A good friend and I are trying to figure out what is going on with his rifle. As it says in the subject line it is a CZ 455 Varmint in .22LR with a 5 round magazine.

This rifle shoots great for the most part. 4 rounds inside 1" at a measured 100 yards off a rest is virtually a sure thing. Now the problem.

The first round out of every magazine fired is anywhere from 2" - 3" to the right of the next four. It is always the first round fired, cold barrel, hot barrel, no difference. Also, if we just load 4 rounds the same event happens but with 3 in a nice cluster and the 1st round fire out to the right.

It does it with all brands of ammo we have tried. Bedding seems fine, crown is clean and crisp. Screws are tight.

Anyone ever seen or heard of this before? Any ideas?

I am posting this in Rimfire Rifles & Pistols as well.

Try shooting the gun single shot and see if the problem persists. If it goes away and then comes back when you use the magazine then it's probably pressure from the loaded magazine and the bunched up mag spring raising or changing the position of the bolt.

This problem is common in the 581 - 582 Remington series when they are built into target guns. The cure in those guns is to remove all the bolt nose clearance and create some crush pressure so the bolt is forced to the same position every time.

Never heard of that problem in the CZ. I have owned a few and it's never cropped up.

this topic was on rimfire central and seemed fairly common not sure I remember correctly but seems it was burr in chamber where it met the lands and grooves it was a long article and nteresting,its in the cz section under sophia's questions and answers under cleaning topic is cold barrel flyers.

quote:

Originally posted by Mike Ray:
this topic was on rimfire central and seemed fairly common not sure I remember correctly but seems it was burr in chamber where it met the lands and grooves it was a long article and nteresting,its in the cz section under sophia's questions and answers under cleaning topic is cold barrel flyers.

Found the topic. Seems they have a tight throat and a lead ring can build up. First shot is off but clears the ring. next ones build it up again. Interesting concept. have to see if that is the answer.

Thanks,

how would that always make the first shot a flyer?

quote:

Originally posted by ramrod340:
how would that always make the first shot a flyer?

Beats me. I can't wrap my head around the whole issue.

If you only put 3 in the magazine is the first still a flyer? Or does the mag need to be full? If it has to be full then like SC said maybe it is putting pressure upwards on the bolt.

Their thought is there is a sliver of lead at the end of chamber that has cooled and is harder than the shots fired after as they have heated it up thus being softer and less grab. I just don't know but some of the posters claim they sent gun back to CZ and was fixed. Just sounds to complicated to think about .

quote:

Originally posted by Mike Ray:
Their thought is there is a sliver of lead at the end of chamber that has cooled and is harder than the shots fired after as they have heated it up thus being softer and less grab. I just don't know but some of the posters claim they sent gun back to CZ and was fixed. Just sounds to complicated to think about .

I just don't know how to reply or respond to that. I think I'll just put on my tinfoil hat, mount my purple unicorn and ride off over the rainbow.

Check all the stock screws and scope mount screws.

If a "ring of lead in the throat" is the issue, then the problem should not appear with FMJs or other bullets that have a closed base (no lead exposed.

Give that a try.

George

Try switching the first and last round in your mag.

I don't know if you can still, or ever could get FMJ 22RF ammo GeorgeS. There was a run of it made in South Africa for some of the spook-buzz-saws to be quasi legal for military use. But I think they gave pressure problems in regular 22s and were never released to the public.

quote:

Originally posted by ramrod340:
If you only put 3 in the magazine is the first still a flyer? Or does the mag need to be full? If it has to be full then like SC said maybe it is putting pressure upwards on the bolt.

It does it with 4 in the mag but haven't tried 3.

TEST 1. My advice would be to see what happens when you load it from a magazine that has ONLY one round in it.

TEST 2. Load a full magazine, fire one shot. Don't cycle bolt.

Drop the magazine, replace the fired round, cycle bolt fire one shot. Repeat three more times and see if they all group the same.

It may be this pressure on the bolt thing or it may be that somehow that first round is getting damaged as it feeds in.

TEST 3. Have you tried ejecting that first round without firing it to see if it is damaged?

I don't suppose you have ever tried shooting it single shot? Without the mag?

Hopefully I can get back at it this weekend.

How have you been cleaning it? Tried scrubbing the chamber and leade down to bare clean steel yet?

As it seems to have turned out, the folks saying it was lead build-up in the throat were apparently correct. Got it all scrubbed out and 5/5 in a MOA from the rest. Several brands and several times. Seems that unlike many other .22 rifles, this one needs the throat de-leaded (made that word up) after about 50-70 rounds.

Now it is known and all is well.

While I have no doubt lead in the throat would be an issue. I'm still confused as to why it only makes the first round a flyer.

But glad it worked out for you

I am totally clueless but I'll take it. Magic is all I can think of. LOL