JJ barrel wont work

[grj1131]

I just dusted off my mini-mag (hyper-mag regulator) that has been sitting in my closet for about 10 years, and I did the level 10 tune up with all new internals and spring, as well as putting all new o-rings and seals on regulator. After working with it and getting no leaks I decided to shoot some paint and chrono. Imagine my surprise (and frustration) when I put on my JJ barrel and it wouldn't fire. If i pull the barrel out a bit, then it fires. I had no problems using a smart parts barrel or armson barrel. Any thoughts? Anyone have a similar experience?
P.S. I did try all of the springs and adding shims.

[Cokrkilr]

Try taking the bolt off the valve and dropping it in the barrel. Maybe its a tight bore barrel?

[grj1131]

will try that tomorrow. Thanks.

[BiNumber3]

the lvl 10 bolts can get thicker around the tip (best way to say it, honest) after a while, if it doesn't slide into the barrel easily just get some sand paper

[Cokrkilr]

Mine had the problem described by binumber. I had to sand the bolt a little and the body washer inside my emag body. A lvl7 bolt would fit but not lvl10.

[athomas]

the lvl 10 bolts can get thicker around the tip (best way to say it, honest) after a while...

LOL. They don't get thicker as they sit around. The stainless steel doesn't absorb moisture and swell up.

A small bore barrel can cause problems with a level 10 bolt due to it having a wider tip. The recommended minimum size barrel bore to use with a level 10 bolt is 0.685".

Another potential problem is if the outside of the barrel is slightly smaller diameter. This can cause the barrel to sometimes get pushed off center by the twist lock assembly. If this happens, then the bolt will rub on one side of the barrel and prevent operation. You can correct this one by wrapping some tape around the back of the barrel to artificially make it bigger so that it stays properly centered. Do it in two locations(forward and back) so that you don't get barrel wobble.

[BiNumber3]

didn't mean from sitting think I read somewhere that they start mushrooming from use or something to that effect

[athomas]

didn't mean from sitting think I read somewhere that they start mushrooming from use or something to that effect

The tips don't get hurt. They don't have any impact related issues unless there is a problem with the gun itself. The only place that might have a problem would be the body washer getting mushroomed due to impact. That's not a level 10 bolt issue though. Its a dry firing issue more than anything.

[BiNumber3]

I see, I do know one of my older micros had issues with a lvl 10 bolt, that same bolt worked with every other micro and mag I had though

[athomas]

Yes, some of the older micros had smaller breach bores. I had one like that.

[grj1131]

I checked the bolt and the barrel, and sure enough the bolt only goes about a half inch into the barrel.

[athomas]

You'll have to use a barrel with a larger bore. If you need or want to use a barrel that has a smaller bore, you will have to sand down the ring at the front of the bolt so that it is a smaller diameter.