Looking for bolt ID help

[fguffey]

I have 35 03A3 bolts; there is not .001" difference in the effect each has on the length of the chamber from the shoulder of the chamber to the bolt face.

F. Guffey

[fguffey]

just need to headspace to make sure and try a few if yours do not work (headspace correctly)

designed that way,

I also have 2 boxes of 2 Brown and Sharp complete bolts. All 4 bolts are identical. If there was a plan to correct the length of the chamber with a bolt logic would dictate the bolts would be different.


F. Guffey

[lyman]

I also have 2 boxes of 2 Brown and Sharp complete bolts. All 4 bolts are identical. If there was a plan to correct the length of the chamber with a bolt logic would dictate the bolts would be different.


F. Guffey

if you gonna quote, quote the entire post, not take things out of perspective,

the 03 (and A3) were headspaced when barreled,
bolts designed to be swapped out, if needed, but not to need any adjustment or fitting, (just check headspace to make sure, due to manufacture tolerances etc)

unlike say in Enfield, that required the bolt head to be fitted,,

I've rebarreled, and worked on many a 1903 and 1903A3, there will be some variation in headspace when bolts are changed , likely due to wear on the receiver and barrel,

[togor]

I have a bolt/action chart that reminds me which bolts headspace how into which actions. Not all 03 bolts headspace the same. Given lots, maybe.

[lyman]

I have a bolt/action chart that reminds me which bolts headspace how into which actions. Not all 03 bolts headspace the same. Given lots, maybe.

would like to see that chart, could you post it?

[togor]

would like to see that chart, could you post it?

It's just for my own motley of bolts & actions! Not a general reference. Just which bolts show what when mated to which actions. I store the bolts in one place and the actions in another since things are a bit of a tight squeeze. So for example the BF9 fails a field gauge in the 1.37M action but won't close on a nogo in the 900K, and the NS bolt fails a go gauge in the 900K, and won't close on a nogo in the 1.37M. The rest of them are right in the middle somewhere, so I agree that random bolt swaps weren't a hazard to the troops. FWIW, both the BF9 and NS bolts were NOS when I got them, not hammered down from heavy usage.

[lyman]

It's just for my own motley of bolts & actions! Not a general reference. Just which bolts show what when mated to which actions. I store the bolts in one place and the actions in another since things are a bit of a tight squeeze. So for example the BF9 fails a field gauge in the 1.37M action but won't close on a nogo in the 900K, and the NS bolt fails a go gauge in the 900K, and won't close on a nogo in the 1.37M. The rest of them are right in the middle somewhere, so I agree that random bolt swaps weren't a hazard to the troops. FWIW, both the BF9 and NS bolts were NOS when I got them, not hammered down from heavy usage.

that variation was not likely from the bolts, but likely from the person reaming the barrel when it was installed,

[togor]

that variation was not likely from the bolts, but likely from the person reaming the barrel when it was installed,

Of course. I've mounted & headspaced barrels myself. The procedure is executed with a specific combination of receiver, barrel, bolt, reamer, and gauges. But obviously the bolts I mentioned in my post above are dimensionally different. If I can do an A/B comparison with the same set of gauges and get an internally consistent result, and the only thing changing is the bolt, then that is where the difference is. A difference of 0.010" is all it takes, and that can be had any number of ways.

[fguffey]

If I can do an A/B comparison with the same set of gauges and get an internally consistent result, and the only thing changing is the bolt, then that is where the difference is. A difference of 0.010" is all it takes, and that can be had any number of ways.

I have one 30/06 chamber that is .016" longer than a minimum length/full length sized case. I form 280 Remington cases to 30/06 cases and add .011" to the length of the case from the datum to the case head to get the magical .002" clearance.

.005" added to .011" is .002" longer than a field reject length gage.

F. Guffey

[fguffey]

if you gonna quote, quote the entire post, not take things out of perspective,

I have always though the saying "you need to purchases a bucket of bolts in case the first one does not fit' was cute. A resource person on military rifles has at least 100 03 bolts, I have 35 03A3 replacement bolts. If I needed a bolt to off set the length of the chamber by .004" I could tell him how to determine which bolt I needed; if he needed a bolt I would have to drove over and check the length of the chamber he was working on.

This stuff is not for everyone.

F. Guffey

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and he has at least 20 30/06 head space gage: all I need is one and I showed him a head space gage is not necessary.

F. Guffey