Home Forums Hunting & Shooting Gunsmithing Tips on checking headspace on 7600?

I came across a used 243 barrel and action assembly with bolt and have installed it on my 7600 that previously was a 30-06. Are there any tips to checking headspace on a Remington 7600? Chambering a cartridge requires a forceful forward pump on my 30-06, and it takes a good pump to chamber an empty virgin 243 brass in the 'new' barrel. I wasn't sure how to use a no go gauge without potentially forcing a fit or causing some damage. It looks like taking the ejector out is a decent headache so I'd prefer to avoid that if possible. Thanks in advance for any tips.

Make sure the chamber is clean and check for a carbon ring. Also make sure the case is trimmed back far enough or the case is sized enough, it doesn't happen enough to find a new case that is oversized, but your chamber could be undersized.


Use the gauge with the bolt and barrel. Mark the bolt where it's in full battery without the gauge and then see where it's at with the gauge. The action bar lock will no engage the action bar until the bolt is in full battery and action bar is far forward enough...mark where the action bar sits too along with the bolt. You can take out the ejector but the extractor is riveted in.

If I’m reading right, both barrels take a good snap forward to chamber brass. If so I would think both chambers are on the minimum side in that rifle. Using a no go gauge won’t show you much if that is the case.

Thanks for the tips so far. The chamber has been cleaned and I don't see a carbon ring. I can check the virgin case for length.

I have the dust cover off so I can see if the bolt is rotating and then fully in battery. I just can't close it the last bit without some oomph with the virgin case. I'll try it a bit more tonight.

Best to check a carbon ring with a case split neck. Dremmel a sized neck in half and seat a bullet, then with the upper half of the neck ring high near the ogive. CAREFULLY chamber and see if it get pushed back lower than chamber length. I went on SAMMI site to find out OAL of the chamber. If the upper half drops lower than you have a carbon ring.


Did you cam over a sized case to see if that chambers?

Best to use headspace gauges rather than cartridges or empty cases.

Always best to use a headspace gauge and do the job correctly. That involves removing the barrel and bolt from the action and removing the ejector. The extractor can be carefully worked around but the ejector must go to have any type of feel. The stripped bolt is inserted by hand in the barrel extension and “closed” on the gage. At least the 7600 is easier to work with than the old 760!

There used to be special head space gauges that had a very small diameter head for using on guns with plunger type ejectors. You most likely will have to remove the headspace gauge with a cleaning rod, but don't have to worry about a flase reading from the ejector plunger.

Just to confirm, I should remove the bolt from the action bar assembly, disassemble the bolt to remove the ejector, and then slide the bolt and the headspace gauge into the chamber and see it the bolt rotates closed manually?

Any tips on disassembling the bolt?

bolt disassembly is very easy. No tips needed. Assemble rifle action enough to test HS. No need to ask a bunch of questions, it's a simple design....if you feel apprehensive about doing it, find someone near you who works on their own guns or find a gunsmith.

I'm fairly handy but getting the pins out has failed so far for me. Does the firing pin need to be removed to drive the pin out and remove the extractor?

No the firing pin doesn’t need to be removed if you just look at it. A rivot holds the extractor not a pin you drive out, l mentioned before. It has to be ground off one side or drilled, better if drilled. Getting it out is one thing but putting it back in is another. Leaving the extractor alone would be best, but will get in the way of properly headspacing.

[quote=qotsarock]I'm fairly handy but getting the pins out has failed so far for me. Does the firing pin need to be removed to drive the pin out and remove the extractor?[/quote

i would leave the extractor alone

Sorry, fellas, I meant to say "ejector" instead of "extractor" above. I am not planning on removing the extractor, but was hoping to get the ejector removed to better check the headspace.

Thanks to input from folks here and Redneck via PM, I was able to check the headspace with the ejector (and extractor) still in place with both a go and no-go gauge. Headspace looks to be in spec.