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Posted: 1/29/2006 7:54:50 AM EDT
I just trimmed the ejector tab? so the bolt would pass but I ran into this problem. The bolt carrier will go all the way without the bolt. When I put the bolt in it looks like this and doesn't close all the way. Any suggestions?
 
Link Posted: 1/29/2006 8:08:47 AM EDT
[#1]
This is a very common but hard to diagnose problem.  It seems to come up at least once per week.  I have had it a few times myself.  Here is what I would check, based on my experience.

Check to see if the bolt will rotate into locked position when held by hand (that is, without the carrier).  If it wont, then the barrel is in too far.  You should have about 7 thousands gap between the bolt and the chamber.  If the bolt locks up freely by itself, then you probably have misalignment somewhere that is causing binding.  You can check alignment by taking off the gas tube and putting everything back together again (without the gas tube).  Check the alignment of the piston with the gas port.  Any misalignment will be magnified there.  You should be able to easily guide the piston into the port with your finger tips.  What you have to do depends on what you find.

Also check is for crud in the gas port.  Crud has been known to keep the carrier from going fully forward.

Link Posted: 1/29/2006 8:27:47 AM EDT
[#2]
Ok, I took the gas tube off and the piston seats fine. It looks like the bolt is not rotating right at the end when it's next to the barrel. Is it possible the barrel is in too far? I can manually run the bolt through but it is hard to turn it in to position by hand.
Link Posted: 1/29/2006 8:49:06 AM EDT
[#3]
when you reinstalled the barrel did you use headspace gauges? on my first Romy build I did not have them, I marked the barrel where it seated against the trunnion, then took several measurements inside for barrel location. I got lucky with that one, but never want to take a chance like that again. headspace gauges are inexpensive and easy to use, when your done sell em'.
Link Posted: 1/29/2006 9:00:10 AM EDT
[#4]
I would double  check your ejector length
Link Posted: 1/29/2006 9:19:33 AM EDT
[#5]
Yeah I will have to learn from not making barrel marks. I don't have headspace gauges and the ejector has been trimmed. The bolt passes the ejector easily.
Link Posted: 1/29/2006 11:39:33 AM EDT
[#6]
Sounds like the bolt is hitting on the end of the barrel.  Check for damage on the end of the barrel.  You may have bunged up the end of the barrel when taking it out.  Or, the barrel might be in just a little too far.  Believe it or not, it is possible to get the pin in with the barrel in too far.  If this is the case, you have too LITTLE headspace, or more accurately, not enough bolt gap.  Here is a thread where I discuss what bolt gap is, how to measure it and how it relates to headspace.  There are even pictures. Bolt gap thread

If you decide that the problem is bolt gap, see if you can push the action fully closed by hand (no hammer please).  If you can, I suggest taking it out and shooting it as a single shot.  The barrel may shift back into the correct position which is forward against the pin.  It may take a few shots before things loosen up.  

Someone will probably come along and tell you that this is not safe.  I dont see any problem with it and have done it myself.  The force from a fired cartridge is enough to over come the friction between the barrel and trunnion (to move the barrel forward until stopped by the pin), but not enough to shear the pin.  Headspace guages would be a good idea since that is what you are playing with if you do this.  But the most important thing is bolt gap, as I discussed in the linked thread.  You will have to decide for yourself what is safe and what you are comfortable doing.
Link Posted: 1/29/2006 2:28:33 PM EDT
[#7]
Your bolt is hitting the trunnion when closing.  Remove the bolt, and re-insert the bolt carrier.  Check for fit.  If everything seems to be working fine, replace the bolt and check where the bolt first passes the trunnion and also the ejector.  Chances are... your hang up is one of these two places.  

Make sure that your lower rails are level (parallel) with the top rails, and are dead -on even with the trunnion ledge.

HTH

Mack
Link Posted: 1/29/2006 4:12:58 PM EDT
[#8]
I had a very similar problem on my first build..

Headspace checked fine with guages.

It would feed brass cased rounds but not steel cased...

The carrier would close to about 1 inch..like yours.

I noticed that the casings had scrape marks on two sides...about 1/8 inch from the rim of the case.

I took a dremael tool and polished the inside edge of the chamber...did not remove material...just polished it real good.

Still passed with go and no go guages

That cured my problem...feeds both steel and brass cases now.

I am not endorsing that you do this, but it worked for me.

Good luck
Link Posted: 1/29/2006 5:18:21 PM EDT
[#9]
I did a very good cleaning job on the whole thing and pushed the barrel out about a 1/32 and the bolt is perfect. I guess there wasn't enough room for it to turn. I pull the bolt carrier back and let it go and it meets up perfectly. Thanks to everyone who offered suggestions. This was a first build. The result is posted up of down a couple of threads. Now it's time to paint!!
=M=
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