Bolt sticks on extraction - could it be carbon build-up?

[b6graham]

size your brass...

what can look like pressure with clickers/sticky bolt can easily be brass that isn't getting FL sized enough (see non-OCD alpha brass for tons of examples)

 

[marksman1941]

If your powder charges are in line then it's gotta be case length or the shoulder not being put in the right spot. I have never seen or heard of carbon buildup causing this. I'd be looking elsewhere for the problem.

 

[hawlejr]

If your only neck sizing you still have to full length size them every now and then or they will stick...

Thanks for your input. I was hoping that it would be carbon sintering almost gluing the case in the chamber. So far, nobody is sympathetic to that explanation! I suspect you're right, and the case must have grown in shoulder lenght or body diameter a bit, and so FL sizing should cure it. .......but that just means a lot of time lubing and cleaning which I'm trying to avoid. The other trick I've heard is using the collet sizer twice. After you size it the first time and knock the primer out, spin the case 90 degrees and size it again. This helps if the neck is slightly out of round, or springs back a bit after the first squeeze. This is more likely as the number of reloads per case increases and there is some hardening of the brass. That, trick, however, is aimed more at helping the cartridge chamber more easily. You would think that after it chambered successfully that it would extract without issue....except in my situation.

 

[hawlejr]

If these are stiff to lock down the bolt that sounds like the shoulders are up against the chamber

Yes a little, but not enough to worry about. The extraction is where there is a problem. It's a lot tougher to turn the bolt up to open, and really really hard to pull the bolt back to extract and eject. I'm trying to avoid FL sizing, but I'm afraid I may have to do that.

 

[b6graham]

neck sizing is dumb in the first place. just FL size and poof magic...problems gone forever

 

[hawlejr]

If your powder charges are in line then it's gotta be case length or the shoulder not being put in the right spot. I have never seen or heard of carbon buildup causing this. I'd be looking elsewhere for the problem.

So far everybody agrees with you. I was hoping that I could buy a tumbler throw a few hundred cases in there and motor on without FL sizing, but ....looks like I gotta get out the lube and all the mess. Thanks for your input. I do appreciate it, and I'm now pretty **** sure you're right on.

 

[marksman1941]

Take your calipers and measure the case against the factory car dimensions and see if anything is out of spec. Specifically in the OAL and the shoulder location

 

[victor3ranger]

If it was me I would still get a tumbler

 

[Koda_]

Thanks for your input. I was hoping that it would be carbon sintering almost gluing the case in the chamber. So far, nobody is sympathetic to that explanation! I suspect you're right, and the case must have grown in shoulder lenght or body diameter a bit, and so FL sizing should cure it. .......but that just means a lot of time lubing and cleaning which I'm trying to avoid. The other trick I've heard is using the collet sizer twice. After you size it the first time and knock the primer out, spin the case 90 degrees and size it again. This helps if the neck is slightly out of round, or springs back a bit after the first squeeze. This is more likely as the number of reloads per case increases and there is some hardening of the brass. That, trick, however, is aimed more at helping the cartridge chamber more easily. You would think that after it chambered successfully that it would extract without issue....except in my situation.

it wont be carbon sintering that causes a sticky bolt. A sticky bolt will only be overpressure or a case thats only been neck sized too many times. A carbon ring in the chamber will still feed smoothly because each cycle naturally wears with the size of the case neck. A carbon ring can cause pressure issues (sticky bolt) but that would likely show up with other ammo and your new brass which you said runs fine. All symptoms so far, to my knowledge, point to you not full length sizing your brass every few firings. Thats a well known issue with neck sizing only.

 

[Koda_]

I appreciate all the inputs guys, and I normally would spend a lot more time on the brass if I was doing serious load development or going on a hunt. In fact I wouldn't use these cases at all. I'm practicing mounting the rifle and shooting quickly. I'm also practicing shooting off sticks. I'm practicing working the bold quickly and firing rapid follow up shots. I'm not trying for super tight groups off the bench. In fact, I'm not using a bench at all. I'm happy with rounds that give me better than 2 MOA.

it doesnt matter what you use ammo for it has to be manufactured correctly. A sticky bolt is a sign of a problem that will eventually fail if you dont correct it.

 

[hawlejr]

it doesnt matter what you use ammo for it has to be manufactured correctly. A sticky bolt is a sign of a problem that will eventually fail if you dont correct it.

Thanks! I need to correct it to do the type of practicing I indend to do for the next few weeks. So it's going to get corrected. Most of the votes so far indicate FL sizing which is what I wanted to avoid, but looks like I'm going to get stuck with. Thanks again.

 

[hawlejr]

If your powder charges are in line then it's gotta be case length or the shoulder not being put in the right spot. I have never seen or heard of carbon buildup causing this. I'd be looking elsewhere for the problem.

Thanks that's what I needed to hear!

 

[Koda_]

Thanks! I need to correct it to do the type of practicing I indend to do for the next few weeks. So it's going to get corrected. Most of the votes so far indicate FL sizing which is what I wanted to avoid, but looks like I'm going to get stuck with. Thanks again.

since you practice a lot you'll get more case life if you anneal and FL size.

 

[26Reload]

Be interested to see pictures of the throat of the chamber....let's see what the carbon build up looks like....if you nylon brush is even removing anything....