Bolt a bit hard to work

C

chris in va

New member
My new CZ carbine in 5.56 is fantastic and I've fired about 400 rounds so far. It extracts and ejects fine, but using the bolt handle is a bit difficult with the 4x scope bell, and sometimes I have to push the bolt itself for it to feed from the mag.

Should I be using grease instead of oil on the bolt?
 
There should be grease on the moving parts, not oil. Not much of it either.
"...bolt handle is a bit difficult with the 4x scope bell..." That indicates the rings are too low. Has nothing to do with the magnification. Any finish scratches?
 
If the bolt handle is not hitting the bell, try using your palm, not your fingers to operate the bolt handle. Also much faster.
 
I have several scopes that nearly contact the bolt handle as it's operated. So close that the scope covers have to be removed for the handle to clear. Never really had any problems with how well the bolt worked but I'm using my open palm to do so.
 
I would also suggest rings that are higher. With use, the bolt will be easier to operate. Please run a dry Q-Tip around the inside of the receiver where the bolt goes and see if there are any threads torn off. This would indicate a burr on the receiver. Are there any unusual scratch marks on the receiver?
 
No weird scratches that I can see.

I messed around with my die settings and no matter how deep I pushed the shoulder back, I still couldn't get the bolt to close smoothly without some binding. It closes just fine without a round.

I'll have to source a factory round and see if my dies are getting worn out. Starting to wonder if the chamber is cut short. My x39 527 practically feeds itself.
 
Place a cartridge in it, close the bolt, then extract it. Take a look at the bullet, where its widest at, and see if you can tell if it is hitting the rifling.

Match guns are known to bring the rifling back, to where the bullet has to be forced into it, even on small caliber rifles. In other words, they have a short free bore. Though yours is not a match, it makes me wonder if they didn't get the free bore short in it.

If it isn't the above, then it could be that they have the headspace a little tight.
 
The OAL on my 55gr FMJ is 1.220, and I get a rub mark on the bullet ogive 2-3mm above the case mouth. Must be a really tight barrel!
 
Short free bore isn't a bad thing, but it is annoying to have to force the bolt closed. However, that supposed to help with accuracy, since the ogive of the bullet has been pre-started into the rifling. I know of several .22 match rifles that they even do this too, along with larger calibers. That is the theory of it, at least.

Between standard free bore, and short, as in the rifles, there's an in-between length used in pistols, that some say works well in match rifles too.
 
Sometimes if the brass was last used in a different rifle with a bit larger chamber, even after full length sizing, the fit may be tight in a different rifle
that has a tighter chamber. After the brass is fired in the tighter chamber, it will
reshape to the tighter chamber. So if it's chambered in the tight chamber rifle the next time it's a pretty slick fit, even after the brass has been reloaded in the double digits.
Have two rifles of the same caliber both with tight headspace, but one chamber is just a bit tighter than the other. So if I'm loading for the tighter chamber I try to use brass that was last fired in that rifle for a real slick fit even when I'm full length resizing. If you use small base dies it should eliminate that. I chose not to go that route as I really don't find it to be that big of a hassle.
Whether that is your problem or not I can't say. If this is used brass that is new to you that was fired in a different rifle then it might be. If your fired case is rechambered (before its full sized and reloaded) and goes in pretty slick then maybe so. Assuming you are trimming your brass to spec. Idaho Gaiters
 
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I messed around with my die settings and no matter how deep I pushed the shoulder back, I still couldn't get the bolt to close smoothly without some binding. It closes just fine without a round
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Purchase a Hornady LNL headspace gauge (with bushings) and the bullet comparator. Together they'll tell you what your loads really are- as relates to certain aspects of the chamber.

If you have a tight chamber, sometimes a factory die might not provide quite enough shoulder bump, and may need to be ground (Hornady does this if you send them the die). They're conservativelydimensioned so as to prevent any over-sizing that could result in excessive headspace.

With the headspace gauge, it's a simple matter to compare shoulders of new brass, your fireformed brass, and your re-sized brass- to see if you're getting enough shoulder bump. If your die won't give you .002 (.001 minimum) bump from your fireformed brass, the base of the die needs to be ground.
 
First thing is to take a sized case no primer or bullet and chamber it. Also take a fired case before resizing and chamber it. Does the bolt close easy or hard.
Does store ammo give you the same problem or just your reloads?.
 
Resized cases give me some resistance when chambering, not nearly the effort of a freshly fired.

Really I'm having more of an issue pushing the bolt forward with the handle, even using the heel of my hand. I usually have to push the back of the bolt to get it started. It's almost like the mag spring is way too stiff, which is weird as my x39 mag spring isn't nearly as strong.
 
Take a close look at the extractor. It may not have enough bevel to ride over the rim easily, or maybe the spring tension is too strong. Better yet, take it off and try chambering a round.
 
Chris- You say resized cases give you some resistance?.How about ( if you can) Take a store round get the bullet out of it ( Kenetic Hammer) and Chamber that one. If it goes with no resistance ( as it should). You might be in line for a small base sizing die. I have had to get 2 of them already for stock rifles. Sometimes you just have a tight chamber, which is a good thing.
 
Thank you, I'll get a factory round soon as I get a chance to visit the range.

It's entirely possible the die is worn out. Thousands resized.
 
I would very much doubt your die is wore out. Not sure if you can, but does the bolt close hard all the way or just the last little bit. Can you hold bolt back and push a sized brass into chamber with your finger?.
 
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