Here is a trick that works with any rifle/caliber.
For a rimmed or belted case, take a full length sized/deprimed case and place it over a primer. Put something inside the case, like a 3" bolt and tap on the bolt to partially seat the primer. Just get the primer started.
Chamber the case and close the bolt. This will almost seat the primer. Remove the case. Measure the primer protrusion with a vernier caliper. The amount that the primer sticks out is the amount of excess headspace. I like my target rifles to be set to around zero. Commercial rifles are typically in the 3 to 5 thou range.
With a rimless case, I prefer to use a virgin case, but if one is not handy, a full length sized case will do.
I suggest you test several rifles, including a newer, commercial rifle the same way, too, so you can have some comfort that it is normal for the bolt closing to not push the primer completely flush.
Although we all have some concern for headspace on new acquisitions, I have only found excess headspace on one rifle (out of several hundred I checked). It was not a milsurp with a miss-matched bolt. It was a brand new out of the box Winchester 94AE in 356. It had about 8 thou of headspace. They quickly changed a part and made it tight.
A gunsmith I know once commented that he had never found a rifle with excess headspace And then one day he found about 6 of them. All the sniper rifles of a police department had excess headspace. The assumption is that the gunsmith accidently set the headspace with the wrong gauge. At the time my friend did the test, he was getting ready to rebarrel the rifles because each had over 5,000 rounds through it. They shot just fine.
For a rimmed or belted case, take a full length sized/deprimed case and place it over a primer. Put something inside the case, like a 3" bolt and tap on the bolt to partially seat the primer. Just get the primer started.
Chamber the case and close the bolt. This will almost seat the primer. Remove the case. Measure the primer protrusion with a vernier caliper. The amount that the primer sticks out is the amount of excess headspace. I like my target rifles to be set to around zero. Commercial rifles are typically in the 3 to 5 thou range.
With a rimless case, I prefer to use a virgin case, but if one is not handy, a full length sized case will do.
I suggest you test several rifles, including a newer, commercial rifle the same way, too, so you can have some comfort that it is normal for the bolt closing to not push the primer completely flush.
Although we all have some concern for headspace on new acquisitions, I have only found excess headspace on one rifle (out of several hundred I checked). It was not a milsurp with a miss-matched bolt. It was a brand new out of the box Winchester 94AE in 356. It had about 8 thou of headspace. They quickly changed a part and made it tight.
A gunsmith I know once commented that he had never found a rifle with excess headspace And then one day he found about 6 of them. All the sniper rifles of a police department had excess headspace. The assumption is that the gunsmith accidently set the headspace with the wrong gauge. At the time my friend did the test, he was getting ready to rebarrel the rifles because each had over 5,000 rounds through it. They shot just fine.
