaning, it may not be getting tightened down the same each time.

The scope and mount are always suspect, but then you changed those.

Are you cleaning it thoroughly? Have you damaged the crown?

Your turn Gunnut69.

[gunnut69]

I'm not familior with the CZ plastic stocks but if the barrel isn't being pushed up, perhaps the action is going down.  Is the stock collapsing the stock or spreading it open, allowing the rear of the reciver to sit lower and lower.  I saw a tupperware wonder once that was so flimsy the action screws warped the stock when they were tightened.  To check a piece of small diameter tubing around the rear action screw between the action and the bottom metal.  I've used a piece of aluminum arrow tubing for similar problems before.  Your local archery retailer with a cut off saw will have all the pieces you will need.  Put the spacer around the rear most action screw and tighten.  You may have to experiment to get the tubings length right but when it all comes up tight resight the rifle and run a few hundred rounds thru it.  Bet the zero stops moving.. Let us know how it works..

[crazyjjk]

Thanks, I will try those suggestions. I have never seen anything like this before. The rifle shoots really tight groups but this POI change has been driving me nuts. Never have seen any rifle rimfire or centerfire change POI this much and in the up direction with out shifting left or right at all. I have noticed that while I am shooting it the POI does not change but when I put it away and take it out again the POI changes. It is not cleaning that is causing this as for rimfires I only clean the bore of my rimfires a couple times a year as the copper fouling isn't there. I am beginning to think as you have suggested that it is the stock. My theory is that the stock has not cured fully from manufacture and when it sits in my gun safe with it heated golden rod humidifier the stock is still curing. Just a theory though.
Again thanks for the help. I figure if anywhere the guys at Graybeard could help me figure it out.

[gunnut69]

Good luck and be sure to keep us posted.  This is a real head scratcher!!

[crazyjjk]

Took the stock off and stuck it in the oven for a couple of days at approximately 125-150 F. Thinking that it might be a uncured stock. Put it back on the rifle making sure barrel was floated and it was not binding anywhere. After 200 rounds the point of impact has risen another 2 inches.
E-mailed CZ and their suggestion was to pillar bed the gun. I was a little ticked off at this as this is a new gun and shouldn't need this. (Kind of like buying a new car and them telling me I have to buy new aftermarket engine because my new car won't run with their new engine). Also it was my impression that pillar bedding is to help wring out the last little bit of accuracy from a rifle, not correct a POI that has changed over 10 inches in elevation in less than 2000 rounds. Can say one thing, I own one centerfire 550 and a couple of CZ rimfires and after the little service, or should I say lip service I got from CZ I will not be buying anymore of their products. Beginning to believe their are some internal stress issues with the barrel.  I don't know of anyone who makes aftermarket barrels for the CZ because they are threaded in with a metric thread. I would be tempted to go the aftermarket barrel route if I could find one. All I can say is I am very disappointed in a company  that normally makes a fine product. They should learn they not only need a good product but good service. I am not asking them to replace the rifle but they are unwilling to admit that there might be a factory problem and take a look at it  I will keep you posted if I ever figure this out. >John

PS: On close inspection the muzzle end of the barrel has a lot of pitting and voids in it that are factory blued. When I asked CZ about this there response was that normal on all CZ rimfires.  No pitting or voids are in actual crown or rifling.

[gunnut69]

It is a misconception that pillar bedding is to improve accuracy. Glass bedding a rifle CAN improve the accuracy but pillar bedding just creates a non-compressable tube around the action screws so that tension on these screws over time doesn't crush the wood between the action and the floorplate. This doesn't inprove the accuracy it just keeps it from getting worse. If the barrel were changing due to the stresses of firing I would expect it to change as you shoot. Since it isn't I still believe its a stock problem. Could the constant screw tension over the time spent in the safe be causing the stock to changes shape? Put in temporary pillars made from arrow tubing. Bore the screw holes out a bit and insert arrow tubing that is large enough to slip over the screws and cut to length. This will eliminate the possibilty of the stocks changing and altering the pressure or tension on the barrel. Sybthetic stock quality varies from the very good to the mediocre. I personally dislike them all, opting instead for laminates if more stability is needed. I believe if the rifles shooting well I'd even consider glass bedding the action and pillar bedding the screws. This should stabilize the movement. The temporary pillors will give you a demonstration of the rifle with the stock stabilized.  Of course one could just buy a 1700 series Anschutz..  Just one more little thing. If the bullet impact has been continually rising and the stock IS at fault, there should be some sign in the inletting of changes taking place in the stock. If nothing else the gap between the barrel and it's channel should be changing.

[crazyjjk]

Be honest with you I wish CZ did have a laminate stock as I am of the same opinion as you. As for getting a 1700 series Annie, I am kicking myself for not doing this in the first place. The only reason I went with the CZ is I also shoot indoor sporter rifle in the winter and the Annie will not make the 7.5lb weight limit. If I could find a Annie series 1700 with single stage trigger I would probably get rid of this rifle right now. As for observing any changes in the stock, I can not see any significant changes or stock movement. This is what makes this rising POI so frustrating. It justs frosts my buns that I have to do so much to get this rifle to even shoot. I like tinkering with guns to get better accuracy. I don't like to be put in the position of tinkering to fix something that should not be happening at all. Especially on a new gun. Again thanks for the help and looks like I will be either pillar bedding it or trading it. Again thanks for your help.

[Steel killer]

I don't think you have a stock problem. I would still glass bed the action,and fill the fore arm with bedding material. You can use tape on the barrel to free float it (about three or four layers). I think your problem is scope related, barrow a proven scope and retest.   Light and temp will cause a POI change during the course of the day , My early am sight setting are often 1 to 1 1/2 moa higher than mid day setting (8 am vers 2 pm ). Different ranges may require different settings, my jacksonville settings are different than my Winnsborrow settings.

steel killer

[crazyjjk]

I don't think you have a stock problem. I would still glass bed the action,and fill the fore arm with bedding material. You can use tape on the barrel to free float it (about three or four layers). I think your problem is scope related, barrow a proven scope and retest.   Light and temp will cause a POI change during the course of the day , My early am sight setting are often 1 to 1 1/2 moa higher than mid day setting (8 am vers 2 pm ). Different ranges may require different settings, my jacksonville settings are different than my Winnsborrow settings.

steel killer

I have tried three different scopes (leopold, Weaver, Sightron) and 2 mount combinations. I have had to resight this rifle over a dozen times and have done it both morning and evening. Everytime after a 100 rounds or so the POI rises an inch or more. I even let the rifle go 600 plus rounds without changing anything or removing it from the stock just to see if the rise in POI would stop. I had to resight the rifle 4 times with an average of 2 inches rise in POI each time with no indicator that it was going to stop. The strange thing is the POI change is only in the upward direction. It hasn't ever changed left or right or ever went downward.  I know it is probably something very obvious that I am overlooking I just have not figured it out. The thing is that these POI rises are not small. As I said above the POI at 100 meters changed a total of "8 inches" in 600 rounds. You would think I would be able to see some change in the stock or action movement in the stock to get that kind of shift, but I just don't. Thanks for your help and all the suggestions as this has been the most frustrating rifle I have ever owned.>John

[fuzzy]

Is there a chance that someone is playing head games with you . And it not gun at all. Just a thought Rich

[gunnut69]

I need a little clarification. You say it changes point of impact after a few hundred rounds are fired.  Is it shooting to a dofferent POI at the end of the few hundred rounds or after you put in the vault for a coupkle of days and return to the range?  As a test, fire 300 rounds. then lock the rifle in a case for 3 days. Shouldn't cause it any harm. Keep the keys in your pocket. Check to see if the POI has changed.  If I found someone altering my sights, I'd be way beyond annoyed...  Also, don't put it in the vault. You might try this first. Make a note of the elevation knob settings and follow your normal routine. Before firing the bext time, check to see if the sights have been altered.  If nothing shows, try the arrow tubing to stabilize the stock compression between the action and the bottom iron. Yours is the first real complaint I've seen concerning major problems with a 452.  The folks locally who have the same rifle as yours are all extatic with them.  Accurate and stable only needing a trigger tune up...(spoke with 6 current owners).

[crazyjjk]

Wrote to CZ about this rising POI problem. Their reply was to pillar bed my rifle.
Wrote to CZ again about this rising POI issue stating I was dissappointed that I should have to do this much work (scope and mount switching, stock relieving, their suggestion of pillar and glass bedding) just to get one of there new rifles to just shoot acceptable. More out of principle of standing behind your quality than the actual work. Here is the reply I received from CZ.

From: "Mike Eagleshield" <gunsmith@cz-usa.com>
To: "'Info'" <info@cz-usa.com>
Sent: Monday, July 12, 2004 9:56 AM
Subject: RE: FROM CZ-USA WWW - Disappointed with CZ


> Thanks for the feed back. Good luck and good shooting.


Not much in the way of customer service. Very dissapointed will not be buying anymore CZ's. They lost a customer who buys three or four firearms a year. Lately about 1/2 of these have been CZ's both rimfire and centerfire. They lost a decent customer who will not hesitate to tell others of his view of CZ service.

[crazyjjk]

I know you guys are probably sick of this thread already but I wanted to let you know I wrote a letter to CZ expressing my dissatisfaction with the customer service I received. I feel a normally excellent company really fell down on the job this time. I will post any replies I get from CZ in this thread if I receive any. Thanks for bearing with me.>John






Dear President of CZ-USA:

I am writing this letter to voice how dissappointed I am with CZ-USA customer service. In April I purchased a new CZ 452 Silhouette at a gun show in Syracuse NY with the intention of using it in our upcoming silhouette season. I set the rifle up with Leopold target scope and sighted it in at all four banks of animals. Upon shooting in my first match I found that the rifle was shooting significantly higher than when I sighted it in. Went back a sighted it in and found it was shooting 4 inches higher than the last time. I resighted it in and went to the match next week. While at the match I found the rifle was shooting high again. To make a long story short this trend keeps continueing through 3 scope and two scope mount changes along with trying to relieve any binding in the bedding and checking screw torque. This problem is totally unacceptable for silhouette shooting for which this particular model is marketed for.
Upon writing your company I received a reply from your gunsmith that said I needed to pillar bed my gun to make it shoot. I wrote back stating my opinion that I felt that I did not believe a consumer should have to go through such drastic measures to maybe make a new rifle work for what it was designed for. We are not talking slightly larger groups or something else anal we are talking about regular point of impact changes measured in inches.
Upon receipt of this second email your company wrote back "Good luck with you shooting" (I have both emails your company sent me along with my emails sent to CZ if needed.)
I feel this was a total brush off of me as a customer with a legitimate problem. Also I had posted this problem on the CZ forum trying to figure out how to fix it under a thread rising POI. Later on in the posts on this thread when nothing seemed to work and I contacted CZ, I posted your companies reply. I feel that the 1600 plus viewers of this thread were shocked that your company with usually a good product and normally good customer service would give me such a non answer as "good luck shooting", and that I the customer was given the brush off. I was not asking for a replacement or wanting my money back I just wanted some help and I felt your companies response was totally inappropriate.
Normally your company makes a great product, as I can attest because I have your centerfire rifles. But every company has a defect or problem occassionally with one of its products. It is how a company resolves the issue when a problem arises that sets it apart. I feel your company really fell down on the job this time.

Sincerely,
John J. Kaufman

[gunnut69]

Have you tried the temporary pillars to see if they help. It would certainly prove a theory.  I've not had experience with CZ customer service, sounds like I don't want to!

[crazyjjk]

Never received a reply from CZ that they even received  my letter so I resent it today just in case I did something wrong the first time. Hope they do not become a big black hole in consumer relations like many other of the gun companies have become.>John

I know you guys are probably sick of this thread already but I wanted to let you know I wrote a letter to CZ expressing my dissatisfaction with the customer service I received. I feel a normally excellent company really fell down on the job this time. I will post any replies I get from CZ in this thread if I receive any. Thanks for bearing with me.>John






Dear President of CZ-USA:

I am writing this letter to voice how dissappointed I am with CZ-USA customer service. In April I purchased a new CZ 452 Silhouette at a gun show in Syracuse NY with the intention of using it in our upcoming silhouette season. I set the rifle up with Leopold target scope and sighted it in at all four banks of animals. Upon shooting in my first match I found that the rifle was shooting significantly higher than when I sighted it in. Went back a sighted it in and found it was shooting 4 inches higher than the last time. I resighted it in and went to the match next week. While at the match I found the rifle was shooting high again. To make a long story short this trend keeps continueing through 3 scope and two scope mount changes along with trying to relieve any binding in the bedding and checking screw torque. This problem is totally unacceptable for silhouette shooting for which this particular model is marketed for.
Upon writing your company I received a reply from your gunsmith that said I needed to pillar bed my gun to make it shoot. I wrote back stating my opinion that I felt that I did not believe a consumer should have to go through such drastic measures to maybe make a new rifle work for what it was designed for. We are not talking slightly larger groups or something else anal we are talking about regular point of impact changes measured in inches.
Upon receipt of this second email your company wrote back "Good luck with you shooting" (I have both emails your company sent me along with my emails sent to CZ if needed.)
I feel this was a total brush off of me as a customer with a legitimate problem. Also I had posted this problem on the CZ forum trying to figure out how to fix it under a thread rising POI. Later on in the posts on this thread when nothing seemed to work and I contacted CZ, I posted your companies reply. I feel that the 1600 plus viewers of this thread were shocked that your company with usually a good product and normally good customer service would give me such a non answer as "good luck shooting", and that I the customer was given the brush off. I was not asking for a replacement or wanting my money back I just wanted some help and I felt your companies response was totally inappropriate.
Normally your company makes a great product, as I can attest because I have your centerfire rifles. But every company has a defect or problem occassionally with one of its products. It is how a company resolves the issue when a problem arises that sets it apart. I feel your company really fell down on the job this time.

Sincerely,
John J. Kaufman

[gunnut69]

What's the status of your problem..  With those target knobs I'm still wondering if perhaps somebody got the urge to turn them or perhaps yours turning them accidently during transport..  When you tighten the screws on the action does the action sink into the stock?  Is there motion??

[crazyjjk]

What's the status of your problem..  With those target knobs I'm still wondering if perhaps somebody got the urge to turn them or perhaps yours turning them accidently during transport..  When you tighten the screws on the action does the action sink into the stock?  Is there motion??

Right now I am kind of in a holding mode. Started the process to take the sear and trigger out of the rifle since to correctly pillar a CZ 452 you need to file down the receiver flat where the screw just in front of the trigger is. Upon removing the sear I found that the hole for the spring and ball in the front portion of the sear was drilled way off center.  Also found out that because the hole was off center they did not drill hole as deep as other CZ sears (Checked against another 452 and mine was 0.125" less dept). (Could never get my trigger right even with a Brookie kit). I believe they did this because the hole was so off centered they were afraid they were going to punch through the side of the sear if they drilled any deeper. Seeing this I became even more frustrated with this rifle, and stopped there. So disgusted I went to put the sear/trigger assembly back together just so I would not lose the parts. (Don't like working on things when I am upset as I tend to not have my mind on what I am doing and screw things up.) Found that with the hole in the sear cut so short I could not get the spring and ball to compress far enough to get the sear back in it would just keep binding. So I took it to my local gunsmith to see if he could help. He could not get it in either. He did have a automated solutions adj sear for a CZ there which we put it in so everything was together for the time being. Made a world of difference in the trigger.  I have calmed back down now so when I have some time I will go back in file down the receiver flat and pillar bed the gun. I have a CZ 550 rifle that works flawlessly but with this 452 I a beginning to become afraid to do anything else with it because I am afraid of what I will find next when I take it apart.

As for the target knobs it would not matter if someone turned them because for silhouette I have my elevation numbers marked down for each bank of targets and always turn the knob to those numbers before I shoot.

[gunnut69]

It bothers me that the elevation is all thats changing and it only changes after the rifle sits in the valut for a while.  If the stock were collapsing the impact should move in various directions.  Movement is always the same way, up, and it's not after the shooting session it's after the rifle has rested!!  How close are you to runnig out of adjustment on the scope??  After eight inches plus whatever you're over you should be getting close.  Is there any correlation between the amount of movement and the rounds fired or the amount of time the rifle sits in the vault? As an asside the way to avoid filing that receiver is to file the pillar into a 'V; shape.  The round receiver will center in the 'V' the same each time and be as solid as can be.  Remember the pillar is just a spacer whose job is to seperate the bottom metal and the receiver exactly the same each time the rifle is assembled and to stop compression. I dispense with the pillars altogether and instead pour the pillars from aluminum reinforced Acraglass.. The pillar fits the exact contour of the receiver and the bottom metal and will never compress.  It's a more exact method than cutting tubing to length and trying to match receiver contours.

[crazyjjk]

Well I guess I have to eat crow. Anybody here know a good way to make it?

I received a personal phone call from Alice Poluchova, President of CZ-USA. Said she received my letter and was sorry for the mix up in customer service. I told her I just wanted a little help in getting my rifle straightened out. I was astounded by her reply: She said have the rifle be ready to be shipped in three days. They would have the rifle picked up by UPS and as soon as they received it they would ship me a new rifle..
I was astounded. Talk about service! Remington and a few other firearms manufacturers need  to take lessons. Made a lifelong  CZ fan out of me. Guess I will have to go put that CZ-550 in 9.3x64 on lay away.>John