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Posted: 1/25/2013 3:41:14 PM EDT
| I am assembling my 300 and I have all new parts. Do I need to check head spacing if so how do I do it? I checked the forum and could not find the info I wanted.Can I upload a picture here to show how the barrel and upper receiver is righ t now? |
| Should there be this much distance http://i1358.photobucket.com/albums/q778/bobwhite282/300_zpsaefa4b3e.jpg" /> |
| No. That barrel extension pin will be fully inserted in it's slot before you install and tighten the barrel nut. BTW - This has nothing to do with headspace which was established by the barrel maker when he cut the chamber. There is some tolerance deviation between bolts, but you are almost positive GTG as far as headspace is concerned. |
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Quoted:
Should there be this much distance http://i1358.photobucket.com/albums/q778/bobwhite282/300_zpsaefa4b3e.jpg" /> No. Grease it up and tap it in. Headspacing is already set by the barrel extension and barrel from the manufacturer - and the bolt face. Also use molybdenum (no graphite) grease on the threads when assembling. Mil Spec is Aeroshell 33MS but a quality moly lube from an autoparts store will do. ETA: The extension is the threaded piece on the end of the barrel with the lugs. It can be checked with a series of "Go" and "No go" gauges and instructions are posted here somewhere. If parts (barrel and bolt) are within spec it typically isn't an issue. Any correction to the barrel and extension would have to be made by the maker. |
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