I bought a prechambered .270 barrel, it's a Stainless steel Kimber fluted 24" in .270 win, I want to use it on a DWM 1908 action I have. I made the measurements and it looked like it would be short chambered a few thousandths. I don't have a .270 reamer, so I put the barrel on, it closes on a factory cartridge with a slight resistance to the bolt. Should I go ahead, and use it like that? Should I get a reamer? Or I was thinking just lap the lugs a little.

If the bolt closes on a factory cartridge with a definite feel then the headspace is tight but safe. Be aware though that overall chamber length will also be a little short so you will have to take that into account when trimming. You may rent a reamer from reamerrentals.com and finish reaming by hand. I believe they also rent gauges. Regards, Bill.

Make sure you set that barrel up tight, if you are checking things loose, you will lose two to three thou when the barrel is torqued. Depending on what the gun is intended for, you may be OK with a snug chamber. But, if it is a "far to the outback" hunting rifle, where any and all cartridges must chamber, including the ones your guide has had ratteling around in the truck for 5 years, then snug won't work. It is very easy to measure everything with a depth mike and determine just what the headspace will be before the barrel is put in the receiver, but it really needs a good picture to explain.

Did you tighten the barrel to its final torque position? with a barrel & action wrench & mark that position? you really need to use a set of headspace gauges to know exactly where you are & not have to guess at it. Mauser 98 threads are 12TPI.One thead take up is .0833, divide that into 360 degrees. Thats about .002 every 10 degrees you tighten on the action wrench.

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NRA Life member

Rather than buying rent the reamer and headspace gauges for a fraction of the price and be on the safe side. You can rent everything you need at www.reamerrentals.com