CZ 455 Integral Suppressed Problems

[canderson]

I have read about bedding and trigger work helping the accuracy problems of the 455. I had an integral suppressed 22LR built. The builder has tried 4 different barrels. The best I can do is 2-3" at 50 yards. I would like suggestions on what to do? Do I gamble on bedding and not being able to return the rifle or just try to get money back? Open to suggestions. Only downfall to getting money back is tax stamp and waiting on a new one. Thanks in advance for any help.

 

[missed]

Play with action screw torque. My 452 was really sensitive to that before I bedded it.

Have you tried different ammo? If your shooting subs and the barrel is not stabilizing them that could be the issue also. I have been kicking around doing an internally suppressed for my 452 but have not yet I just keep the can on the end. My two CZ are shooting Norma TAC very nicely. Will it shoot with a non suppressed barrel on it?

 

[canderson]

I have tried mini-mag, Federal 40r. solid, Remington hollow points, Federal Gold Medal. Tried winchester cheap hollow points and RWS match in one of the previous Barrels. I think the builder Put a "washer" on end of barrel to allow baffles to stack in outer tube. I am wondering if this is now allow the barrel to vibrate consistently. All of the above are sub-sonic. Have shots several ruger integral suppressed, they have no problem with above ammo mentioned. I will play with screw torque.

 

[Hoser]

Is the barrel ported?

 

[canderson]

I think so. I would imagine because the mini-mags are subsonic. (i.e. no crack)

 

[Don Trimmer]

I have read about bedding and trigger work helping the accuracy problems of the 455. I had an integral suppressed 22LR built. The builder has tried 4 different barrels. The best I can do is 2-3" at 50 yards. I would like suggestions on what to do? Do I gamble on bedding and not being able to return the rifle or just try to get money back? Open to suggestions. Only downfall to getting money back is tax stamp and waiting on a new one. Thanks in advance for any help.

I have a CZ 455 Varmint .22 LR. I have only fired supersonic rounds to date. I was also getting poor groups out of the box (2+" at 50 yards). I glass bedded the action and first inch of the barrel, installed a better scope (previous scope was a cheap BSA and I couldn't adjust out the parallax) and rings and started shooting approx. .75" groups at 50 yards. I was shooting Federal "auto match" ammo. NOTE: when shooting a 5 shot group, usually 3 rounds would be about a 3/8" group with 2 "flyers" turning it into a .75" group. I also run a bore snake through the barrel every 20 or so rounds.

I just installed a CZ 11mm to Weaver adapter rail, upgraded the rings again and bought a few rounds of Eley match and a few rounds of subsonic ammo. I'm waiting for the next calm day to pay a visit to the range and see if the ammo and/or better scope mounting gives me another improvement.

My two cents: without a bedding job, the action rests on wood. There is no reinforced post. When torquing the action screws, things seemed a little "squishy". I suspect the wood is compressing and the action and stock are experiencing bending moments. After the bedding job, it felt a lot less "squishy" but still not as solid as metal posts. Maybe I'll get ambitious and add some metal posts one of these days

 

[Sundown]

I have read about bedding and trigger work helping the accuracy problems of the 455. I had an integral suppressed 22LR built. The builder has tried 4 different barrels. The best I can do is 2-3" at 50 yards. I would like suggestions on what to do? Do I gamble on bedding and not being able to return the rifle or just try to get money back? Open to suggestions. Only downfall to getting money back is tax stamp and waiting on a new one. Thanks in advance for any help.

I have a cz 455 that I built a benchrest stock for and did a trigger job on. It diffenately likes the expensive ammo. Measure the diameter of the bullet, a lot of bullets are .223" and you should try the ammo that measures .225" ( eley tenex, federal ultra match, etc.). The best group I got was .227" at 50 yds with federal ultra match which is $21.00 a box.

 

[Jeremy(WI)]

Is the builder the one making the suppressor or is the suppressor just pinned to the barrel? If he has tried 4 different barrels with the same result it could be a bad thread job, not being concentric to the bore. Most of the integrals I have seen online for Rugers have short barrels with a monocore attached. A barrel at 4.5 inch and less will keep most 22lr subsonic

 

[XTR]

Buy different ammo (way cheaper than most other options). My CZ453 won't shoot 3 inches at 50 yards with high velocity stuff but it will shoot ½ inch with SK Jagd Rifle plus or Wolf Target Match.

 

[Dusty Stevens]

Thats what i was wondering is how long is the actual barrel? You may be trying to shoot groups with a 4" barrel and a bunch of stuff after that affecting the gases til it gets out. I dont think the purpose of an integral suppressor is benchrest accuracy

 

[Don Trimmer]

Thats what i was wondering is how long is the actual barrel? You may be trying to shoot groups with a 4" barrel and a bunch of stuff after that affecting the gases til it gets out. I dont think the purpose of an integral suppressor is benchrest accuracy

The CZ455 is a rifle with an approx. 20.5" barrel ... not a pistol

 

[Dusty Stevens]

The CZ455 is a rifle with an approx. 20.5" barrel ... not a pistol

An integral suppressor barrel isnt 20.5" anymore. I know what a 455 is

 

[Don Trimmer]

An integral suppressor barrel isnt 20.5" anymore. I know what a 455 is

Maybe it's my bad. I don't understand references to a 4" barrel on a rifle???

 

[Jeremy(WI)]

Maybe it's my bad. I don't understand references to a 4" barrel on a rifle???

The picture is a Gemtech Mist integral suppressed barrel, the actual rifled part of it might be 6-8 inches but others claim to only have 4.5 or less rifling. The Liberty Pinnacle has 4.75" of rifled barrel and an actual overall length of 16.5 and it should keep most bulk pack ammo subsonic

 

[Don Trimmer]

The picture is a Gemtech Mist integral suppressed barrel, the actual rifled part of it might be 6-8 inches but others claim to only have 4.5 or less rifling. The Liberty Pinnacle has 4.75" of rifled barrel and an actual overall length of 16.5 and it should keep most bulk pack ammo subsonic

OK ... it is my bad! I had no idea suppressed barrels had such short rifling ... I guess that is the whole point so feeling like an idiot

Doesn't this mean the accuracy would be closer to a pistol than a rifle? At a minimum, the baffles have to be blowing all the bullets all over the place ... like a bunch of really bad crown jobs.

 

[Jeremy(WI)]

OK ... it is my bad! I had no idea suppressed barrels had such short rifling ... I guess that is the whole point so feeling like an idiot

Doesn't this mean the accuracy would be closer to a pistol than a rifle? At a minimum, the baffles have to be blowing all the bullets all over the place ... like a bunch of really bad crown jobs.

These are made for the 10/22's and I am not sure what the OP is having made, sounds like a custom job so it could be a 10" barrel with 7' suppressor pinned on. Using a suppressor usually just affects point of impact and actually improved my groups with my Bushmaster in 308. Usually bad groups when suppressed indicates the threads are not concentric with the bore

One review of the Gemtech claimed 10 shot groups that were dime sized at 50 yards

I use a suppressor on my 10/22's but it isn't an integral and I can use it on my 22/45 Lite pistol and it makes a big difference on the noise

It isn't going to win any beauty pageants

The Liberty Regulator has a better look and is supposed to be even more quiet

 

[Don Trimmer]

I've been doing some research ... which is what I should have done before I started typing uninformed garbage. I get that a suppressor can improve accuracy by 1) Reducing the muzzle velocity to the subsonic region so the bullet doesn't have to traverse the problematic trans sonic region as it drops from supersonic to subsonic and/or 2) acting as a barrel tuner and you were lucky enough for it to be an appropriate weight and location so as to make the accuracy better.

What I don't understand:
1) How accuracy can be maintained with such a short rifled barrel
2) It is well known a bad crown job adversely affects accuracy. The baffles in a suppressor appear to be a bunch of horrible crown jobs.

Can anyone point me to a reference that explains WHY suppressors don't seem to adversely affect accuracy?

The Liberty Regulator has a better look and is supposed to be even more quiet

[/QUOTE]


The Liberty Regulator has a better look and is supposed to be even more quiet

[/QUOTE]

These are made for the 10/22's and I am not sure what the OP is having made, sounds like a custom job so it could be a 10" barrel with 7' suppressor pinned on. Using a suppressor usually just affects point of impact and actually improved my groups with my Bushmaster in 308. Usually bad groups when suppressed indicates the threads are not concentric with the bore

One review of the Gemtech claimed 10 shot groups that were dime sized at 50 yards

I use a suppressor on my 10/22's but it isn't an integral and I can use it on my 22/45 Lite pistol and it makes a big difference on the noise

It isn't going to win any beauty pageants

The Liberty Regulator has a better look and is supposed to be even more quiet

 

[Jeremy(WI)]

Suppressors don't reduce velocity, a short barrel on integral suppressor does that as you lose about 50 fps per inch of actual barrell length and the 4.5" barrel on my pistol keeps most ammo subsonic except for CCI Stinger and they are supposed to be over 1600 fps when most of my bulk pack is 1255 fps and the short barrel causes the fps to drop into subsonic range

A bad crown causes the bullet to be affected negatively by the escaping gas, a suppressor by design strips the escaping gas away from the bullet

 

[Don Trimmer]

Thanks Jeremy,

I should have been more specific ... I got that it was the short barrel section that brings the velocity down ... not the suppressor itself.

Re. the baffles affecting the bullet: Once the bullet leaves the barrel, I think the bullet is already separated from the exhaust gasses. The suppressor diffuses the exhaust gasses rather than releasing them to the rest of the world as a sharp explosion. After thinking about it, I agree that a bullet passing through a baffle isn't affected the same way a bad crown job affects a bullet. The bullet does push a shock wave ahead of it, but maybe by the time that shock wave bounces off a baffle and gets back to the bullets path, the bullet is already through the baffle and gone.
Anyway, this is now making a lot more sense to me. Thanks for your help and sorry for hijacking this thread.