I just got a Mosin Nagant from CanadaAmmo the other day. I wasn't sure if they check head space before the sell/ship them, so decided to check around online for head space gauges.
I found that a lot people are using "Okie Gauges", but at a cost of over $50 + exchange + shipping from US, a set would end up costing almost $100.
I did the next best thing and went "bubba" for 30 minutes.
I hauled out the "stuff" can and started checking washers for thickness. Info from Forster's website says the "no-go" is 0.071", "Field" is 0.074". I found a washer that was 0.077" thick. It was quite a bit larger in diameter than 7.62x54 cartridge case, so I ran the washer onto a bolt, locked it in place with another bolt, chucked it up in the drill, and went to town with a file.
20 minutes (and 1 dead drill battery) later, I had it filed down to 0.645" diameter which is 0.015" smaller than cartridge head diameter. I then put the washer into my vice and started filing 1 edge down enough to clear the extractor. 5 minutes later, the washer sits nicely on the bolt face.
Next came the task of making the washer thinner. Out came my sheet of glass and some 240-grit sandpaper. I initially just took the burr off the edges of the washer and checked for thickness. 0.076"..............off to town with the sandpaper. A few minutes later I had it down to 0.074", so checked the head space. Wouldn't close on my homemade "Field" gauge. PERFECT!
A few more minutes sanding had it down to 0.072" thick. Checked again, bolt won't close. Good to go!
I left it at 0.072" thick, wiped some "Corrosion-X" on it and put it away.
At least now I'll feel safer taking the first shot with my new rifle.
Hope this post helps out and encourages somebody else to think outside the box.
I found that a lot people are using "Okie Gauges", but at a cost of over $50 + exchange + shipping from US, a set would end up costing almost $100.
I did the next best thing and went "bubba" for 30 minutes.
I hauled out the "stuff" can and started checking washers for thickness. Info from Forster's website says the "no-go" is 0.071", "Field" is 0.074". I found a washer that was 0.077" thick. It was quite a bit larger in diameter than 7.62x54 cartridge case, so I ran the washer onto a bolt, locked it in place with another bolt, chucked it up in the drill, and went to town with a file.
20 minutes (and 1 dead drill battery) later, I had it filed down to 0.645" diameter which is 0.015" smaller than cartridge head diameter. I then put the washer into my vice and started filing 1 edge down enough to clear the extractor. 5 minutes later, the washer sits nicely on the bolt face.
Next came the task of making the washer thinner. Out came my sheet of glass and some 240-grit sandpaper. I initially just took the burr off the edges of the washer and checked for thickness. 0.076"..............off to town with the sandpaper. A few minutes later I had it down to 0.074", so checked the head space. Wouldn't close on my homemade "Field" gauge. PERFECT!
A few more minutes sanding had it down to 0.072" thick. Checked again, bolt won't close. Good to go!
I left it at 0.072" thick, wiped some "Corrosion-X" on it and put it away.
At least now I'll feel safer taking the first shot with my new rifle.
Hope this post helps out and encourages somebody else to think outside the box.
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