Wow this form is amazing? thank you for the tip on how to remove the bolt guide. I have been looking for the Eley sub sonic HP but would like to try SK. I will clean the chamber, I have some JB bore cleaner - I'll do that, maybe thats the issue?
CZ 455 Accuracy - Not what I expected
- Thread starter shellbird01
- Start date
Accuracy is predicated on good ammo. Except for the Eley ammo, and perhaps the CCI Standard Velocity, the ammo listed are not suitable when striving to put two bullets in the same hole or even close to one another. Expect poor results from bulk ammo and especially from any that says "Remington Subsonic." Give that stuff away -- but not to a friend. It is necessary to use entry level match ammo, such as the Eley or something like SK Standard Plus, which is widely reported to be good in CZ rimfire rifles.
You don't say anything about cleaning between rounds or how many of each were tried. Shooting 5, 10, or 15 of one kind and then switching doesn't tell you very much. Torque the barrel retention screws to 30 inch pounds and the action screws to 20 inch pounds. Leave them there, checking periodically, until you find ammo with which you can consistently shoot at least 1" groups at 50 yards. Those torque levels will serve you well until you find ammo with a fighting chance for success.
You might try shooting at 25 yards to help eliminate the chance of shooter error as it is exaggerated as the distance increases. If you aren't shooting ragged hole groups with Eley or CCI SV at 25 yards then there's a good chance there's something amiss with the rifle, the scope, or (perish the thought) the shooter/set up.
Good feedback from others in regards to the ammo you have tried. I would give SK Standard Plus a serious consideration. If you haven't cleaned your barrel since you got the rifle, except for using a bore snake, there is a good chance there are lead deposits inside of the barrel. Get yourselves a bore guide and scrub the barrel gently with a bronze brush.
You haven't mentioned if your Leupold has adjustable objective or if it is the non AO version.
K
You haven't mentioned if your Leupold has adjustable objective or if it is the non AO version.
K
Just going off your statement that it seemed to shoot better when you first got the rifle, at this point fouling is certainly a contributing factor that needs to be addressed. Will it totally cure the rifle? I don't know but it'll be checked off the troubleshooting list. At the very least it should restore the accuracy to what you were initially seeing. It's not always easy to figure these things out especially if multiple issues are in play. Seeing your group patterns will help give a clue as to what to look at.
I'll show ya some chamber crap I had once after shooting only 100 Remington Thunderbolts, pictured after two scrub sessions with a bronze brush and soaking overnight in solvent. Big lead speed bump in the chamber, just ahead of the case mouth. Stuff like that is gunna put pressure on a chambered round and tilt it out of alignment with the bore hurting accuracy. Soft lead grows and mutates with every shot so the next round gets a different amount of pressure and tilt put on it, no consistency. Bye Bye accuracy, the JB bore paste was needed to remove it. Better ammo has never fouled up my rifles like that Thunderbolt did.
More remnants of the carbon ring before it got the paste. 100 rounds, I can only Imagine the 2K buildup!
Ammo wise if CCI std. is the "best" readily available to you shoot it some more. 1/2" - 1" groups with it at 50 yards are reasonable in a proper rifle. Groups above 1" indicate an issue persists.
I will get some SK for sure. I have already purchased the nylon bore guide from Nordic, just got to get the Male to male for the dewy rod to the brush (I'm getting there). The scope has a Adjustable objective. Thank you.
Like most others have said, it's most likely an ammo issue. Both my Cz, s 452 and 455 varmint preferred SK std plus .Center x worked well in the 455. My 455 was a good one, pillar beded Boyds stock, 8 Oz trigger. Would shoot. 3 to .7 at 50 yds. My 452 was mostly .4- .8 @50 yds 2nd trigger. My Cz, so did not like max torque. I was usually around 20 inch lbs on both screws. Accuracy dropped when going up.I did not find the Cz to foul quick, it liked a dirty barrel. I found cheap ammo like cc I sv, Aguila sv,Remington subs to shoot around 1" @ 50.
There's no substitute for good ammo your rifle likes.
There's no substitute for good ammo your rifle likes.
Just going off your statement that it seemed to shoot better when you first got the rifle, at this point fouling is certainly a contributing factor that needs to be addressed. Will it totally cure the rifle? I don't know but it'll be checked off the troubleshooting list. At the very least it should restore the accuracy to what you were initially seeing. It's not always easy to figure these things out especially if multiple issues are in play. Seeing your group patterns will help give a clue as to what to look at.
I'll show ya some chamber crap I had once after shooting only 100 Remington Thunderbolts, pictured after two scrub sessions with a bronze brush and soaking overnight in solvent. Big lead speed bump in the chamber, just ahead of the case mouth. Stuff like that is gunna put pressure on a chambered round and tilt it out of alignment with the bore hurting accuracy. Soft lead grows and mutates with every shot so the next round gets a different amount of pressure and tilt put on it, no consistency. Bye Bye accuracy, the JB bore paste was needed to remove it. Better ammo has never fouled up my rifles like that Thunderbolt did.
More remnants of the carbon ring before it got the paste. 100 rounds, I can only Imagine the 2K buildup!
Ammo wise if CCI std. is the "best" readily available to you shoot it some more. 1/2" - 1" groups with it at 50 yards are reasonable in a proper rifle. Groups above 1" indicate an issue persists.
I tired to upload the Groups but photo bucket had an issue with a Mac Computer. Those are some awesome pictures, maybe I could go by my local gun store to see if they have a borescope, you wouldn't know if you didn't see it. Very cool. Also, CCI Std velocity used to give me 4 ragged holes & 1 dang 1-2" flyer. I've since sorted by weight, but can't really tell the difference as most everything is shooting poor. I think your right about the cleaning. There's hope!
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If you don't want to wait for SK std to come in try a few different boxes of SK ammo that Hirsch has in stock ,like polar biathlon, pistol match ,biathlon sport. 2 boxes each and I'm sure you will see an improvement, especially after a good cleaning as rabid suggest, s
Sorry I posted that question before I saw your comments, so 2 boxes & a good scrubbing should be enough for testing. Cool thank-you.
10-5 shot groups (1 box) of an ammo will show you if it has potential or not, don't think too much about the first few groups they will usually have some fliers as the lube on the ammo spreads into the bore until there is an even coat inside. If the ammo is a great pairing the first groups will still be good, and then get better! If changing to a different brand first run a couple dry patches through the barrel to avoid mixing lube types from the different brands. If you get results you like from a certain brand, you'll have enough ammo in the second box to clean the rifle, sight in again and do some hunting while you wait on delivery of a brick (or case
) of that ammo.
After pillar bedding my CZ455 Varmint did not like Eley Match grades, 0.70 at 50 yards being the best. CenterX is far better. Since you have tried Eley Match, Cabela's has Federal Match at $14.99 per box and if you order on line they will ship orders over $99 for free to your nearest store. Federal match is manufactured by Ruag in Germany which is RWS and the federal number is 922 (a or b).
The bore of a CZ is tight and a 20 or 17 caliber rod is recommended. Bronze brushes? No in my 22's. Butch's is recommended by Lilja and only use patches on a jag. You may have developed a lead ring just ahead of the chamber and I work that area with a 243 nylon brush dipped in Butch's or whatever. A nylon brush can be pulled back; a bronze brush will break the bristles if you do the same thing. As to using a pull through only use one to get the bulk of the crud out and a .17 or .20 is enough. Do not use a copper dissolving compound with a bronze brush or a pull through.
Try this site: http://www.rrdvegas.com/rimfire-cleaning.html
The bore of a CZ is tight and a 20 or 17 caliber rod is recommended. Bronze brushes? No in my 22's. Butch's is recommended by Lilja and only use patches on a jag. You may have developed a lead ring just ahead of the chamber and I work that area with a 243 nylon brush dipped in Butch's or whatever. A nylon brush can be pulled back; a bronze brush will break the bristles if you do the same thing. As to using a pull through only use one to get the bulk of the crud out and a .17 or .20 is enough. Do not use a copper dissolving compound with a bronze brush or a pull through.
Try this site: http://www.rrdvegas.com/rimfire-cleaning.html
thenerdboy
Regular
- Location
- NB, Canada
Just FYI:
Dan Lilja, Lilja Precision Rifle Barrels
“I think frequent cleaning with bronze brushes is OK. In my experience you’ll get more barrel life cleaning frequently than if you go long intervals between cleanings.”
http://www.accurateshooter.com/technical-articles/barrel-cleaning-debate/
You can read his full comments in the article cited above but TLDR: barrel manufacturers approve bronze brushes but many competitive shooters prefer to avoid bronze brushes and use bore paste instead.
Dan Lilja, Lilja Precision Rifle Barrels
“I think frequent cleaning with bronze brushes is OK. In my experience you’ll get more barrel life cleaning frequently than if you go long intervals between cleanings.”
http://www.accurateshooter.com/technical-articles/barrel-cleaning-debate/
You can read his full comments in the article cited above but TLDR: barrel manufacturers approve bronze brushes but many competitive shooters prefer to avoid bronze brushes and use bore paste instead.
Thanks guys, I was struggling with which cleaning routine to use. My initial thought was not to do any damage and use bore snake until I knew what I was doing. Thats great.
This might be a dumb question(s):
1. I have a Dewy .22 coated rod but it sounds like I should be using a .20 or .17 but what do you use if you change the barrel to .17?
1. With the.20 or .17 rod your still using a .22 brush correct?
2. Those bronze jags with all the spikes sticking out look dangerous to me, is there a certain style of Jag I should be using and it's also .22?
Thanks
This might be a dumb question(s):
1. I have a Dewy .22 coated rod but it sounds like I should be using a .20 or .17 but what do you use if you change the barrel to .17?
1. With the.20 or .17 rod your still using a .22 brush correct?
2. Those bronze jags with all the spikes sticking out look dangerous to me, is there a certain style of Jag I should be using and it's also .22?
Thanks
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Give it to me then. I'll take all the Remington Subsonic you have. Last time I saw it for sale in Saskatoon it was about $65 a brick. No, it is not real target ammo like Lapua Midas + or the like, but it shoots in the 1/2" range at 50 yards. Here is a target of 4 groups of 4 shots at 50 yards that averaged 0.554" center to center. The bottom left group is close to 1/4". However like all cheaper ammo it has flyers that catch up to it. It makes good gopher ammo, but it has become too expensive and hard to get.
My standard way of testing is with one box of 50. I use two shots as foulers, and then shoot 24 groups of two. I measure them all, and calculate average group size and standard deviation. The sample size of 24 gives you a statistically significant group to make a determination from. I also shoot indoors at 40 yards to take the wind out of the mix. Those test results I think I posted for you earlier were all done that way. If I am shooting a number of boxes, I do not clean between boxes. I recall I have tested as many as 10 ammo types in one shooting. I don't believe in all the fancy cleaning methods. I pull a bore snake through twice with solvent in the brush area, and on the second pull I put a bit of gun oil on the tail too. After a cleaning I will shoot a few more fouler shots to get rid of any oil, and establish some powder residue in the bore.
I use a plastic 22 cal jag, with a Tipton CF rod.
I have never had an issue using a bronze brush, I just always clean it with brake cleaner and blow it dry with compressed air.
It's not going to hurt a cold hammer forged barrel. Just be careful of the crown.
